1 Computational Model for Processing Lexical Information Zoltán Bánréti2 Copyright 2000 Zoltán Bánréti, Katalin Kiss, Gábor Rádai, Péter Rebrus, Péter...
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Contents Abstract ........................................................................................................................................................... 1 Objectives ........................................................................................................................................................ 2 Findings........................................................................................................................................................... 3 List of publications........................................................................................................................................... 4 Detailed dummary of the results of the reserach ................................................................................................ 6 Neurolinguistics submodule.......................................................................................................................... 6 Open and closed class lexical items in the mental lexicon and their role in sentence processing.................. 6 Representational complexity of verb in mental lexicon and its effect on aphasics sentence production........ 8 Ellipsis in sentence processing ................................................................................................................ 10 Syntax-semantics submodule...................................................................................................................... 12 Ellipsis and the structure of the lexicon ................................................................................................... 12 The interpretation of certain logical vocabulary items in adult and child usage......................................... 13 Aspect and Argument Structure .............................................................................................................. 14 Phonology submodule ................................................................................................................................ 15 Degrees of phonotactic grammaticality: partitioning the lexicon .............................................................. 15 Phonotactics and morphological complexity............................................................................................ 17 Computational linguistics submodule.......................................................................................................... 19 Representation of linguistic knowledge ................................................................................................... 19 Extension of the GIN formalism ............................................................................................................. 20 Non-Complin References in Section 10................................................................................................... 22 Closed class lexical items in sentence processing............................................................................................ 24 Abstract ..................................................................................................................................................... 24 A time-based parser .................................................................................................................................... 27 Analysis of the repetition test...................................................................................................................... 30 References ................................................................................................................................................. 49 Egyeztetés agrammatikus afáziában................................................................................................................ 50 Absztrakt ................................................................................................................................................... 50 Irodalom .................................................................................................................................................... 61 Nyelvtan és Mentális Elemzõ Neurolingvisztikai Megközelítésben ................................................................. 63 MTA Nyelvtudományi Intézete .................................................................................................................. 63 Irodalom .................................................................................................................................................... 68 Semantic Bridging Effects in VP-Ellipsis........................................................................................................ 69 Introduction ............................................................................................................................................... 69 A preliminary overview of the data ............................................................................................................. 70 Semantic and pragmatic accounts of VP-ellipsis interpretation .................................................................... 73 A lexical semantic account of VP-ellipsis ................................................................................................... 74 Some relevant syntactic claims ............................................................................................................... 74 Ellipsis licensing with meaning postulates............................................................................................... 76 On the interaction of semantic parallelism and the organization of the grammar....................................... 78 Some further claims on the structure of the Lexicon .................................................................................... 79 Conclusion ................................................................................................................................................. 81 References ................................................................................................................................................. 81 The Interpretation of Universal Quantification in Child Language................................................................... 83 Aims and theoretical background................................................................................................................ 83 Preliminary overview of the data ................................................................................................................ 83 Philip’s (1995) experiments........................................................................................................................ 86 Experiments with Hungarian children ......................................................................................................... 88 Experiment 1.......................................................................................................................................... 88 Experiment 2.......................................................................................................................................... 90 Discussion of the Hungarian experiments and their implications.................................................................. 92 Conclusion ................................................................................................................................................. 93 References ................................................................................................................................................. 93 On the Semantic Interpretation of amikor ‘when’ and ha ‘if’ Clauses in Hungarian ......................................... 94 Introduction ............................................................................................................................................... 94 Comparing Hungarian ha ‘if’ and amikor ‘when’ clauses ............................................................................ 96 On the lexical meaning of akkor ‘when’ and ha ‘if’ ................................................................................. 96 Implicit quantifiers ................................................................................................................................. 97 Formalizing the semantic interpretation ...................................................................................................... 97
Basic ingredients .................................................................................................................................... 97 Formalizing the interpretation of amikor ‘when’ clauses.......................................................................... 99 Formalizing the intepretation of ha ‘if’ clauses ...................................................................................... 101 Conclusion ............................................................................................................................................... 102 References ............................................................................................................................................... 102 Coordinate Ellipsis as Phonological non-Insertion ........................................................................................ 104 Forward and backward ellipsis.................................................................................................................. 104 Ellipsis as deletion vs. reconstruction vs. anaphora.................................................................................... 106 BWE as phonological deletion — or morphological non-insertion ............................................................. 107 FWE as morphological non-insertion: The "meaning postulate" cases ....................................................... 112 Beyond meaning postulates? A further type .............................................................................................. 114 The true nature of the difference between BWE and FWE......................................................................... 116 Summary.................................................................................................................................................. 117 References ............................................................................................................................................... 117 Effect of verb complexity on agrammatic aphasic's sentence production........................................................ 119 Introduction ............................................................................................................................................. 119 Agrammatic sentence production .............................................................................................................. 120 Patterns of verb production ....................................................................................................................... 120 The present study ..................................................................................................................................... 122 Experiment I ............................................................................................................................................ 123 The structure of the verbs used in Experiment I..................................................................................... 123 Method .................................................................................................................................................... 125 Results ..................................................................................................................................................... 126 Effects of morphological complexity......................................................................................................... 128 Types of answers...................................................................................................................................... 129 Argument assignment and thematic hierarchy .......................................................................................... 131 (Agent (Experiencer(Goal/Source/Location(Theme)))).............................................................................. 131 Case assignment in isolated arguments...................................................................................................... 133 The calusal answers (Type B and C) ........................................................................................................ 133 Word order in the clausal answers............................................................................................................. 134 Summary.................................................................................................................................................. 135 Experiment II ........................................................................................................................................... 136 Test material ............................................................................................................................................ 138 Method .................................................................................................................................................... 139 Results of Experiment II. .......................................................................................................................... 140 Types of errors ......................................................................................................................................... 142 Summary.................................................................................................................................................. 142 References ............................................................................................................................................... 144 How to Cope with "Free Word Order": An Efficient Part-of-Speech Tagging Method for Hungarian ............. 146 Abstract ................................................................................................................................................... 146 Aspect and Argument Structure.................................................................................................................... 148 Introduction ............................................................................................................................................. 148 On Aspect ................................................................................................................................................ 148 Preliminaries ............................................................................................................................................ 149 The theory................................................................................................................................................ 153 Classification of verbs ............................................................................................................................. 153 Stative verbs ......................................................................................................................................... 153 Process verbs ........................................................................................................................................ 154 Accomplishment verbs.......................................................................................................................... 154 Achievement verbs ............................................................................................................................... 155 Classification of Verbs.......................................................................................................................... 156 External arguments and aspectual verb classes ...................................................................................... 157 Conclusion ............................................................................................................................................... 157 Footnotes ................................................................................................................................................. 157 References ............................................................................................................................................... 158 Deconstructing syllable structure.................................................................................................................. 159 Empty positions in the skeleton ................................................................................................................ 159 The skeleton-melody relationship.......................................................................................................... 159 Empty skeletal positions and the null hypothesis ................................................................................... 161 Syllable structure...................................................................................................................................... 163
Why have syllable structure? .................................................................................................................... 163 Problems with the standard view........................................................................................................... 164 Empty nuclei in the skeleton ..................................................................................................................... 166 Does the coda exist?................................................................................................................................. 168 Without codas .......................................................................................................................................... 170 Heavy versus light syllables .................................................................................................................. 170 Compensatory lengthening.................................................................................................................... 171 Against constituency ................................................................................................................................ 172 Conclusion ............................................................................................................................................... 174 References ............................................................................................................................................... 174 Phonotactic grammaticality and the lexicon .................................................................................................. 176 Introduction ............................................................................................................................................. 176 The SPE-a algorithm ................................................................................................................................ 178 The SPE-b algorithm ................................................................................................................................ 179 The Greenberg and Jenkins algorithm ....................................................................................................... 180 Summary.................................................................................................................................................. 184 Notes........................................................................................................................................................ 185 Bibliography ............................................................................................................................................ 186 Aspect and Argument Structure.................................................................................................................... 187 Introduction ............................................................................................................................................. 187 On Aspect ................................................................................................................................................ 187 Preliminaries ............................................................................................................................................ 188 The theory................................................................................................................................................ 191 Classification of verbs ............................................................................................................................. 192 Stative verbs ......................................................................................................................................... 192 Process verbs ........................................................................................................................................ 193 Accomplishment verbs.......................................................................................................................... 193 Achievement verbs ............................................................................................................................... 194 Classification of Verbs.......................................................................................................................... 195 External arguments and aspectual verb classes ...................................................................................... 196 Conclusion ............................................................................................................................................... 196 Footnotes ................................................................................................................................................. 196 References ............................................................................................................................................... 197 Ertékek azonossága-e az egyeztetés?............................................................................................................. 199 Bevezetés................................................................................................................................................. 199 Az unifikáció hiányosságai ....................................................................................................................... 199 Egyeztetés ............................................................................................................................................ 199 Szubkategorizáció ................................................................................................................................ 200 Általánosítás és típusrezolúció .............................................................................................................. 201 Jegy-érték párok mint tulajdonságok......................................................................................................... 203 Grammatikai viszonyok és mellérendelõ szerkezetek ................................................................................ 203 Az egyeztetés osztály-alapú elemzése ................................................................................................... 204 Határozottság koordinált NP-kben......................................................................................................... 205 Grammatikai viszonyok rekurzív definíciója ......................................................................................... 206 Összefoglalás és további lehetõségek ........................................................................................................ 207 A cikk fontosabb állításai...................................................................................................................... 207 További lehetõségek ............................................................................................................................. 207 Hivatkozások............................................................................................................................................ 208 A Magyar Igekoto Egyeztetese ..................................................................................................................... 210 Bevezetés................................................................................................................................................. 210 Alapfogalmak........................................................................................................................................... 211 Expletívum-e az igekötõ? ......................................................................................................................... 211 Milyen mondattani viszonyokról van szó? ................................................................................................ 212 A személy- és számegyeztetés hiánya ....................................................................................................... 213 Leírási kísérlet.......................................................................................................................................... 214 Hivatkozások............................................................................................................................................ 216 Representation of Linguistic Knowledge in GIN 99 ...................................................................................... 217 Introduction ............................................................................................................................................. 217 The GIN language.................................................................................................................................... 217 Motivation............................................................................................................................................ 217
Attribute/value structures...................................................................................................................... 217 AVSs and relations............................................................................................................................... 220 2.4 Representing relations in an AVS format......................................................................................... 221 Yet another fragment ............................................................................................................................ 223 Multi-AVSs and types .............................................................................................................................. 225 Multi-AVS type hierarchies .................................................................................................................. 225 The type resolution process................................................................................................................... 227 References ............................................................................................................................................... 229 Is Agreement Value Sharing? ....................................................................................................................... 230 Abstract ................................................................................................................................................... 230 Problems with unification ......................................................................................................................... 230 Agreement............................................................................................................................................ 230 Subcategorization ................................................................................................................................. 232 Generalization and type resolution ........................................................................................................ 232 Attribute/value pairs as properties............................................................................................................. 234 Grammatical relations and co-ordinate structures ...................................................................................... 235 Class-based analysis of agreement ........................................................................................................ 236 3.2 Definiteness in co-ordinate NPs....................................................................................................... 237 Recursive definition of grammatical relations........................................................................................ 237 Summary and further perspectives ............................................................................................................ 238 Main statements.................................................................................................................................... 238 Further perspectives.............................................................................................................................. 239 References ............................................................................................................................................... 241 Constructional CV phonology....................................................................................................................... 242 Abstract ................................................................................................................................................... 242 Construction phonology............................................................................................................................ 242 CV Phonology in a constraint-based setting........................................................................................... 242 Domain-final empty nuclei ................................................................................................................... 243 Intervocalic consonant clusters ................................................................................................................. 244 Domain-final consonant clusters ........................................................................................................... 246 Long vowels......................................................................................................................................... 250 Domain initial clusters.......................................................................................................................... 252 Exceptional domain final licensing........................................................................................................ 253 Constructions and the hierarchical lexicon............................................................................................. 254 Phonotactics and morphophonology.......................................................................................................... 256 Types of suffocation ............................................................................................................................. 256 General constraints on monomorphemic stems...................................................................................... 257 Epenthetic stems................................................................................................................................... 258 Lowering and exceptional licensing ...................................................................................................... 260 2.5 Synthetic suffixation ....................................................................................................................... 269 Verbal stems and synthetic suffixation .................................................................................................. 269 Pseudo-analytic suffixes........................................................................................................................ 271 References ............................................................................................................................................... 273 Kormányzás-fonológia kormányzás nélkül ................................................................................................... 275 A mássalhangzók engedélyezése............................................................................................................... 275 Valódi mássalhangzó-kapcsolatok......................................................................................................... 275 A kóda engedélyezése........................................................................................................................... 278 Az üres mag engedélyezése ...................................................................................................................... 283 Kivételes engedélyezés ......................................................................................................................... 283 Trocheikus engedélyezés ...................................................................................................................... 287 Engedélyezési tartományok................................................................................................................... 290 Köszönetnyilvánítás ................................................................................................................................. 292 Irodalom .................................................................................................................................................. 292 A helyelemek egyeztetése a CV-fonológiában .............................................................................................. 294 Bevezetés................................................................................................................................................. 294 Kormányzási tartományok ........................................................................................................................ 294 Valódi mássalhangzó-kapcsolatok......................................................................................................... 294 Szerkezeti párhuzamok ......................................................................................................................... 297 Asszimilációk........................................................................................................................................... 300 Hely-hasonulás mássalhangzók között .................................................................................................. 300
Abstract We analyzed some syntactic, semantic and phonological phenomena that presuppose the existence of interrelated components within the lexicon, which motivate the assumption that there exist some sublexicons within the global lexicon of a speaker. This result is confirmed by experimental findings in neurolinguistics. Hungarian speaking agrammatic aphasics were tested in several ways. The results showed that the sublexicon of closed class lexical items provides a highly automated complex device for processing surface sentence structure. Analysing Hungarian ellipsis data from a semantic-syntactic point of view, we established that the lexicon is best conceived of as split into at least two main sublexicons: the store of semanticsyntactic feature bundles, and a separate store of sound forms, and proposed a format for representing open-class lexical items whose meanings are connected via certain semantic relations. We proposed a new classification of verbs to account for the contribution of the aspectual reading of the sentence depending on the referential type of their arguments, and a new account of the syntactic and semantic behaviour of aspectual prefixes. The partitioned sets of lexical items are sublexicons on phonological grounds. These sublexicons differ in terms of phonotactic grammaticality. The degrees of phonotactic grammaticality are tied up with the problem of psychological reality: how many degrees of phonological grammaticality are native speakers sensitive to. We implemented a hierarchical construction network as an extension of the original General Inheritance Network formalism. This framework was used as a platform for the implementation of the grammar fragments. Keywords: mental lexicon, sublexicon, neurolinguistics, syntax, semantics, morphology, phonological grammaticality, construction network, inheritance, GIN.
Objectives
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Objectives The aim of the research was to give a description and analysis of the mental lexicon with particular reference to sentence processing, in an interdisciplinary framework consisting of three submodules. The main tasks were the following: Neurolinguistics submodule: Collection of spontaneous speech samples of agrammatic aphasics, construction of off-line test materials, testing aphasics and control subjects. Evaluation of the test results. Construction of models for lexical access and retrieval. Answering questions on the organisation of the mental lexicon, and as to nature of the most economical type of lexical access in an agglutinative language like Hungarian. Two articles. Theoretical submodule: Semantics: The description of what semantic principles, if any, determine the storage of certain lexical items, what semantically based strategies speakers use to substitute the inaccessible lexical items under normal conditions and in aphasia. Collecting child language data on logical vocabulary. Morphophonology: Answering questions on how we process forms showing stem and suffix alternations, how the phonological-morphological subsystems are organised, whether there are phenomena in language processing which support the concept of analytic–synthetic suffixation, whether phonological, morphological and lexical information has a role in selecting the grammatical form. Two articles. Computational linguistics submodule: Discussing the feasibility of the implementation of experimental results and theoretical analyses in Generalized Inheritance Networks. Computational and formal aspects of content addressable inheritance systems developed for the encoding of hierarchical construction networks with relations. Two articles. The objectives have been successfully achieved. Responding to the need for investigations in the domain of syntax on the part of other submodules, the scope of research in the original Semantics Submodule was extended in the course of the project to include topics on syntax as well, thus, the four submodules working in the framework of the project were the following: neurolinguistics submodule, syntax-semantics submodule, phonology submodule, and computational linguistics submodule. (This change in the organisation of the project was indicated in the Interim Report.)
Findings
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Findings Importance: Due to the structural properties of Hungarian (agglutinative morphology, relatively free word order) certain basic assumptions of the traditional models of the mental lexicon may well be called into question. We have elicited data from normal native and non-native speakers of Hungarian and agrammatic aphasic patients as well. Scientific significance, innovative character: We analyzed some syntactic semantic and phonological phenomena that presuppose the existence of interrelated components within the lexicon, which motivate the assumption on the existence of sublexicons within the global lexicon of a speaker. 1. This finding was confirmed by experimental results in neurolinguistics. We demonstrated that the sublexicon of closed class lexical items (store of grammatical formatives, inflectional endings, suffixes in the mental lexicon) is critical for Hungarian speaking agrammatic aphasics. Speakers access open class words (content words) and closed class items by two distinct access systems. The interaction of the two access systems provides a highly automated complex device for processing sentence structure. We characterised the representational complexity of the verbs in the mental lexicon and its effect on aphasics’ sentence production. The internal temporal structure of verbs and argument selection from the lexicon was also analysed. 2. We found that the two directional types of co-ordinate ellipsis, although displaying certain different properties, can be treated by the same syntactic mechanism: the non-insertion (rather than deletion or reconstruction) of phonological shapes to the terminal nodes in the structure. This presupposes a model of syntax with split lexicon and late vocabulary insertion. We also isolated a subclass of cases of forward VP-ellipsis which is licensed by the semantic relations of meaning equivalence and entailment between propositions, the conditions of which are encoded in the representation of the individual lexical items in the lexicon. We propose a classification based on three aspectual classes of verbs, which gives the right predictions for the obligatory presence of certain arguments and for the interaction of the verbs and the different referential types of the arguments in the event structure. 3. The partitioned sets of lexical items are sublexicons on phonological grounds. These sublexicons differ in terms of phonotactic grammaticality. The phonotactic grammaticality of a string of segments is a measure that refers to the extent to which a given string is a potential/actual lexical item. The question of how many degrees of phonotactic grammaticality are to be recognised phonologically is tied up with the problem of psychological reality: how many degrees of phonological grammaticality are native speakers sensitive to; and the possible partitioning of the lexicon into sublexicons on phonological grounds. 4. The primary goal was to model a hierarchical construction network enriched with the representation of relations that are the formal counterparts of correspondence relations in construction grammar. The implementation is the extended update version of the original GIN (Generalized Inheritance Network) framework.
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List of publications
List of publications Neurolinguistics submodule Bánréti, Zoltán 2000a. ‘Closed class lexical items in sentence processing. A neurolinguistic approach’. ms p 38. Submitted to Huba Bartos (ed.) Papers on the mental lexicon, Research Institute for Linguistics, Hungarian Academy of Sciences, Budapest. Bánréti, Zoltán 2000b. ‘Nyelvtan és mentális elemző neurolingvisztikai megközelítésben’ (Grammar and Parser from the point of view of neurolinguistics), ms p11. Accepted for publication: 50 éves a Nyelvtudományi Intézet (50th anniversary of the Research Institute for Linguistics). Ed: Mária Gósy, Budapest. Bánréti, Zoltán 2000c. ‘Egyeztetés agrammatikus afáziában. A szintaktikai fa metszése’ (‘Agreement in agrammatic Broca’s aphasia. The syntactic tree pruning.’) ms p15. Submitted to: Néprajz és nyelvtudomány (Ethnography and Linguistics), Eds: M. Maleczki and L. Büky. Szeged. Kiss, Katalin 2000. ‘Representational complexity of verbs and sentence production in agrammatic aphasics’, ms. Submitted to Huba Bartos (ed.) Papers on the mental lexicon, Research Institute for Linguistics, Hungarian Academy of Sciences, Budapest.
Syntax-semantics submodule Bartos, Huba and Beáta Gyuris 2000. ‘Coordinate ellipsis as phonological non-insertion’, ms. Submitted to Huba Bartos (ed.) Papers on the mental lexicon, Research Institute for Linguistics, Hungarian Academy of Sciences, Budapest. Gyuris, Beáta. 2000a. ‘Semantic Bridging Effects in VP-Ellipsis’. Submitted to Huba Bartos (ed.) Papers on the mental lexicon, Research Institute for Linguistics, Hungarian Academy of Sciences, Budapest. Gyuris, Beáta. 2000b. ‘The Interpretation of Universal Quantification in Child Language’. Submitted to Huba Bartos (ed.) Papers on the mental lexicon, Research Institute for Linguistics, Hungarian Academy of Sciences, Budapest.
Gyuris, Beáta. 2000c. ‘On the semantic interpretation of WHEN and IF clauses in Hungarian.’ To appear in Approaches to Hungarian VII. Ed: István Kenesei, JPTE: Pécs. Tóth, Gabriella. 2000. ‘Aspect and Argument Structure’. Submitted to Huba Bartos (ed.) Papers on the mental lexicon, Research Institute for Linguistics, Hungarian Academy of Sciences, Budapest.
Phonology submodule Rebrus, Péter. 2000a. „Kormányzás fonológia kormányzás nélkül”. [„Government phonology without government”]. Submitted to Huba Bartos (ed.) Papers on the mental lexicon, Research Institute for Linguistics, Hungarian Academy of Sciences, Budapest. Rebrus, Péter. 2000b. „A helyelemek egyeztetése a CV-fonológiában”. [„Agreement of place elements in CVphonology”]. Submitted to Huba Bartos (ed.) Papers on the mental lexicon, Research Institute for Linguistics, Hungarian Academy of Sciences, Budapest. Rebrus, Péter and Viktor Trón. 2000. „Constructional CV Phonology”. Submitted to Huba Bartos (ed.) Papers on the mental lexicon, Research Institute for Linguistics, Hungarian Academy of Sciences, Budapest. Szigetvári, Péter. 2000. „Deconstructing syllable structure”. Ms., Eötvös Loránd University. Submitted to Huba Bartos (ed.) Papers on the mental lexicon, Research Institute for Linguistics, Hungarian Academy of Sciences, Budapest. Törkenczy, Miklós. 2000. „Phonotactic grammaticality and the lexicon”. Submitted to Huba Bartos (ed.) Papers on the mental lexicon, Research Institute for Linguistics, Hungarian Academy of Sciences, Budapest.
Computational submodule Rádai, Gábor. 2000. „Implementing Construction Grammars in GIN”. Submitted to Huba Bartos (ed.) Papers on the mental lexicon, Research Institute for Linguistics, Hungarian Academy of Sciences, Budapest.
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List of publications
Csaba Oravecz, Péter Dienes, Zoltán Alexin and Tibor Gyimóthy. 2000. ``How to Cope with "Free Word Order": An Efficient Part-of-Speech Tagging Method for Hungarian'', abstract accepted for poster session at the Second International Conference on Language Resources and Evaluation, Athens, Greece, 31 May-2 June 2000. Final paper due on Apr 2 and will appear in the proceedings. László Kálmán and Viktor Trón. 2000. Is Agreement Value Sharing? Submitted to Natural Language and Linguistic Theory. English version of the paper presented at the conference titled ``A Magyar Nyelv leírásának újabb módszerei IV.'' [Modern methods in the description of Hungarian IV.], Version of January, 2000. László Kálmán and Viktor Trón. 1999a. Értékek azonossága-e az egyeztetés? [Is Agreement Value Sharing?] (co-authored with László Kálmán) To Appear. In: Proceedings of the Conference ``A Magyar Nyelv leírásának újabb módszerei IV'' [Modern methods in the description of Hungarian IV.] László Kálmán and Viktor Trón. 1999b. A magyar igevivő egyeztetése. [Agreement of the Hungarian Verb Carrier.] (co-authored with László Kálmán) To Appear. In: Proceedings of the Conference ``A Magyar Nyelv leírásának újabb módszerei IV.'' [Modern methods in the description of Hungarian IV.] László Kálmán and Viktor Trón. 1999c. Linguistic Representations in GIN (Unpublished manuscript)
Detailed dummary of the results of the reserach
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Detailed dummary of the results of the reserach The main research findings are going to be presented individually for the four research groups, including the Neurolinguistics submodule, the Syntax-semantics submodule, the Phonology submodule, and the Computational linguistics submodule.
Neurolinguistics submodule Participants: Zoltán Bánréti and Katalin Kiss. Types of sublexicons in the mental lexicon
Open and closed class lexical items in the mental lexicon and their role in sentence processing Sentence repetition tests In the course of sentence repetition tests our agrammatic aphasic patient gave answers that were suggestive of initial structure building operations. With respect to stress patterns, each target sentence was neutral in the test. Hungarian is an inflectional language where the verb assigns case to noun phrases by means of case endings that mark theta roles in surface structure. Our patient was tested with the help of the strategy of monitored repetition. The patient processed the sentence both syntactically and semantically, then attempted to produce an utterance which matched the phonological, syntactic, and semantic properties of the original utterance. The performance of our patient’s parser can be characterised as follows. In comparison with the target sentence, 1. it is possible for the parser to approximate the class of the target predicate, and its case frame is retrievable; 2. if a different predicate is retrieved, then the suffixes are those appropriate to the case frame of the "original" predicate; 3. if the predicate is missing, the parser stops; for instance, it cannot list only the NPs from the target sentence; 4. it is possible to fill one slot from the argument frame of the predicate with selectional restrictions that are the same as (or very much like) the original; 5. knowledge about missing, lexically or phonologically null arguments is manifest in further search attempts that either mention case endings without a content word, or link them to pronouns or neologisms, in repetition of case endings, or in compensatory speech. Grammaticality judgement tests We tested a total of five Hungarian Broca's aphasics. Our grammaticality judgement tests covered some relevant features of Hungarian syntax and the lexicon. Three interesting cases are worth attention in this respect: (i) there were some easy tasks, where the acceptability judgements of the patients coincided with the expected answers in 100 per cent of the cases; (ii) in some cases we witnessed guessing, since judgements turned out to be essentially random and chaotic from a statistical point of view; (iii) in some other cases we faced systematic misjudgement of the data, which means that acceptable sentences were judged as good in 100 percent of the cases but unacceptable counterparts were also judged as good in 100 percent of the cases or at least close to 100 percent. The distribution of judgements supports a time-based approach to a parser. The plausibility of an account based on asynchrony between syntactic and lexical processes is motivated in the following way. The parser produces a structural frame for all possible sentences. This syntactic frame contains categorised slots. When the configuration of surface case endings assigned
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Detailed dummary of the results of the reserach
by category of Verb to its complements and the configuration of other closed class items are in their active phase in the working memory, they define and open up syntactic slots for the content word filler. Content words would be generated by the lexicon and would be inserted into their slots in the syntactic frame. Impairments of the accessibility of closed class morphemes create syntactic difficulties. Normal activation happens at the expense of fast decay and, vice versa, normal decay happens at the expense of slow activation. Applying this theory to our data we find the following. Specific features of syntactic subcategories and closed class morphemes can be activated at a normal rate, but then they decay very fast, too early from working memory; or they can be retained at a normal rate, at expense of their slow activation in working memory. In the former case other specific lexical information has also not been investigated previously, when it was needed. In the slow activation case other specific lexical information in working memory is already gone when needed. The fast decay or slow activation of grammatical features and subfeatures causes a desynchronization in the building of syntactic structure. Syntactic slots are opened up too late or too early for the content word filler; when specific lexical information in working memory had not been activated yet or is already gone when needed. Therefore patients are not able to complete the analysis of stimuli, processing operations result in a merely sketchy and unfinished structure. Patients were aware of their unfinished analysis, they often made comments on it. This could lead to guessing responses on complex, non-local relations. Patients were able to use initial structure building operations involved in first pass parse for the correct judgements of easy tasks. In the case of normals, first pass parse must be tightly synchronised with a second major parsing module which extracts detailed and specific features of the category of arguments and the predicate. But fast decay or slow activation of specific, unprotected information in working memory can cause desynchronization between processing modules. The consequences are systematic misjudgements or guessing responses, depending on the type of grammatical error and the complexity of sentence to be judged. Since closed class items have to be integrated with their categorised slots in the syntactic frame, and open class (content) words have to be inserted into their categorised slots in the syntactic frame as well, these two kinds of integration require synchronisation, the synchronised activation of structure building elements in working memory for language. The slow activation or fast decay of closed class items leads to a desynchronization between syntactic slots opened up by closed class items and the active phase of content word fillers. Theoretical results Differences between memory time for open-class and closed class items are important for accessing items in the mental lexicon. Closed-class items may fade away so fast from memory that the construction of a proper NP or Sentence (for instance) is doubtful. Temporal deficits do not affect the initial structure building operations. Our tests present empirical evidence for the fact that syntactic and lexical processes are partially autonomous routines. This becomes apparent in the case of a working memory deficit. The type of elements affected by the temporal deficit do make a difference, however. When function word nodes are affected, the required pattern does not emerge. It appears only when phrasal category nodes are impaired. Although the patient’s restricted working memory time may not be sufficient to produce a full sentence representation, it is nevertheless sufficient for the judgement of a verb and a string of inflectional endings (related to that verb). This is compatible with the assumption that the patient has to trade the processing of surface form against lexical access. (Inflection is part of the surface parser module but we do not claim that this (sub)module would not be impaired.) Therefore we apply the first-pass parse hypothesis. The hypothesis of initial structure building operations has been proposed by a number of psycholinguists. In accordance with this hypothesis we
Detailed dummary of the results of the reserach
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assume that in the sentence repetition test an initial structural analysis is computed and is subsequently interpreted. This is followed by later processing operations involving constraints on the indexing of structures involving content lexical items. The first-pass parser protects some of the processed lexical and syntactic information during first-pass parse and a working memory deficit restricts further processing operations. The patients' performance in the repetition tasks showed that the verb is the starting point for the surface syntactic analysis. The patients never made both inflectional errors and errors in the choice of the main verb in the same sentence. Patients made inflectional errors when they were unable to retrieve any verb. If the patients approximated the class of the target verb, however, then its surface case frame was retrievable for them. The case frame assigns suffixes to associated nouns; and it does so even if the nouns to which the endings are to be attached cannot be correctly reproduced by the patients. It can be assumed that in the first phase of processing the parser selects surface syntactic information (subcategorizational frame of the verb, surface case frame, word order). Closed class elements provide a syntactic frame into which open class items are inserted in the course of sentence processing. In non-fluent aphasia the surface syntactic parser is too slow in processing closed class lexical items, so lexical information in the working memory is already gone when needed. The subjects are unable to integrate the output of the syntactic parser with the segments of the lexical process. Publications resulting from the research: Bánréti (2000a,b,c) in the List of publications
Representational complexity of verb in mental lexicon and its effect on aphasics sentence production "Picture description/action naming" tests We have investigated how Hungarian Broca’s aphasic patients can lexically select and retrieve verbs which differ in their representational complexity and how are they able to construe Verb Phrases and simple sentences using the target predicate. As elicitation task an off-line method, a „picture description/action naming” test was used; the data were interpreted in the theoretical framework of Government and Binding Theory. The structure of the verbs used in the tests Based on their argument structure complexities, the tested verbs of the present study formed three main groups. Thus, one-place intransitive predicates which take only one Agent or Experient argument, two-place verbs, and three-place predicates were involved in the tests. The verbal performance of two agrammatic Broca’s aphasic patients was analysed. Both patients are native speakers of Hungarian. Our elicitation method was an ‘action naming’ /’picture description’ test. The pictures represented the target verbs/actions. We regarded an answer to be ‘complete’ if the patients were able to build the whole Verb Phrase or sentence. It means that the verb and its complements were lexically accessible, the argument NPs were supplied with the appropriate overt case marker, noun-verb agreement was intact and nonterminal node deletion did not occur. Analysis of experimental results Comparing the distribution of the retrievable target verbs within each verb group we found the following ‘verb difficulty order’: simple 1-place > morphologically complex 1-place = transitive (2-place) > 3-place (with locative and dative complement) > 2-place with locative complement
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Access to the ‘simple one-place’ verbs was outstandingly successful. The lexical selection of the ‘two-place verbs with locative complement’ proved to be the most difficult for the patients (they could not retrieve any verb in this group). These predicates were directional motion verbs. The lexical representations of these verbs integrate mental knowledge related to the cognitive representation of space or spatial relations. These verbs include such contents as direction of the motion, place-coordinates, starting point and end point. This information is encoded in the semantic representation and thematic roles of the predicate. Processing of this information seemed to be more difficult for our patients, they produced marked selection disorder when attempting to produce these verbs. The ratio of the three-place verbs was lower in the sample than the proportion of the one-place and two-place verbs. The empirical results show that the ‘representational complexity’ of the predicate has a direct effect on the lexical accessibility of the verb for agrammatic aphasics. The complexity of the argument-structure of the verb (number of obligatory arguments) plays an important role in verb retrieval but it is not the only factor. The morphological and semantic representational complexity of the ‘one-place derived verbs’ and the semantic representational complexity of the ‘two-place locative’ verbs also had an effect on the lexical-semantic selection of the predicates. According to the ‘thematic hierarchy’ hypothesis, the argument structure of the verb is not only a set of arguments. It has its own internal structure which represents prominent relations that are determined by the thematic information of the predicate. Grimshaw suggested a protoargumentstructure which is a structured representation of arguments based on thematic hierarchy: (Agent (Experiencer (Goal/Source/Location (Theme)))) The subjects were able to produce arguments of every type (Agent, Theme, Goal, Benefactive) but a difference was found in the distribution of the type of arguments activated first. Activation of the arguments lower in the thematic hierarchy was more frequent than that of the more prominent arguments of a given predicate (e.g. Theme > Benefactive > Agent ; Theme > Agent; Goal > Agent). Two exceptions were found to this tendency, namely the Agent >Goal order in the ‘three-place locative’ group and the Agent > Theme order in the ‘transitive [+animate]’ group. Comparing the proportions of arguments, an outstanding contrast was found between the activation of Agent and Theme arguments in the ‘transitive [-animate]’ and ‘3-place dative’ verb groups. In the case of the ‘3-place locative’ group the Agent>
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Agrammatic performance can be interpreted by those asynchronic mechanisms that cannot function simultaneously between the level of semantic operations (activation of argument-structure and thematic information) and syntactic processing (procedures that construct the syntactic phrase structure and map the arguments/thematic roles into the syntactic frame). Publication resulting from the research: Kiss (2000), in the List of Publications
Ellipsis in sentence processing Agrammatic aphasics overuse the linguistic option of ellipsis in free conversation. Ellipsis is understood as the omission of the projection of V after a focused DP or a quantified DP in a surface syntactic string . The use of elliptic sentences in spontaneous speech can be considered as a kind of adaptation or reaction. Broca’s aphasic patients are aware of their reduced linguistic capacity, that is why they employ elliptical constructions. The role of this strategy is to prevent computation overload in the linguistic system. Employment of this strategy (among others) is optional rather than obligatory. Hungarian grammar allows forward and backward types of Verb Phrase ellipsis. Forward VP Ellipsis (FVPE) is interpretively dependent on its antecedent. The syntactic tree is complete. Syntactic and semantic features of lexical items are present in the ellipsis site, it is the phonological form that is not inserted. there is no need to assume the deletion of lexical items. Backward VP Ellipsis (BVPE) sites result from a deletion of lexical forms. There are identification asymmetries between forward and backward ellipses. Forward ellipsis sites contain lexical content throughout the derivation, but fail to undergo phonological form-insertion. Backward ellipsis sites result from deletion after form-insertion. Sentence repetition tests We tested the neurolinguistic reality of the identification asymmetries with respect to the direction of VPE mentioned above. Our subjects were agrammatic Broca’s aphasics. The test material involved co-ordinated sentences with VP ellipsis sites. Each test contained 15 sentences containing forward VP ellipsis and 15 sentences containing backward VP ellipsis. Two subjects were given the test three different times. Sentence patterns were filled with different (though equally frequent) words in each test but we did not change the sentence structures themselves. To repeat sentences patients were pursuing the strategy of monitored repetition involving two basic operations: (1) processing the heard utterances both syntactically and semantically, then storing them; (2) attempting to produce an utterance which matches the phonological, syntactic, and semantic properties of the original utterance. Analysis of data Identification asymmetries between FVPE and BVPE are relevant for real sentence processing operations as well. Repetition of BVPE imposed syntax/phonology interface requirements that exceeded the impaired capacity of the language processor with agrammatic aphasics. Producing co-ordinated sentences with FVPE in a repetition test requires the patients to store a content-based representation of the heard co-ordinated sentence, then convert it into a surface syntactic and phonological form. Supposing the processor builds structures from left to right, there was no built-in delay in the processes because of direction of ellipsis. Patients often mentioned elided VPs in overt phonological form at its correct position in the second conjunct. It was easy for them to reconstruct FVPE in overt phonological form. To produce a co-ordinated sentence with a BVPE in repetition test, it is necessary to recover the deleted lexical forms in the first conjunct. If structures are built from left to right, there is a built-in delay in the operations because of the direction and identification level of the backward VPE. Recovering is delayed, because the deletion is located in the first conjunct, but the phonologically realised licensing string is found in the second conjunct. Patients were able to repeat only the second conjunct in its correct grammatical form. The first elliptic conjuncts were often fragmented and
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ungrammatical. The elided VP in the first conjunct was rarely mentioned in its overt phonological form. Patients didn’t reconstruct the BVPE overtly in the first conjunct. This is because the demands of the task increased to the extent that exceeded the capacity of the impaired processor. Theoretical results Properties of sentence repetition in aphasia result from the operations of normal processing principles under exceptional circumstances, in the face of impaired computational resources. The data characterised above are relevant from the point of view of a time based parser. The differences are related to timing. Generally speaking, when a non-empty Verb appears, most of the pieces to properly assemble the clause are available. In case of backward ellipsis the question is how to build a sketchy structure for the FIRST clause without lexical material of a non-empty V-bar. In the case of forward ellipsis, the parser processes the lexical material of the antecedent V-bar in the first place, then tries to analyse an empty category later. The parser is able to determine an empty (elided) category with the help of surface structural parallelism. Forward ellipsis is easier for impaired speech, because the same category is used twice in two parallel structures but an overt lexical form is mentioned only once. Backward ellipsis is harder for a time based parser. Backward ellipsis means that an empty category is detected at first. At the very moment when a parser detects an empty V-bar there is no information about its subtype and no information about the lexical material of the V-bar. The necessary decision is postponed. The parser must put that empty category into the memory buffer and wait for a posterior lexical item, namely lexical material of the posterior V-bar in the second clause. After processing the posterior V-bar the parser tries to determine the identity of the phonological form of the posterior V-bar and the elided V-bar and copy back the semantic/syntactic features. Backward ellipsis must cause a delay in structure building operations with the first co-ordinated clause. A hypothesis on the structure of the mental parser Suppose the following structure-building operations. The mental parser must produce a structural frame for all possible sentences. This syntactic frame contains categorised slots. When the configuration of surface case endings assigned by the category of Verb to its complements and the configuration of other closed class items are in their active phase in working memory, they define and open up syntactic slots for the content word filler. Content-words would be generated by the lexicon and would be inserted into their slots in the syntactic frame. Because closed class items have to be integrated with their categorised slots in the syntactic frame, and open class (content) words have to be inserted into their categorised slots in the syntactic frame as well, these two kinds of integration require synchronisation, a synchronised activation of structure building elements in working memory for language. The slow activation or fast decay of closed class items leads to a desynchronization between syntactic slots opened up by closed class items and the active phase of content word fillers. We define the mental parser as an automaton which becomes specialised in the processing of categories and features involved in the grammatical representation of sentences. Under this view the parser is a device which transfers information between a grammatical representation and a message level representation. The parser computes the grammatical representations of sentences and transforms them into a message level representation (at which the „what is to be said” is represented). The category and feature system is hierarchical in the grammatical representation. It has various levels of sub- and sub-sub categories, from the bare category to the individual lexical item and from the closed class category to the fully specific features of that closed class item. Then, it is the question of capacity and synchronisation how far down the hierarchy in grammatical representation the parser goes on its search for information. The distribution of patients’ performance in tests reflects the limitations on the interface between the impaired parser and the grammatical representation containing a hierarchy of categories and their features.
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For publications resulting from the research see the paper Bánréti (2000a,b) in the List of publications
Syntax-semantics submodule Participants: Beáta Gyuris, Gabriella Tóth
Ellipsis and the structure of the lexicon The aim of the syntax-semantic research group was to contribute to the general research aim of the project, the investigation of the internal structuring of the mental lexicon, from a syntactic and semantic perspective. More particularly, this meant isolating some of the sub-lexicons which are distinguished from the others in terms of syntactic and semantic behaviour. Structures containing ellipsis have always been in the forefront of the interests of syntacticians and psycholinguists, since the production and the understanding of structures which contain a „missing element” can shed a lot of light on the principles of mental computation, and the knowledge of grammar. Since the neurolinguistics subteam of our project group decided to investigate the mental lexicon of aphasic speakers by testing their comprehension and production of sentences containing ellipsis, in order to foster internal communication and co-operation within the project, instead of dealing on the three individual research topics as specified in the proposal, we concentrated, from the beginning, on the semantic analysis of Hungarian sentences containing ellipsis as a means of fulfilling our original research objectives. (The change of perspective was already indicated in the Interim Report.) In the domain of syntax, we examined a wide range of ellipsis types, in order to explore the mechanisms underlying ellipsis phenomena. In particular, we wished to test a grammar model based on the theory of Distributed Morphology (Halle & Marantz 1993), in which ellipsis is implemented as the non-insertion of phonological shapes to certain (strings of) lexical elements. This approach, stemming from work by Wilder (1997) and Bartos (to appear), abandons the traditional analyses of ellipsis, which were set in terms of either phonological deletion, or the content reconstruction/interpretation of syntactically null elements, and places it in the context of a model, in which what used to be seen as a unitary lexicon is split up into two (or even three) separate lexical modules: one containing the lexical items as semantic-syntactic feature bundles, and another one which contains sound forms, which are to be associated with the formal featural lexical items after the syntactic derivation. (A third possible lexical module would contain idiomatic meaning units, to be associated with the lexical items postsyntactically.) In the first phase, we carefully studied the relevant literature within the generative grammatical tradition, to have a firm grasp on existing analyses of ellipsis (study trip by B. Gyuris to Edinburgh). On the basis of a summary of this, we examined data from Hungarian, to establish what languagespecific properties are involved, so as to be able to abstract away from such particularities. These data also served as the primary area of our own analyses. The results and findings of this stage were presented at a group meeting, for the whole project group. We analysed VP-ellipsis data from Hungarian and English (taking this type of ellipsis to be representative), where we found that functional items do not behave uniformly under ellipsis: formal agreement items show much wider variability between ellipsis targets and licensers than tense/mood markers, which essentially pattern with open-class items, i.e. content words. In the second phase, we focused our attention on the comparison of backward and forward ellipsis (i.e. whether the elided material is in the first or the last conjunct in a co-ordinate structure). These two subtypes have often been treated by different analyses, due to the fact that they display characteristically different properties: while in backward ellipsis the elided part must be fully formidentical to the parallel part of the final conjunct, for forward ellipsis the constraints are less strict — e.g. full form-identity is not (always) required. Instead of following the mainstream, which attributes this difference to different executions of elision (deletion under identity vs. reconstruction under
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semantic/pragmatic equivalence or entailment, or anaphor interpretation) (a review of these is found in Gyuris 2000a), we attempted to assimilate the two types to the greatest possible extent. We have shown (Bartos–Gyuris 2000) that some seemingly complicated non-identity cases of forward ellipsis can be handled without recourse to less well-defined notions like reconstruction/interpretation, with the simple licensing mechanisms for phonological non-insertion used for strict form-identity ellipsis, by relying on meaning postulates, i.e. equivalence/entailment relations between lexical items (such as inversion of argument linking, or detransitivization), which can be encoded in the lexicon in a simple and exact fashion. The scientific significance of our findings consists in two main points: (a) the success of these analyses gives strong support to the split lexicon hypothesis (see above), by virtue of the fact that our efficient theory of ellipsis is set in the context of such a model of grammar; and (b) our approach to the problem of ellipsis opens up a perspective to incorporate further particular problematic ellipsis types into the non-insertion analysis, thereby facilitating the understanding of the phenomena in order to arrive at a more unified treatment for ellipsis types. Furthermore, the application of meaning postulates (cf. Gyuris 2000a, on the semantic aspects of ellipsis) presupposes that there exist sublexical networks linking lexical items via such equivalence/entailment relations — another piece of contribution to the understanding of the structure of the so-called “mental lexicon”. The papers resulting from the research are Bartos and Gyuris (2000), and Gyuris (2000a) in the List of Publications
The interpretation of certain logical vocabulary items in adult and child usage It was discovered by Philip (1995) that the interpretation of certain determiner quantifiers differs in the adult and child language of English and Japanese speakers, and suggested that the reason for this is that as opposed to adults, children seem to quantify over minimal events, just like it is done in the case of adverbial quantifiers by all speakers. We carried out two experiments with children aged between 4 and 7 year in the framework of the project to find out whether Philip’s (1995) predictions would also hold for Hungarian speakers. Although we found recurring patterns among the data produced by Philip’s subjects and ours, we did not find evidence for the same developmental stages in employing event quantification as Philip claimed to characterise his subjects. His arguments for the more nature of event quantification also did not seem to be convincing enough, due to the obvious conceptual differences between the tangible objects adults are supposed to quantify over and the more abstract events children are supposed to operate with. Consequently, we proposed an alternative account of the facts, according to which in child language all determiner quantifiers are represented in a similar way, namely, as insensitive to the order of their arguments, while, at a later stage, the conceptual distinction between strong and weak quantifiers develops. We believe that the account proposed by us gives a much more credible explanation for the data than assuming the conceptually complex event quantification to operate in child usage. The paper resulting from the research is Gyuris (2000b). We investigated the meaning of a different pair of logical vocabulary items, namely the connectives amikor ‘when’ and ha ‘if’ as well, in order to find out how the similarities and differences in the interpretation of sentences containing them can be accounted for in terms of their lexical representations. It is important to note that the use of vocabulary items corresponding to amikor ‘when’ and ha ‘if’ shows some crosslinguistic differences, for example, the so-called „atemporal” use of whenclauses is impossible in Hungarian. Our investigations therefore aimed at discovering the universal and the individual aspects of the meaning of these items.
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After having studied the interpretation of sentences with subordinate clauses introduced by the above connectives with or without adverbs of quantification in their main clauses we established that amikor ‘when’ and ha ‘if’ clauses are always interpreted as expressing quantification over sets of eventualities and n-tuples of possible worlds and eventualities or individuals, respectively. This difference accounts well for the factivity of amikor ‘when’ clauses and the lack of it in ha ‘if’ clauses. The lack of atemporal readings for amikor ‘when’ clauses was explained by the fact that the particular temporal relations which determine the temporal ordering between the runtimes of eventualities satisfying the descriptions in the main and subordinate clauses are not defined for a certain subclass of states, which property does not extend to cross-lingusitic equivalents of these words. The paper resulting from the research is Gyuris (2000c).
Aspect and Argument Structure The goal of the project was twofold. On the one hand, we wished to examine the different types of events with respect to the internal temporal structure of the predicate, the referential types of their arguments and the thematic roles that relate the arguments to the event. On the other hand, we aimed to study the argument structure on the basis of the internal temporal structure of the verb It has been proposed by several linguists that telicity and atelicity are not the property of the sentence but the property of the verbs. Vendler and Dowty classify verbs into four major aspectual classes (statives, processes, accomplishments and achievements) while Verkuyl and Krifka distinguish stative events from dynamic events. Events are composed on the basis of the temporal property of he verb and the referential type of the arguments. Verkuyl (1989, 1993) observed that the Dowty-Vendler classification is a highly problematic because a well defined group of verbs, namely process verbs have to be listed in the lexicon twice as process verbs and as accomplishment verbs depending on the referential type of their arguments (cf. John ate an apple vs. John ate apples). Verkuyl-Krifka approach can account for the above problems by simply claiming that there is one verb listed in the lexicon and telic events are composed of a dynamic verb and quantified nominal arguments while atelic events are composed by either stative verbs and their arguments or dynamic verbs and their bare existential arguments. There is, however, also a serious problem with the compositional approach developed by Verkuyl, since in some cases bare nominals can occur in telic events if they are combined with achievement verbs (e.g. John found money in the garden). To avoid the above mentioned problems, we propose a new classification of aspectual verb classes on the basis of the internal temporal structure of verbs. We claim that verbal predicates are classified into three basic aspectual classes in the lexicon. Stative verbs do not consist of atomic events, process verb do, but the number of atomic events in their case is unlimited, while achievement verbs consist of exactly two atomic events. Accomplishments are composed of process verbs and quantified nominal arguments in the spirit of Verkuyl (1993). We propose that only dynamic verbs can be delimited by introducing a direct internal argument of a certain type, that by undergoing some change of state delimits the event. Statives cannot have this type of argument at all. Statives can never be delimited, process verbs can, but, as the number of atomic events process verbs can contain is unlimited, they need a well-defined direct internal argument, a quantified DP that can delimit the event temporally. Achievement verbs differ from process verbs with respect to their internal temporal structure as they consist of exactly two atomic events. They can temporally delimit the event, but to encode the change of state achievement verbs need a direct internal argument. As the verbs can temporally delimit the event, the internal argument need not be quantified, it can be a bare existential. We have also established process verbs may, but achievement verbs must have an internal argument. If process verbs occur in a telic event, the presence of the direct internal argument is
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obligatory. Neither achievement verbs nor process verbs form one homogeneous class. Only those direct internal arguments can delimit an event whose subparts have a unique relation with the atomic events (to eat, to drink, to destroy, to create, to paint), those direct internal arguments, whose subparts do not have this type of relation (to hammer, to run) cannot delimit the event. These verbs can have another indirect internal argument (a small clause or a directional prepositional phrase). External arguments can occur only with dynamic verbs. We assume Kratzer (1995)'s analysis on the status of the external argument. They claim that the external argument is not the argument of the verb. It is argument of a predicate they call CAUSE that can be combined with the verb in the syntactic representation. We will assume that this combination is possible if the verb is dynamic. The major significance of our findings lies in the proposal for a new classification of verbs on the basis of their internal temporal structure. This new classification eliminates the redundancy of the Vendler-Dowty classification, and gives the right results with the achievement verbs (problems that arise in the Verkuyl-Krifka theory) that heavily relies on the referential type of the internal argument in the calculation of (a)telic events. The theory further predicts the presence of external, direct internal and indirect internal arguments with minimal information about the verbal predicate. The paper resulting from the research is Tóth (2000) in the List of Publications.
Phonology submodule Participants: Péter Rebrus, Péter Szigetvári, and Miklós Törkenczy The research conducted clusters under three topics. Firstly, we have examined theories about degrees of phonotactic grammaticality, including an excursus on a related issue, paradigmatic defectivity. Secondly, we have improved a theoretical framework of phonological representation that is adequately restricted, but, nevertheless, is more or less capable of capturing phonotactic patterns in an abstract model. Thirdly, by proposing a formalization of the theoretical model the framework can be embedded in a concept of the hierarchical lexicon.
Degrees of phonotactic grammaticality: partitioning the lexicon The question of how many degrees of phonotactic grammaticality are to be recognized phonologically is tied up with the problem of psychological reality (How many degrees of phonological grammaticality are native speakers sensitive to?) and the possible partitioning of the lexicon into sublexicons on phonological grounds (Are there partitioned sets of lexical items that differ in terms of phonotactic grammaticality?). These are the main research questions of this topic. While phonotactic graduality is conceivable in a homogeneous lexicon, a theory of sublexicons constituting the full lexicon of a language changes the picture. The properties of the existing two-level and multi-level models of phonotactic grammaticality were explored. These models were all found unsatisfactory in various ways. An attempt was made to delimit the theoretical dimensions of a phonotactic grammar, i.e. to theoretically identify the factors and their interaction involved in phonotactic grammaticality. The factors considered were: the direct vs. indirect nature of the algorithm, the role of the number of violations in the evaluated string, the role of (type and/or token) frequency, and the "structuredness" of the lexicon. The results were reported in Törkenczy (2000). Examining Japanese, Ito & Mester (1995) conclude that the lexicon is organized by partly overlapping constraint domains, lexical strata are defined by sets of items that are subject to different phonotactic constraints and phonological rules. The existence of such sublexicons within the global lexicon of a speaker may be manifested in differences in the speed of activation, therefore the analysis of the speech of aphasiacs provides empirical evidence for detecting the existence and extent of the different sections of the lexicon. It follows from assuming such an organization of the lexicon that phonotactic constraints cannot result in simple yes/no choices in grammaticality, i.e., the assumption that a given string is
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either fully well-formed or fully ill-formed has to be abandoned. The phonotactic grammaticality of a string of segments is a measure that refers to the extent to which a given string is a potential/actual lexical item. In fact, unless a sublexicon is always a subset or a superset of another sublexicon (which is not what Ito & Mester assume), phonotactic graduality cannot be implemented. Within such a model the phonotactic grammaticality of a given item can only be given relative to some sublexicon, i.e., a form is not grammatical or ungrammatical and not more or less grammatical, but grammatical or not according to the constraints that prevail in a given sublexicon. Phonotactic constraints may even restrict the operation of apparently independent morphological processes. In the first half of the research period it became increasingly clear that verbs are a phonotactically identifiable subgroup of the Hungarian lexicon. There are several indicators of this: a)
verb stems can only end in a set of consonants clusters which is a subset of the clusters permitted at the end of stems in general;
b)
(synthetic) suffixation may only create verb-final clusters that are a subset of the clusters that can result from (synthetic) suffixation at the end of words in general (compare suffixation of nouns by accusative -t with the suffixation of verb by past tense -t);
c)
verb-stems may end in clusters that are not permitted word-finally. These stems are not only bound, but lack all forms that contain analytic suffixes. Thus, these verbs are defective in that they have a defective paradigm. Furthermore, the defectivity of this group of stems is phonologically motivated, i.e. not arbitrary.
Defectivity is thus an important characteristic of a subset of items in the Hungarian lexicon. The behavior of these stems was analysed within the framework of a nonderivational phonological model (Government Phonology) and it was proposed that the paradigmatic gaps are due to the fact that defective verbs do not have a lexical stem, while their synthetically suffixed forms are stored in the lexicon. These results were presented in Rebrus & Törkenczy (1998, 1999). In the second half of the research period the phenomenon of defectivity was explored. Phonologically motivated defectivity is not a well-researched topic and at first appears to be a rare phenomenon. Nevertheless, a thorough search in the international phonological literature revealed that there are several examples of phonologically motivated defectivity in a variety of languages (e.g. Tagalog: um- infixation/prefixation; Catalan: hypochoristics by truncation; Turkish: minimal size constraint on suffixed forms; Swedish: paradigms of /dd/-final adjectives and verbs; English: -ize suffixation, verb-forming -en suffixation; Russian: 2nd conjugation verbs, etc.), and more importantly, that there are different types of phonologically motivated defectivity. The Hungarian case is especially interesting because the motivating factor is a general phonotactic constraint which true of the possible phonological forms in the language across the board. Compare, for example the productive English verb-forming suffix -en, which can only attach to obstruent-final stems (dampen, redden, loosen, etc) while sonorant-final adjectival stems will not have corresponding -en verbs (*coolen, *greyen, *thinnen, etc.). This is a case of phonologically motivated defectivity which is different from the Hungarian case because the excluded forms in English are not phonotactically illformed (compare woollen, swollen etc). Our research suggests that defectivity in general, and the case of Hungarian defective verbs in particular, is problematic for Optimality Theory, even when the theory is "fixed up" with devices specifically designed to handle absolute ill-formedness. The results of this research were presented in Törkenczy 1999. VC phonology Dienes & Szigetvári (1999), Szigetvári (1999) and Dienes (in prep.) are devising a theory for explaining the plausible sites and direction of consonantal lenition and its absence and phonotactic constraints.
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Detailed dummary of the results of the reserach
Lowenstamm (1996) claims that the phonological skeleton consists of strictly alternating C and V positions, i.e., any consonant or vowel cluster encountered in the interpretation of a phonological string is separated by a vocalic or consonantal position, respectively, in its representation which fails to be interpreted phonetically. The theory presupposes a fairly abstract definition of skeletal position, one which allows it to remain unmanifested in pronunciation, there is, nevertheless, reason to accept this stance, some arguments are offered in Szigetvári 2000. Ségéral & Scheer's (1999) offer a theory of consonant lenition involving CV skeletons. Their aim is to apply the partly redefined notions of government and licensing to explain why word-final and intervocalic consonants are more prone to lenition than those in word-initial and postconsonantal position. The theory suffers from some weak points though, the set of governing and licensing relationships proposed to hold between units of the skeleton appears to be incomplete, not providing for a number of well-attested cases (like long vowels or the type of falling-sonority cluster that occurs word-finally in languages like English or Hungarian, as opposed to other clusters that do not). These are among the problems that are addressed by VC Phonology. The novelties of the theory are: (i) an explicit formulation of what consonantalness and vocalicness means in CV frameworks, (ii) an explicit definition of the two prosodic forces, licensing and government and (iii) the claim that the skeleton of each domain in phonological representations begins with a V position and ends with a C position. It is claimed that the inherent property of C positions is that they are mute, thus remain unpronounced unless external influence forces them to be phonetically interpreted. As opposed to this, V positions are inherently loud, that is, it takes an effort to silence V positions on the skeleton which fail to be pronounced. The notion of government is redefined: instead of inhibiting the expression of melodic content (an effect identical to the absence of licensing} as in Ségéral & Scheer's theory, it is claimed to destroy the inherent properties of its target. Thus a governed consonant becomes louder, a governed vowel becomes muter. Lowenstamm's CV framework has inherited the concept of word-final empty nucleus, an empty vocalic position posited at the end of consonant-final words, from Government Phonology. This position, however, remains silent only because of a stipulative clause, which, furthermore, is language specific. VC Phonology denies the existence of this position, instead, it posits an empty consonantal position at the end of vowel-final words. The superiority of this solution is that the noninterpretation of a consonantal position needs no special care. The relevance of the theory for the current project is the fact that it provides a relatively coherent theory of phonological representation, which aims at explaining phonotactic constraints, a feature of the lexicon that appears to have an important role in defining the sublexicons. The parameters that influence the grammaticality or lack thereof of phonological strings are often seen to hold in certain subcomponents of the lexicon and reset in others.
Phonotactics and morphological complexity On the basis of phonotactics languages can be divided into different types. In our view this typology of languages is based on the inventory of specific phonological constructions used by the given language. For instance the prosodic typology roughly presents the following types of languages: (i) CV-languages (ones which only have words containing CV sequences), (ii) the so-called Princelanguages (in which a limited set of homorganic consonant clusters are allowed), (iii) languages in which almost every cluster is allowed intervocalically, (iv) languages with long monophthongs or diphthongs, (v) languages which allow domain-final consonants, (vi) languages which allow a limited set of consonant clusters domain-initially (or postconsonantally), (vii) languages which have vowels in the beginning of the word (or in hiatus). A language can be a member of one or more of the types mentioned above. For a language, however, these properties cannot be selected randomly: certain properties must involve others (these relations are called universal implications). For instance (iii) naturally involves (ii), and (iv) involves (ii), also (i.e. if there are long vowels, there must be closed syllable). Between (ii) and (v), however, there is no such implication; the same as between (vii) and (ii)/(iii). Such implications limit the number of the possible language types, and a
18
Detailed dummary of the results of the reserach
morphophonological theory has to include a proper formalism which expresses these implicational relations. Markedness relations can be easily expressed by phonological constructions. The availability of a certain construction makes a language more marked than one lacking it. This way we can establish markedness relations between languages in several dimensions. These markedness relations, however, usually appear within a language, too. The results of certain morphological processes can be different from monomorphemic forms (stems) in their phonotactics. In the simplest case there is a twofold distinction: some morphologically complex (e.g. suffixed) forms have the same phonotactics as monomorphemic forms. Other morphological complex forms, however, have looser phonotactics than monomorphemic forms, hence these forms could not be stems. This latter type of suffixation is exemplified by analytic suffixation. This does not mean that the phonotactics of analytic forms is unlimited: there are constraints which cannot be violated in analytic forms, either. These constraints are either static (i.e. restricting the range of possible morphemes) or dynamic (i.e. the so-called postlexical processes which are automatically triggered). In languages with more complex morphological structure, the simple twofold distinction between analytically and non-analytically suffixed forms is to be refined. In Hungarian, for instance, different non-analytic forms suggest a different phonotactics. This can be explained if one assumes different types of specific classes of suffixes may select a different range of phonological constructions as available for the entire suffixed form. Moreover, there are stems which are irregular in terms of their non-productive alternations in their non-analytic suffixed forms. Similarly to the suffixes, specific "irregular" classes of morphemes can "refer" to a more or less arbitrary range of constructions which determine their suffixed forms. With these assumptions we obtain a highly structured lexicon, where the phonological representation of different suffixed forms are parsed by constructions, the inventory of which may be limited by the individual suffix- as well as stemmorpheme classes. Our approach to the formalisation of phonological representations relies on the results of CV phonology (Szigetvári 2000). Rebrus (in press) gives a detailed analysis of a great deal of Hungarian morphophonological phenomena in Hungarian within a CV phonology framework. Rebrus & Trón (2000) is an attempt to reformulate some results of CV phonology in the context of construction grammar. Phonological constructions referred to above are thought to reflect various licensing configurations in CV phonology. Motivated by our findings in Hungarian morphophonology, it seems worthwhile to integrate a framework of sufficiently abstract phonological representation with the conception of a hierarchical lexicon. This conception of an intricate lexical hierarchy fits well the overall architecture of grammar advocated by lexicalist grammars, such as Construction Grammar (cf. Rádai 2000). Also, it lends itself to a plausible implementation in the GIN (Generalized Inheritance Network) framework of linguistic representations (see the section on the computational submodule). On the other hand, the grammatical architecture reflects the structure of the mental lexicon: the existence of various subsystems of available phonological constructions parallels the gradual nature of phonotactic grammaticality judgments (Törkenczy 2000). The different phonotactics of morphologically complex forms can give essential clues needed in morphological parsing processes. Apart from theoretical considerations the importance of such a representation of phonological forms lies exactly in this fact.
Detailed dummary of the results of the reserach
19
Computational linguistics submodule Participants: Csaba Oravecz, Gábor Rádai, Viktor Trón
Representation of linguistic knowledge The architecture of the lexicon A thorough investigation into mainstream ideas on lexical matters as well as a critical examination of various treatments of all kinds of grammatical phenomena suggesting lexical restrictions have led us to serious conclusions concerning a plausible organisation of the lexicon and its relation to the language faculty as a whole. We take a radically lexicalist stance. We claim that if the lexicon is needed to store the unpredictable sound-meaning correspondences, anyway, then it is all we need. Instead of the rules of grammar, or derivations, what is crucial here is solely the organisation of information. This parallels with the standard requirement for scientific theories, that is the assumption of a minimal ontology. Construction Grammars in GIN It has been around for a while that syntactic constructions previously thought of as being generated by phrase-structure rules or the like are nothing more (or less) than correspondences between form and meaning ((Goldberg 1995), (Jackendoff 1997), (Fillmore and Kay 1993)). With the obvious difference that here items are more complex (more structured) in the general case than that of, say, monomorphemic stems. Given that the representational language of the interface modules should be able to express phonological and semantic information, (constituency relations: the analysis of the item into parts) as well as the devices for underspecification, the representation of more complex items is nearly trivial. Now the concept that has traditionally been associated with the term `lexical item' suddenly dissolves and what we are left with instead is a set of sound-meaning correspondence-rules. The generality of a correspondence statement is no more a categorical attribute of a construction, as in the case of a syntactic rule, rather, it is best thought of as attaining a measure of degree. On one end of the scale there are the most general constructions that involve as their „constituents” very generally characterised (lexical) classes, possibly including open classes. On the other end of the scale we have fully lexicalised patterns that — even if they fit in the lexicon as a special case of some general construction, and therefore have similarly structured relatives — have idiosyncratic, (unparalleled, exceptional, unpredictable) features. What we are provided with now is one quite intricately woven hierarchical network of grammatical constructions, one which establishes the inextricable link between the interface levels of language, on the one hand, while still retaining their relative autonomy of the representational levels, on the other. This autonomy manifests itself in the fact that the interface levels are representational modules complying with the principle of representational modularity. Sublexicons We have found that some phonological phenomena presuppose the existence of various interrelated compartments within the lexicon, which motivate the assumption of sublexicons in the mental lexicon. This finding is confirmed by experimental results in neurolinguistics. This phenomenon defies an adequate description, let alone an explanation, given a not very carefully worked-out notion of the lexicon as a non-redundant list of idiosyncratic features of atomic items. Instead, this problem lends itself to a solution within a hierarchically structured lexicon, where morphosyntactic, semantic and phonological information is equally present and related by
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Detailed dummary of the results of the reserach
correspondence constructions. These correspondence constructions, being underspecified to an arbitrary extent, represent lexical classes. Their partial subsumption order in turn can express the relevant generalisations across these lexical classes or can allow special subcases within each. With this emerging view of lexical architecture, we hope to have provided the formal setting for the intuitive idea of sublexicons. Our primary goal then was to model such a hierarchical construction network but to allow for the representation of relations that are the formal counterparts of correspondence constructions. Therefore we chose to implement it as an extension of the original GIN formalism.
Extension of the GIN formalism AVSs and relations Inheritance networks have become the major tool of knowledge representation in AI over the past decades. This naturally lead to the assumption - realised in the framework of Head-Driven Phrase Structure Grammar (HPSG) - that linguistic knowledge should also be stored in this form. This formalism had an important new feature over former frameworks such as DATR: whereas in the latter one could query the network in the old fashioned AI form - namely by naming the object and the property one wished to have information on -, the former framework made an important concession to the different way in which linguistic knowledge is put to use. HPSG is based on the assumption that our linguistic knowledge has the form of constraints - namely which form goes together with which meaning. Thus all linguistic tasks - such as generation and parsing - consist of finding and instantiating the constraints a given structure is subject to. This is to say that we query the network via certain keys given in the - syntactic or semantic - description of the structure in question, i.e., carry out a content oriented search of a database. In this framework the above concept of a relation can not be properly encoded. The standard „tricks” usually employed to get around this problem (such as the introduction of set values or indeterminate feature names) all lead to extensions of the formalism in which the basic operation on AVSs, unification is not well-defined and/or the algorithm deciding the equivalence of two AVSs has a rather high complexity (Kálmán and Trón 1999a). The formalism worked out under the RSS grant had the goal to overcome some of the inherent limitations of the above system. Most importantly the drawback that HPSG networks are a continuation of the AI tradition inasmuch as they only allow information about (classes of) objects to be encoded. We have come to the conclusion that in linguistic applications it is often necessary to represent relational information and extend inheritance to relational nodes (see Kálmán and Trón 1999a, 1999b). This led to the birth of the formalism of Generalised Inheritance Networks (GIN). The first year of the project was taken up by designing and implementing the above system. As we pointed out above, we considered it to be the major limitation of systems using Typed Feature Structures (TFS) - such as HPSG - that they do not allow for the direct representation of relational information that plays an important role in representing linguistic knowledge. Thus we had to come up with a system that fits this purpose. Since TFS's have proved an efficient representational tool for inheritance relations in the form of type declarations, we chose to use this formalism as a point of departure and to enrich it for our purposes. The basic idea was to interpret all nodes of the network as a description of n-ary relations — thus the old class-descriptions simply become border cases in terms of being unary relations, i.e., properties. This gives us the opportunity to describe relations and inheritance relations on them directly. The language of TFS's had to be enriched to allow for n-ary features and n-ary type declarations. The expressive power of the RAVS (Relational Attribute Value Structure) language is between the AVS language and positive first order logic, enables the expression of relational information. The algorithm deciding the identity of two AVSs having
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Detailed dummary of the results of the reserach
Type resolution Partially specified RAVSs are structured according to subsumption in a type hierarchy. Standardly presuming the closed world assumption whereby general types stand for the disjunction of their most specific instances. Naturally the values of attributes as well as relations can be (under)specified and can refer to a type. The network can then be thought of as a generative grammar, in which the well-formed structures are those in which all referenced types are resolved to at least one most specific instance. The advantages of such a highly homogeneous and declarative representation of linguistic knowledge is exactly that however rigid it may be with respect to formal representations, it is highly flexible with respect to a software implementation. We believe that the details of the actual type-resolution algorithm could be adjusted in a way so as to enable experimental research on modelling at least some aspects of human language processing and parsing. We can index the network and use pointers to drive the search whenever we know that some part of it will certainly play no role in answering a query or whenever we know at which point it is most economical to start looking for an answer. Yet this indexing has more to do with database technologies than with the specific nature of linguistic knowledge. An investigation can be launched to reveal the relevant aspects of a type resolution algorithm that could play a role in modelling psycholinguistic effects in the course of processing. This includes the theoretical investigations on how incremental parsing can be simulated in the algorithm (see Future prospects). Lazy evaluation We found that in such a homogeneous architecture one cannot very easily find the way to block the calculation of irrelevant but still associated information, for a given input. A remedy to this has been evolved which blocks the resolution of types that do not contain information potentially contradicting the hypothesis processed. This notion of potential contradiction can be given a formal definition and implemented in the processing algorithm, it can influence type resolution procedure, rendering it lazy in the general case. The implementation of the whole framework involved a considerable amount of programming work to implement the processes for the handling of such databases. Once the system has been implemented we could turn to problems relating to it. On the more practical side we had results relating to the representation of certain fragments of grammar (Rebrus and Trón 2000, Rádai 2000), the automatic acquisition of such networks (Oravecz 2000). On the theoretical side we have investigated what consequences the above approach has on our view of the modularity of mental grammars - since we consider the above system to be a psychologically plausible implementation of the linguistic knowledge of speakers of Natural Languages. Implementing Grammars Once we had a working version of GIN available we started to investigate concrete implementational issues. Papers discuss in what ways results of existing frameworks can be reformulated and integrated in this conception of grammar. This work resulted in descriptions of various phenomena of English and Hungarian. This comprises the following topics: 1. As we pointed out earlier our work has been mainly motivated by the conception of grammar embodied in Construction Grammars. Specific analyses of linguistic phenomena presented in this framework, however intuitive and appealing, failed to attain the degree of exactness required for a direct encoding. Rádai (2000) provides a correct reformulation of the framework in GIN which establishes the way to the computational implementation of CGs.
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Detailed dummary of the results of the reserach
2. Kálmán and Trón (1999a) show that agreement phenomena can not be adequately captured in existing constraint-based formalisms. They claim that a remedy for this can be provided if one adopts the relational hierarchy (GIN) as a grammatical framework. They argue that an analysis advocating the direct encoding of grammatical congruence relations such as agreement can capture a great deal of phenomena more adequately than previous ones. 3. Kálmán and Trón (1999b) show that the strange behaviour of some verbal prefixes in Hungarian verbs which defy an elegant solution in traditional frameworks, argues for relational hierarchy. It is argued that a lexicalist theory implemented in relational inheritance networks is much superior to previous ones in being able to cope with the range of related phenomena. 4. Rebrus and Trón (2000) advocates a novel approach that integrates current trends in declarative phonology with the lexicalist grammatical framework of Construction Grammars. It is showed how the elegant treatments of CV phonology can be encoded in inheritance construction networks. The restricted and universal phonological constructions and the abstract representation of the former together with a conception of hierarchical lexicon provided by the latter offers a promising perspective in the explanation of a wide range of morphologically (and lexically) motivated phonological phenomena. Automatic Acquisition and Lexical Databases An important challenge for a plausible GIN implementation that encodes large fragments of natural language phenomena is to apply some machine learning technique on large amounts of annotated corpora to automatically extract information and build working GIN fragments out of them. As a by-product of this procedure a statistical extension to GIN could be worked out for the modelling of lexical processing with GIN type-resolution. However, to make the automatic induction of such information and the construction of large-scale computational lexicons feasible one needs significant amount of language corpora annotated at least at the morphosyntactic level. This need has led to the fact that considerable work has been devoted within the context of the COMPLIN project to the development of such an annotated database. This work has revealed several technical as well as theoretical problems specific to Hungarian, which problems do not normally arise if the same task is taken for western languages, for most of which the construction of such a database has long been considered a solved issue. Details of the problems encountered and solutions proposed are discussed in Váradi and Oravecz (1999), and Oravecz et. al. (2000).
Non-Complin References in Section 10. Bartos, Huba. To appear. „VP-ellipsis and Verbal Inflection in Hungarian”. Acta Linguistica Hungarica. Dienes, Péter. in prep. VC Phonology. MA thesis, Eötvös Loránd University. Dienes, Péter and Péter Szigetvári. 1999. Repartitioning the skeleton: VC Phonology. Ms., Eötvös Loránd University. Dowty, David. 1979. Word meaning and Montague Grammar. The Semantics of Verbs and Times in Generative Semantics and in Montague's PTQ. Reidel: Dordrecht. Ch.J. Fillmore and P. Kay. 1993.Construction Grammar Coursebook. Reading materials for Linguistics X20, University of California, Berkeley CA. A.E. Goldberg. 1995. Constructions: A Construction Grammar Approach to Argument Structure. The University of Chicago Press, Chicago. Halle, M. and A. Marantz 1993. Distributed Morphology and the Pieces of Inflection. In: Hale, K. and S. J. Keyser (eds.) The View from Building 20: Essays in Honor of Sylvain Bromberger. The MIT Press, Cambridge, MA: 111-176 Ray Jackendoff. 1997. The architecture of the language faculty. Linguistic Inquiry monographs. MIT Press, 1997.
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Itô, Junko and Armin R. Mester. 1995. „Japanese phonology”. In John A. Goldsmith (ed.). The handbook of phonological theory. Cambridge, Mass. & Oxford: Blackwell. 817-838. Kratzer, Angelika, 1994. The event argument and the semantics of Voice. ms. University of Massachusetts at Amhurst. Krifka, Manfred. 1989. Nominal Reference, Temporal Constitution and Quantification in Event Semantics. In R Bartsch, J. van Bethem, and P. van Emde Boas (eds.) Semantics and Contextual Expression. Foris Dordrecht, 75-115. Lowenstamm, Jean. 1996. „CV as the only syllable type”. Ms., Université Paris 7. Appeared in Jacques Durand and Bernard Laks (eds.). Current Trends in Phonology: Models and Methods. European Studies Research Institute, University of Salford Publications. 419-442. Academy of Sciences. Csaba Oravecz and Tamás Váradi. 1999. „Morphosyntactic ambiguity and tagset design for Hungarian”. in Proceedings of the Workshop on Linguistically Interpreted Corpora, EACL'99, pp. 8-13. Association for Computational Linguistics Philip, William (1995), Event Quantification in the Acquisition of Universal Quantification. Doctoral dissertation, University of Massachusetts at Amherst. Rebrus, Péter. in press. „Morfofonológiai jelenségek". In Kiefer Ferenc (ed.) Strukturális magyar nyelvtan 3. Morfológia. Budapest: Akadémiai Kiadó. Ségéral, Philippe and Tobias Scheer. 1999. The Coda mirror. Ms., Université de Paris 7 and Université de Nice. Szigetvári, Péter. 1999. VC Phonology: a theory of consonant lenition and phonotactics. PhD dissertation, Eötvös Loránd University Vendler, Zeno. 1967. Verbs and Times. Linguistics in Philosophy, 97-121. Ithaca: Cornell University Press. Verkuyl, Henk. 1989. Aspectual Classes and Aspectual Composition. Linguistics and Philosophy 12, 39-95. Verkuyl, Henk (1993) A Theory of Aspectuality. Cambridge: Cambridge University Press. Wilder, Chris (1997) Some Properties of Ellipsis in Coordination, in: A. Alexiadou-T. Hall (eds): Studies on Universal Grammar and Typological variation, J. Benjamins, 59-107.
Closed class lexical items in sentence processing
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Closed class lexical items in sentence processing A neurolinguistic approach Zoltán Bánréti
Abstract Non-fluent agrammatic aphasics were tested. The impaired mental parser protects some of the processed syntactic information during first-pass parse and a working memory deficit restricts further processing operations. Closed class elements provide a syntactic frame. Open class items are inserted into the syntactic frame in the course of sentence processing. In non-fluent aphasia the syntactic parser is too slow in processing closed class lexical items, so lexical information in the working memory is already gone when needed. According to the results of sentence repetition tests and grammaticality judgement tests the subjects are unable to integrate the output of the syntactic parser with the fully specified segments of the lexical process. The distribution of patients’ performance in tests reflects the limitations on the interface between the impaired parser and the complexity of the grammatical representation containing a hierarchy of categories and features. 1.1. According to Chomsky (1997), the faculty of language is embedded within the broader architecture of the mind/brain. It interacts with other systems, which impose conditions that language must satisfy if it is to be usable at all. We might think of these as “legibility conditions“. The systems within which the language faculty is embedded must be able to “read“ the expressions of the language and use them as “instructions“ for thought and action. The sensorimotor systems have to be able to read the instructions having to do with sound. The articulatory and perceptual apparatus have specific design that enables them to interpret certain properties, not others. These systems thus impose legibility conditions on the generative processes of the faculty of language, which must provide expressions with the proper “phonetic representation.“ The same is true of conceptual and other systems that make use of the resources of the faculty of language. They have their intrinsic properties, which require that the expressions generated by the language have certain kinds of semantic representations, not others. (Chomsky, 1997. 12-14). 1.2. Brain/mind functions to externalize language will be called human language processor. This paper presents some empirical evidence on relations between grammar and the human language processor. The evidence is based on results of sentence repetition tests performed by Broca’s aphasics. 2. Natural languages tend to contain two quite different sorts of morphemes, those that are primarily of the world (open class items: nouns, adjectives, adverbs with their own lexical-semantic content) and those that are primarily of the grammar (closed class items). The closed class is generally taken to include case endings, prepositions, determiners, pronouns, conjunctions, auxiliaries, inflectional affixes and a variety of other expressions. (cf. Biassou- Tyler- Nespoulous- DordainHarris 1997). Linguistic symptoms of Broca's aphasia are sometimes defined as the impairment of access to closed class morphemes. (Linebarger 1995). The fragmentation or agrammaticality of spontaneous speech, poor sentence repeating skills and good sentence comprehension skills may be correlated with this fact. Closed class morphemes are the elements of a structure-analysing and structure-building complex in on-line speech comprehension and production (Bock 1989). Closed class morphemes can be used as indicators for the speaker since these formatives mark the beginning and the end of noun phrases and other phrases, the units of constituent structure, boundaries of main and subordinate clauses, word order, etc. They impose structure on strings of words. These morphemes are members of computational vocabulary. Accessing closed-class morphemes influences access to open-class words (words that refer to entities in the world) as well. Formatives can radically reduce search time in open class vocabulary, if
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Closed class lexical items in sentence processing
formal information is available as to whether one has to search for a noun, an adverb or an adjective, for example. Speakers access open class words and closed class morphemes by two distinct access systems. The two access systems have to interact, especially during on-line sentence comprehension. (Martin-Saffran 1997). From the point of view of the mental lexicon, there is a level at which theta assigning predicates, like verbs, are members of the computational vocabulary (Frazier-McNamara, 1995). Verbs and their subcategorizational frames, which include surface case endings constitute complex lexical entries. Surface case endings are parts of subcategorizational frames of verbs and mark theta role assigned by the verb on the complements. 3. The interaction of open and closed class lexical items in sentence processing is important for Hungarian speaking agrammatic Broca’s aphasics. In case of Hungarian the inflectional endings, especially surface case ending frames subcategorized for by verbs (predicates) provide an automatic complex device for processing surface sentence structure. There are a number of competing theories of agrammatic aphasia, which appear to cluster around two fundamental hypotheses. One popular assumption is that although in essence the grammar in aphasia is intact, one module of it or other is impaired, some specific rules of the grammar are disappeared. The alternative group can be characterised as the capacity limitation approach. The fundamental claim here is that patient's grammar is wholly preserved, and the deficiency lies in some aspect of the performance system. We refer to the first type of theories as grammar based theory, and to the second type of theories as capacity limitation theory. 3.1. According to the grammar-based theories, although in essence the grammar in aphasia is intact, one aspect of it or other is deficient, which is the source of breakdown of patients' quality of performance. There is no absolute loss of competence, what we face is a disappearance or impairment of some specific rules or principles of the grammar. In the framework of the Minimalist Program (Chomksy 1997), the verb (and the nominal constituents) is already inflected for agreement and tense in the stage of the sentence derivation, where the lexical insertion into the phrase markers takes place. (The agreement and tense features of the verb have to be checked in the different functional nodes. It is the checking of the feature that triggers the verb movement into the functional nodes.) The features are realised as inflectional suffixes/affixes in the Phonetic Form. Thus any substitution of the number/person marker of the subject and the tense inflectional marker of the verb in the Phonetic Form can be interpreted as the changing of the number/person features of the subject, and the tense feature of the verb in the Surface Structure. 3.1.2. An interesting example for grammar based theory is the "Pruning Tree“ Hypothesis. Friedman and Grodzinsky (1995) found tense and agreement errors in the sentence production of the agrammatic aphasic patients in Hebrew. They employ the Split inflection theory elaborated by Pollock (1989) and the Checking Theory of the Minimalist Program to explain these errors. Friedmann and Grodzinsky suppose that the functional categories C, T and AgrP are underspecified in agrammatism and that an underspecified node cannot be projected. Moreover, functional nodes might be selectively impaired in agrammatism. According to their " Pruning Tree“ Hypothesis, the impairment of a lower functional node implicates the impairment of the higher functional nodes in the syntactic tree of a sentence. (Impairment of the functional node Agreement implicates the impairment of Tense phrase and CompP nodes in Hebrew). The feature checking is not carried out in an impaired functional node in the higher functional nodes. 3.1.3. Hungarian is “problematic“ language for this hypothesis. For instance, the Pruning-tree Hypothesis (PTH) makes different predictions in connection with two types of the ungrammatical answers produced by a Hungarian agrammatic patient in sentence repetition tests (Mészáros, 1999). The PTH makes a good prediction of the responses containing only agreement (1). It assumes that
Closed class lexical items in sentence processing
26
only AgrSP functional node is impaired but TenseP is intact. Fig 1. shows the postulated syntactic structure of the answer (1). (1) E: A fiú
a könyveket
nézte,
a lányok
pedig
a hirdetéseket
the boy-NOMsg. the books-pl-ACC lookPASTsg.3. the girls-pl.-NOM however advertisements-pl.ACC It is the books that the boy was looking at, and it is the advertisement that the girls were.
P:* A fiúk
a könyveket
nézte,
a lányok
pedig
a hirdetéseket.
the boys-PL.-NOM the books-pl-ACC look-PAST -SG.3, the girls-pl-NOM however the advertisements-pl.-ACC *It is the books that the boys looks at, and it is the advertisements that the girls
*[a fiúk k [a könyveket j [ a hirdetéseket [........ ] Top
FocP
F
[nézte i [ t j AgrS
ti [
ti
[ tj
ti
[ ti tj tk ]]]]] [a lányok ][ pedig]
TenseP AgrOP VP
TopP
Foc
F’
Postulated syntactic tree of the answer by the patient Fig.1 shows: the checking of the number (and person) feature of the subject failed to come because of impaired AgrSP. At the same time the tense feature of the verb is checked. A functional node above an impaired functional node is not accessible. In (2) agreement functional node is intact resulting in correctly inflected verb for person and number. The agreement inflection is preserved but the tense inflection is not. The answers contain only tense errors. (2) E: Tegnap Ákos fogják.
szidta meg
Marit,
ma
pedig
a gyerekek
yesterday Ákos-NOM sg. scolded-PASTsg3. Mary-ACC., today however the childrenNOMpl3. will-pl3. 'It is John who scolded Mary yesterday, and it is the children who will do so today'.
P:*Tegnap Ákosék
fogják
szidni Marit, holnap
pedig
a gyerekek fogják.
*Yesterday Ákos-pl-NOM will-pl.3. scold Mary tomorrow, however, the children will do so
In accordance with PTH we can assume that the incorrect tense affixation results from the impaired tense functional node. (The tense marker is not omitted, only substituted for another one.) The response (2) is inconsistent with the "Pruning tree hypothesis". The impaired Tense node is lower than the intact Agreement functional node in the syntactic tree. The verb cannot skip over an impaired functional node; that is, the impairment of the TenseP node implicates the impairment of the agreement node. As it can be seen, the Pruning-tree hypothesis makes a wrong prediction to these answers. We presume that this theory alone cannot provide a satisfactory explanation for the answers
27
Closed class lexical items in sentence processing
containing tense agreement error but not agreement error. Moreover it cannot account for the fact that the occurrence of the agreement or tense error is more frequent when the subject or the adverb of time is topicalised but not focused. According to Mészáros (1999) the errors mentioned above can be interpreted as a consequence of the two different operations, first one is used in the reconstruction of the predicate part of the sentence containing focused constituents of the sentence and the second one is used in attachment of topic constituent to the predicate part. The patient is able to reactivate the VP in the antecedent-containing clause. It means that he is able to interpret the semantic and syntactic features in the place of the gap. Mészáros (1999) claims that the reconstruction of the gap has precedence in the course of the construction of the answer. The low performance in the recalling of the sentences supposes that the reconstruction of the VP ellipsis overloads the sentence processor resulting in agrammatical production.
A time-based parser 3.2. We will argue for a different theory that can be characterised as the capacity limitation theory, or the time based approach. The fundamental claim here is that patient's grammar is wholly preserved, and the deficiency lies in some aspect of the mental system. 3.2.1. We take notion of parser as a kind of automatic memory function that becomes specialized in processing of categories and features, involved in grammatical representation of sentences. The parser is a device that transfers information between grammatical representation and message level representation. At the message level the "what-is-to-be-said" is represented. The parser as a whole is adapted to its limited capacity. According to Kolk (1995) paper, complex message structures in working memory are "fine-tuned" to creative linguistic competence. This fine-tuning is related to the size of temporal window produced by parser for syntactic computation and syntactolexical integration during a given time period). The parser based on activation and synchronization functions. Grammatical representation of a sentence is derived from the model of grammar as the output of grammar. This representation contains a hierarchy of relevant grammatical categories and features of sentence. Parser computes the hierarchy of categories and features involved in grammatical representations and transforms them into message level representation. This requires an interaction between parser and grammatical representation of sentence. 3.2.2. Impairments of the syntactic parser appear to include the slowing down of critical functions. According to Haarman and Kolk (1994), Broca's aphasia affects sentence processing by either slowing down the rate at which new elements are constructed or increasing the rate at which they decay. But not both at the same time. Kolk (1995) argues for computational simultaneity or synchrony. His computational model, SYNCHRON, simulates the temporal course of building up a sentence structure representation. Simultaneity or synchrony is associated with bottom-up features. Two critical parameters are involved. In the "slow activation" case, it takes longer for the parser to begin processing of an item. The critical activation level is reached too late, thus the item does not become available for further processing tasks. On the other hand, "Fast decay makes elements unavailable when they fall below their critical level too soon to be combined with other elements..." (284). Cornell (1995) introduced a new computational model, GENCHRON, based on Haarman and Kolk's model. GENCHRON produces semantic representations in accordance with the double dependence hypothesis (Mauner et al. 1993). The grammar used by GENCHRON is a constraint based phrase structure grammar in which rules combine both syntactic and semantic constraints. Cornell's computational model is bottom-up, parallel, and it has the property of simultaneity. The Extended Simultaneity Condition is the following: "Construct a superordinate constituent node, and solve its associated constraints, only if there is a point in time at which all of its subordinate constituent nodes are simultaneously available in memory" (306).
Closed class lexical items in sentence processing
28
In addition to a component of grammar, GENCHRON system has parameter files to control the rate at which nodes become available in memory and with which they decay away. According to Cornell (1995) retrieval time models represent the following deficit: lengthening the time period that it takes to process a new element "increases the likelihood that earlier arriving constituents will have faded from working memory by the time the later arriving constituents are finally constructed" (316). In processing simulation, however, Cornell used a memory time model. This refers to the period during which an element is available in working memory. "Shortening this time period increases the likelihood that earlier arriving constituents will have faded from working memory before later arriving constituents are made available." (Cornell 1995:316) In processing simulation memory-time parameters were varied according to the openclass/closed class distinction. Cornell made the following parameter settings: Open-class items persist for: 6 clock cycles; Closed-class items persist for: 3 clock cycles; Retrieval time for all items: 1 clock cycle. (Cornell 1995:317.) 3.2.3. Differences between memory time for open-class and closed class items are important. According to the parameter settings above, closed-class items fade away so fast from memory that the construction of a proper NP (for instance) is doubtful. Cornell supposes that a processing account of asyntactic comprehension should make predictions for correct/incorrect grammaticality judgements as well. He suggests as a next step that "The version of GENCHRON used in these simulations is subject to the extended simultaneity condition: it waits until all subtrees have been parsed and then attempts to solve all of the constraint at once. Generalized Simultaneity Condition: The output of a particular task only becomes available when and if the output of all of its subtasks is available at some point in time. At that point in time the superordinate task begins to make its output available" (323). 3.2.4. To access a closed class item is to retrieve the structure building operations that are associated with that closed class item. The case ending frame assigned by the category of the verb and other inflectional endings open up a syntactic slot for integration with a content word filler. Impairments on access system of closed class items cause a delay in opening up syntactic slots. In the sense of Kolk (1995), this means that the point in time at which closed class morphemes deliver a syntactic slot for an open class lexical filler is in synchrony with the late phase of lexical selection, at the end of activation of a content word, when "the amount of activation is relatively low, competition from alternative lexical candidates is relatively high" (Kolk 1995, 290.). 4. Sentence repetition test In the course of a sentence repetition test the patient gave answers that were suggestive of structure building operations of the mental parser. We will demonstrate this below. The patient was 37 years of age, right handed, a car mechanic, suffering from a stroke, which resulted in extended fronto-parietal hypodensity in left hemisphere. He performed some repetition tests. (E stands for the examiner who utters the sentence to be repeated. P stands for the patient's replies. The test was in Hungarian; the glosses below contain the relevant details only):
Closed class lexical items in sentence processing
29
(3) E: Péter
beszélgetett
Marival.
Peter-nom talk-3sg/past Mary-with 'Peter talked to Mary'.
P: Péterrel beszél
..iinná ........
-val
Peter-with talk-3sg/present..nonsense-word -with
(4) E: Marival
találkozott
János.
Mary-with meet-3sg/past John-nom 'John met Mary'
P: Marival.... beszélgetett
volna
vele.
Mary-with talk -3sg/past would have her-with
Ő beszélgetett
vele....... Marival.
He talk-3sg/past
her-with... Mary-with.
(5) E: Mari
megcsinálta
az ágyat
és lefeküdt.
Mary-nom make-3sg/past/def the bed-acc and (she) go-3sg/past to bed. ‘Mary made the bed and (she) went to the bed.‘
Alex send-3.sg/past a postcard-acc Mary-dat. 'Alex sent Mary a postcard.'
P: Sándor jött Alex
és akkor írta‚
és
azt...
azt
come-3sg/past and then write-3sg/past/def and that-acc that-acc
Closed class lexical items in sentence processing
30
akkor ment
hozta....
a .. mi az
a....mit??
then go-3sg/past bring-3sg/past/def the what is that what-acc?
E: Képeslap! Postcard-nom!
P: Épetlapot,
épeslapot
édeslapot.
Nonsense word-acc nonsense word-acc sweetcard-acc
E: Mit csinált
vele?
What did he do with it?
P: Képeslapot adott
a kis gyereknek
adott oda
Postcard-acc give-3sg/past the little child-dat give-3sg/past to ‘He gave a postcard to the little child...gave to and'
... és akkor ment haza ... and then go-3sg/past home ...'and then he went home'.
Analysis of the repetition test 4.1. In principle, the task of repeating someone else's words could be accomplished in several ways: (i) Purely phonological repetition: no syntactic or semantic processing is performed; the subject simply repeats what he/she hears. (ii) Surface syntactic repetition: the input sentence is processed up to the level of surface syntactic form, which is then repeated without any semantic processing. This requires the subject to process the surface syntactic structure, derive a phonological representation, and then produce the phonological form thus derived. (iii) Unmonitored semantic repetition: the input sentence is processed to extract the semantic gist; the subject then repeats that gist without endeavouring to use the same syntactic structures or phonological forms. (iv) Monitored repetition: the patient processes the sentence both syntactically and semantically, then attempts to produce an utterance, which matches the phonological, syntactic, and semantic properties of the original utterance. Our patient was pursuing the strategy of monitored repetition (iv). 4.2. Temporal asynchrony between accessing case endings and content NPs is shown in example (3). The examiner produced an utterance in which the first NP was marked for nominative
31
Closed class lexical items in sentence processing
with a zero suffix (Péter) and the second NP was marked with instrumental case ending (Mari+val, Mary-with) in sentence-final position. The patient produced an utterance in which the first NP was marked with instrumental case ending (Péter-rel, Peter-with) and the final NP was not mentioned at all. That is to say, the patient attached the case ending of the final NP to the first NP. He retrieved a case ending that was heard later and attached it to a NP that was heard earlier. In example (4) the target sentence contained a sentence-initial NP marked with instrumental case ending (Mari-val, Mary-with) and a final NP marked for nominative with a zero suffix (János, John-nom). In his first attempt, the patient repeated the sentence-initial NP marked with instrumental case (Mari-val). He was unable to retrieve the sentence-final NP marked for nominative case with a zero suffix (János, John-nom) rather he produced a grammatical pronoun marked with instrumental case, i.e., he attached the instrumental case ending that has been retrieved to the pronoun (vel-e, withher). In his second attempt, the patient was able to retrieve the first case ending without the content NP: he produced a grammatical pronoun marked for nominative case with a zero suffix (Ő, He-nom) then produced a grammatical pronoun marked with instrumental case ending (vel-e, with-her) and finally, after a pause, he repeated the content NP marked with instrumental case ending (Mari-val, Mary-with). To sum up: by the end of the second attempt, the patient produced the complete surface case ending frame of the target verb (NP-nominative, NP-instrumental), he tried to attach case endings to NPs, during this process he used grammatical pronouns (marked for nominative and instrumental case as well). He was able to attach a case ending that was heard earlier to a NP that was heard earlier. He was able to retrieve a case ending that was heard later and was unable to attach it to a NP that was heard later. In our repetition test the parsing mechanism could not proceed unless a verb was produced. This is shown in example (5). The target utterance contained two conjoined verbs with their different case frames. The patient was not able to retrieve either of the verbs and was even unable to "list" only the nouns with correct case endings. He also failed to use any inflections (see example (5)). But he never made both inflectional errors and errors in the choice of the main verb in the same sentence. This is compatible with the assumption that the patient has to trade processing of surface form against lexical access. (Inflection is part of the surface parser module but I do not claim that this (sub)module would not be impaired). In example (6), the patient was attempting to repeat the Hungarian equivalent of Alex sent Mary a postcard. He made several false starts: notably, they were semantically related to the intended message. First, he tried the Hungarian equivalent of the verb came (semantically a motion verb, like sent, but intransitive). Next he tried the Hungarian equivalent of the verb write-3sg/past/def (with 3.pers.-suffix referring to direct object as well), correctly transitive but more closely related semantically to postcard than to sent). However he was not able to retrieve postcard itself. He mentioned the accusative case ending (-t) of postcard without the content word (postcard), and linked the accusative case ending to pronouns. (az-t: that-acc, mi-t: what-acc.) Next he tried the Hungarian equivalent of went (which is again, incorrectly, intransitive). Next he came up with the Hungarian equivalent of bring3sg/past/def (with 3.pers-suffix referring to direct object) which is both syntactically and semantically close to sent. But by that time he was completely unable to retrieve what the object was supposed to be. Next he heard the original noun marked for nominative with a zero suffix (the Hungarian equivalent of postcard-nom) and he returned a nonsense word marked with an accusative case ending! Next he heard a Hungarian pronoun marked with instrumental case ending (What did he do with-it ?) and again he returned an accusative case ending but by that time he was able to repeat the original content word (postcard-acc) linking accusative case ending to this content word. Hungarian has a very rich inflectional system for nouns. It is remarkable that the patient did not make purely inflectional errors in the repetition task. If he approximated the class of the target verb, then its surface case frame was retrievable. Utterances in (6) show that the surface case ending of a noun was mentioned earlier than the noun itself (with that case ending). See in (6) for instance the
Closed class lexical items in sentence processing
32
temporal relation between the Hungarian accusative case ending and the Hungarian equivalent of postcard, and the temporal relation between the Hungarian dative case ending and the Hungarian equivalent of Mary/little child, nouns in the dative in the patient's responses. It is remarkable that the patient did not make purely inflectional errors during repetition task. If he approximated the class of target verb, then its surface case frame was retrievable. The patient's responses exhibit the features of temporal desynchronization. Restarting, however, improves patient’s performance and repairs desynchronization in repetitions. 4.3. Restarting Our patient restarted his responses many times. Restarting can improve aphasics' performance and repair desynchronization. The normal speaker, after error identification, can simply restart the production of the sentence, or part of it. Restarting automatically leads to repairing. In the aphasic speaker the situation is different. The question is how can restart lead to improvement. Suppose the critical limitation would consist in a reduction of the size of a syntactic buffer. If a particular structure would be too complex for this small buffer, restarting would have no benefit: a structure of given complexity that does not fit into the buffer will never fit. When the limitation is a temporal one, the situation is different. The basic difficulty that results from a timing deficit is the following. Particular representational elements are activated too slowly, and reach their active memory phase in working memory too late, when other elements, with which they have to be in synchrony, are already gone out of working memory. No possibilities for synchronization. But restarting does offer an advantage. After decay, the critical elements may still have a relatively high level of activation, because of the fact that they have just been activated. Reactivation can occur from this higher level, rather than from the rest level, and the critical element will reach the active memory phase sooner. In this way, restarting leads to faster processing and to the possibility of synchronization of structure building elements in working memory. 5. Grammaticality judgements Agrammatic Broca's aphasics can correctly judge the grammaticality of certain sentences (Linebarger 1995), while they are unable to produce them correctly. This has been interpreted in various ways. We present some samples of Hungarian data that support a time-based approach to sentence processing. Hungarian is a more or less free phrase-order language. (Bánréti, 1994, É.Kiss-Kiefer,1994, Pléh 1998). Syntactic functions and/or thematic roles are expressed by attaching case suffixes to NPs. The possible subcategorization by verbs involves at least 17 cases expressed by surface case ending forms. Suffixes of a finite verb express number and person of subject and definiteness of direct object. Another set of suffixes indicates tense and mood. 5.1. The partial process The grammaticality judgement tasks do not involve the kind of extended simultaneity. These tasks are easier than comprehension tasks in aphasia. Grammaticality judgements require shorter availability of the syntactic representation in memory than comprehension tasks and are therefore less easily disrupted. Solving judgement tasks does not require that the parser waits "until all subtrees have been parsed and attempts to solve all of the constraint at once". It is not necessary that a syntactic tree for a full sentence should be available. Judgement of grammaticality is possible as soon as minimally sufficient structural information has been made available. Patients' performance in judgements depends on the type of grammatical error hidden in the task, i.e., on the availability of the minimally sufficient structural information, which is necessary for correct judgement. 5.2. The initial structure building operations In what follows we apply the first-pass parse hypothesis. The hypothesis of initial structure building operations has been proposed by a number of psycholinguists (e.g., Linebarger 1990). In accordance with this hypothesis I assume that in the case of grammaticality judgements an initial
Closed class lexical items in sentence processing
33
structural analysis is computed and is subsequently interpreted. This is followed by later processing operations involving constraints on the indexing of structures. In the sense of Saffran (1985), the firstpass parser protects some of the processed syntactic information during first-pass parse and a working memory deficit restricts further processing operations. The solution of a grammaticality judgement task is based on a minimally sufficient structural representation. (For aphasic subjects, grammaticality judgement tasks are easier than comprehension tasks). What counts as a minimally sufficient structure, within a given language, will change from task to task. 'Easy-to-judge task' means that minimally sufficient structure is available and 'hard-tojudge task' means that minimally sufficient structure is not available. As for Hungarian speaking aphasics, we assume that the first-pass parser is based on the verb, its subcategorizational selections for syntactic category of complements and for case endings (that marks theta role on surface structure). This constitutes important syntactic information for the possible syntactic structure, the possible linear order of categorized syntactic slots and the hierarchy of nodes of the structure. According to the Projection Principle, syntactic representation must be projected from the lexicon in that they observe subcategorizational properties of lexical items. 5.3. Subjects Five subjects had had a cerebral vascular accident (CVA) in the left hemisphere. Patients were diagnosed as agrammatic Broca's aphasics on the basis of performance profiles on the Western Aphasia Battery (WAB) (Kertesz 1982) and in further clinical evaluations by speech-language pathologists and neurologists. All subjects were right handed. Patients were required to judge taperecorded sentences. The instruction was "please tell me whether this sentence is correct or incorrect" „As you feel, and no explanation is required“. Grammatical and ungrammatical items all figured in minimal pairs in the test. Each minimal pair stood for a particular structural category. Members of a minimal pair were separated by intervening items. 5.4. The main experimental results Some conditions were easy and some hard. The hard conditions break into two main groups: systematic misjudgements and guessing. Table 1 shows the distribution of judgements according to particular sentence structures.
5.4.1. Examples for easy tasks In easy conditions patients’ judgements were correct for grammatical and ungrammatical sentences, alike. Case endings in the sentence: The acceptable version contains a grammatical configuration of surface case endings assigned by Verb to its arguments, and agreement of verbal suffixes expressing person and number of Subject and Object. The ungrammatical versions involved errors with surface case endings attached to NPs and errors with person-number suffixes of a finite Verb. In these items only one argument NP preceded the verb, the others followed it in the surface string. Examples: (7) a. A papá-nak
kölcsönadott
a fiú
egy könyv-et .
the father-dat lend- past/3sg the boy-nom a book-acc 'The boy lent a book to the father.'
b. * A papá-*ra
kölcsönadott a fiú
egy könyv-et .
the father-*on lend-past/3sg the boy-nom a book-acc
(8) a. Róbert
nézi
a könyvet.
Robert-nom look-3.sg/present/def the book-acc 'Robert looks at the book'
b. * Te
nézi
a könyvet.
You-nom look-3.sg/present/def the book-acc
(9) a. A gyerek-et
elküld-te
a bolt-ba
a mama.
the child-acc send-past/3sg the shop-to the mother-nom 'The mother sent the child to the shop.'
b. * A gyerek
elküld-te
a bolt-ba
a mama.
the child-nom send-past/3sg the shop-to the mother-nom
V-anaphora: copying only bare V Another example for easy conditions is task V-anaphora, which requires the judgement of the category of Verb itself, whether it is an attribute predicate or an action verb. Example:
Closed class lexical items in sentence processing
36
(10) a. János magas volt és Mari is. John tall
was and Mary too
'John was tall and Mary too.'
b. * János magas volt és John tall
ezt
csinálta Mari is.
was and this-acc did
Mary too
*'John was tall and so did Mary.' 5.4.2. Examples for systematic misjudgements The hard conditions break into two main groups. The first one is the group of systematic misjudgements. In this case, acceptable sentences were judged as good with 100%, but unacceptable counterparts were judged as good with close to 100%. These tasks contain errors, which cannot be detected by means of surface case frame of the verb. Unfocussable sentence adverbial in focus: In these tasks the surface case ending frame is the same in the grammatical and ungrammatical sentences, alike. In Hungarian there is a distinct syntactic position for the focused constituent, accompanied by heavy stress, before the Verb. Perhaps-type sentence adverbial can occur in several syntactic positions, except the position of focus. Perhaps-type adverbial is an unfocussable category in Hungarian syntax. If this adverbial is put into syntactic position of focus, the sentence will be ungrammatical. Patients, however, accepted this unfocussable category in the position of focus. Example: Perhaps-type of unfocussable adverbial is put into the syntactic position of Hungarian focus in front of the verb. Capitals and " stand for the focus position and heavy stress. (11) a. János talán
elkésett.
'John perhaps came late.'
b. * János "TALÁN késett el. It is PERHAPS that John came late. All three arguments precede the verb: Other example for systematic misjudgements is task All three arguments precede the verb. This condition involved errors with surface case endings. It is well known: the Verb assigns the surface case frame attached to NPs. Because, in these conditions, verb was the last syntactic constituent in surface string, the correctness of case endings assigned to NP's may be assessed without any knowledge of verb or, once verb becomes known the entire string can be recalled and case endings verified. Under these conditions patients failed to detect errors with surface case endings. Examples: Judgements of case endings and agreement of person and number suffixes between NPs and Verb are required. All three NPs precede the Verb. (12) a. A gyerek-et
a bolt-ba
a mama
elküld-te.
Closed class lexical items in sentence processing
37
the child-acc
the shop-to the mother-nom
send-past/3sg
'The mother sent the child to the shop.'
b. * A gyerekről
a bolt-ba
a mama
elküld-te.
the child-about the shop-to the mother-nom
(13) a. A papá-nak
a fiú
egy könyv-et
the father-dat the boy-nom a book-acc
send-past/3sg
kölcsönadott. lend-past/3sg
'The boy lent a book to the father.'
b. * A papá-*ra
a fiú
egy könyv-et
the father-*on the boy-nom a book-acc
kölcsönadott. lend-past/3sg
5.4.3. Examples for Guessing The second main group of hard conditions is Guessing: Judgements were random or chaotic. With a subtype of these tasks patients were required to judge syntactic dependencies, which involved two clauses, two different verbs and dependencies between arguments of these two verbs (tasks of VP- anaphora, Gapping, Sentential intertwining, pro-Subject). pro-Subject In the example below the Subject is the Hungarian equivalent of my mother. According to the grammatical rules of Hungarian, the overt lexical item of Subject from the first clause can not be repeated in overt form in subject position of the second (subordinate) clause. A phonologically empty pronoun must be found in the position of the repeated Subject (indicated by pro). If this position is filled with the repeated Subject in overt lexical form, the whole sentence becomes ungrammatical. Example: pro is found in the position of repeated Subject. Judgements are required for pro and overt lexical material in the syntactic position of the repeated Subject: (14) a. Anyukám
azt gondolta, hogy
'My mother thought i
megkapta az állást.
that [pro] had got the job.' i
b. * Anyukám azt gondolta, hogy Anyukám * 'My mother i
megkapta az állást.
thought that my mother had got the job.' i
Closed class lexical items in sentence processing
38
Aspect A different example for type Guessing is task Aspect. In the grammatical version of example below, the verb in itself denotes progressive aspect. This is compatible with the ‘duration’ meaning of a time adverbial in the sentence (Hungarian equivalent of for two days). The ungrammatical version contains a verbal prefix that has [perfective] feature, indicating perfective aspect. This verbal prefix is Hungarian EL. And there is a time adverbial with duration meaning -- (for two days) -- in the sentence, again. [Perfective] feature and [duration] feature are incompatible with each other, therefore the sentence will be ungrammatical. Patients failed to detect this feature clash. Example: Judgements are required for compatibility of aspect of verb and time adverbial. (15) a. Két napon át for two days
készítette
az ebédet.
(she) was making the dinner-acc.
'She was making dinner for two days.'
b. * Két napon át
az ebédet.
elkészítette
for two days (she) has made (='completed making') the dinner-acc
Sentential intertwining: Judgements are required for lexical material in the syntactic position of a trace of moved NP. The constituent THE BOOK was moved from the subordinate clause into the main clause. Its trace is marked by (trace). Capitals and " stand for heavy stress-bearing Focus position) (16) a. Maria KÖNYVET mondta, hogy Mary the book-acc
said
megveszi Jánosnak.
that (she) buys (it) John-dat
'As for Mary, it was the book that she said she would buy (trace) for John.' i
i
b. * Mari a KÖNYVET mondta hogy a kabátot Mary the book-acc said
megveszi Jánosnak.
that the coat-acc (she)buys John-dat.
* 'As for Mary, it was the book that she said she would buy *the coat for John.'
Anaphora + Case: Judgements are required for case assignments to anaphora and its antecedent. Word order is free, the case assignment, however, is bound. Antecedent must be marked with a zero suffix for nominative and anaphora must be marked with accusative case ending. Therefore NP-nom and himself-acc are grammatical but the NP-acc and himself-nom are not grammatical. (17) a. A vezető
látta
önmagá-t
the driver-nom see-past/3sg/def self-3sg/acc 'The driver saw himself in the mirror.'
a tükörben. the mirror-in
Closed class lexical items in sentence processing
39
b. * a vezető-t
önmaga
látta
a tükörben.
the driver-acc self-3sg/nom see-past/3sg/def the mirror-in * 'Himself saw the driver in the mirror'.
5.5. A post-hoc analysis of data How can parser and grammatical representation of a sentence interact with each other? I suppose that patients' performance in judgements depends 1/ on the capacity of the impaired parser, and 2/ on the type of grammatical error hidden in the grammatical representation of sentence. I accept the hypothesis of a distinct first stage of sentence parsing, which is called first-pass parse or initial structure building operations. 5.5.1. Judgements in easy conditions can be based on initial structure building operations and the first-pass parse can protect information that was analysed The first pass parse is supposed to be a more or less phrase structure parse, sensitive only to the basic features of syntactic categories of input. Initial structure building operations process only the scheme or “gestalt“ of sentence. Grammatical errors involved in our easy conditions were related to basic features of syntactic categories. Therefore judgements in easy conditions can be based on dependencies, which are computed during first-pass parse, when initial structure building operations take place. According to easy tasks in our test, the crucial relations are the following: the local dependencies between the category of verb and its subcategorization frame, its surface case ending frame and tense and mood inflections. Processes can be effected in stepwise checks on surface inflectional endings: "what it is seeking to match what in their basic features“. Parser is orientated by sets of structural expectations. These dependencies are carried along as alterations of the internal state of the parser, therefore this information can be protected from temporal or memory deficit provided that first-pass parse works. The specific semantic/pragmatic features are not available to the first pass parse. 5.5.2. Systematic misjudgements can be related to erasure of specific features during processing and to slowing down of parser Some syntactic information, which is not encoded in the internal state of parser, after first pass parse, is unprotected. Unprotected information decays more rapidly in aphasics than in normals. This can cause the erasure of the specific features of syntactic categories (like category of unfocussable adverbial) and the underspecification of features of closed class categories (like case endings). The erasure of specific features of syntactic categories and closed class categories result in an incomplete processing of sentence structure. The grammaticality judgements can be based on partial processing. In systematic misjudgements patients made a partial analysis and were unable to detect the feature clash lurking there, when the critical features were not expressed by surface forms, rather they were “hidden“ into the properties of a syntactic category. (Features of unfocussable sentence adverbial or features of reciprocal anaphora). This can lead to a strong Yes-bias type of poor performance. With task All three arguments precede the verb, grammatical errors were related to the configuration of case endings. Patients' performance, however, deteriorated to Yes-bias. The relevant data for judgements are relations between specific category of verb, which is the last constituent, and a NP, which is the first constituent. The correctness of case ending attached to the first NP can be judged after the verb has processed. In other words, the correct judgement of the first NP requires the Verb and its subcategorization frame as a starting point. When the verb becomes known the entire NP string preceded the verb must be recalled and the case ending attached to first NP can be verified. In this condition patient’s performance reflected the slowing down of the parser: because Verb was in
Closed class lexical items in sentence processing
40
the last position of the surface string, the slow parser was too late to receive its starting point: the category of Verb and its surface case ending frame. The reason why patients neglected the configuration of case endings is the lack of the safe starting point in due time. Patients’ incorrect judgements reflect the fact that NPs, one by one, were correct in themselves, if they were considered independently of Verb. Patients may follow a strategy like this. It is remarkable: patients' performance was 100 % correct in easy tasks Case endings in the sentence at which Verb was not the last but the second constituent in surface string. 5.5.3. Guessing responses reflect a sketchy and unfinished analysis of stimuli because of desynchronization of parsing modules With Guessing conditions, subjects not only failed to detect ungrammatical features of stimulus, but also mysanalyzed fully grammatical sentences. How is it possible? To judge these tasks, syntactic and lexical processes should have been integrated. In compound sentences, patients should have judged whether syntactic positions (like Subject, Hungarian Focus or a position of a trace of moved constituent) and their content word fillers were associated with each other grammatically or were not (tasks pro-Subject, Sentential intertwining). Or, patients should have judged whether features of a closed class item were compatible with features of a content word when they were in distinct syntactic positions (tasks Aspect and Anaphora + case). Impairments on accessibility of closed class morphemes create syntactic difficulties. The results in our grammaticality judgement tests are compatible with findings in Haarmann and Kolk (1994) and Kolk (1995): agrammatic aphasia may show either slow activation or fast decay but not both at the same time. The normal activation goes at the expense of fast decay and, vice versa, normal decay goes at the expense of slow activation. Applying this theory to our data we find the following. Specific features of syntactic subcategories and closed class morphemes can be activated at a normal rate, but then they decay very fast, too early from working memory; or they can be retained at a normal rate, at expense of slow activation into working memory. In the fast decay case other specific lexical information had not been activated yet, when needed. In the slow activation case other specific lexical information in working memory is already gone when needed. The fast decay or slow activation of grammatical features and subfeatures causes a desynchronization in the building of syntactic structure. Syntactic slots are opened up too late or too early for content word filler; specific lexical information in working memory had not been activated yet or is already gone when needed. Therefore patients are not able to complete the analysis of stimuli, processing operations result in a merely sketchy and unfinished structure. Patients were aware of their unfinished analysis; they often made comments on it. This could lead to guessing responses on complex, non-local relations. 5.5.4. Summary Patients were able to use of initial structure building operations involved in first pass parse for correct judgements of easy tasks. In normals first pass parse must be tightly synchronized with a second major parsing module that extracts detailed and specific features of category of arguments and predicate. But fast decay or slow activation of specific, unprotected information in working memory can cause desynchronization between processing modules. The consequences are: systematic misjudgements or guessing responses, depending on the type of grammatical error and the complexity of sentence to be judged. 6. ellipsis and sentence processing 6.1. In our view ellipsis is essentially non-insertion of phonologically based Vocabulary items into the nodes of syntactic structures. From the point of view of syntax-lexicon interface, what used to be referred to as the lexicon is in fact at least two distinct lists of items: one serves as the store of initial syntactic inputs, in the form of syntactic/semantic feature bundles, while the other (called Vocabulary) contains the phonological shapes, to be associated with the featural nodes postsyntactically. Only the semantic-syntactic feature bundles participate in the syntactic computation,
Closed class lexical items in sentence processing
41
and one output of the computation is associated with the elements of the phonologically based Vocabulary. The way ellipsis resolution must be conceived of is likely to support this view of distributed lexicon. A new account for Hungarian ellipsis data in the frame of the distributed lexicon theory is found in Bartos 1998. 6.2. Ellipsis in agrammatic aphasia 6.2.1. According to Kolk- Hofstede 1994, agrammatics overuse linguistic option of ellipsis in free conversation. Telegraphic, fragmented speech shares properties with normal ellipsis, when the missing elements can be derived from the context. Kolk - Hofstede 1994 presented a list of congruent properties of normal ellipsis and agrammatic, fragmented spontaneous speech. The use of elliptic sentences in spontaneous speech is a kind of adaptation. Broca's aphasic patients are aware of their reduced capacity in linguistic system, therefore they employ elliptic constructions. The role of this strategy is to prevent computation overload in the linguistic system. Employment of this strategy (among others) is optional rather than obligatory. 6.2.2. Hungarian word order is free; thus any permutation of subject, verb and object is grammatical. Hungarian is a discourse configurational language: the ordering of constituents has discourse functions. Syntactic positions like topic position and focus position contain key constituents of sentence. These syntactic positions serve to express discourse functions: topic is GIVEN, focus is NEW, CONTRASTED, compared to previous discourse. Topic and focus are not restricted with respect to case. A DP in topic position can be marked with accusative, dative, instrumental case endings. The same is true for a DP in focus position. A sentence can contain more than one DP in topic position and only one DP in focus position. Ellipsis is understood as the non-insertion of the phonological shape of a V’ (or a VP) after focused DP or quantifier DP in a surface syntactic string. Ellipsis does not coincide with VP anaphora. In the case of ellipsis there is NO overt anaphoric expression in the position of elided string (like. …did too). We refer to the elided V -projection (V-bar) as an empty category of V-bar. Hungarian grammar allows forward and backward types of Verb Phrase ellipsis. Some examples: In the examples: [………..] stands for the position of elided string, which is a V-bar (Cf. [ V DP ]. Diagrams contain relevant details only: DP/t = DP in topic position DP/q = quantifier DP (NP)
AdvP = Adverbial Phrase
DP/focus= focused DP (NP)
A = Adjective (Phrase)
V = verb DP-acc, DP-dat, DP-poss:= DP marked for accusative case, or dative case or possessive , respectively. DP-nom= marked with a zero suffix for nominative. pro=pronoun
Hungarian forward ellipsis in co-ordinated sentence:
Forward ellipsis after quantifier position: DP/t DP/q V DP
and DP/t DP/q [ V DP ]:
(18) Mária
" minden fiúnak odaadta az ajándékot,
Mary/nom every
boy-to gave
majd János minden lánynak
the present-ACC, then John/nom every girl-to
[ V DP ].
Closed class lexical items in sentence processing
42
DP/t
DP/q
V
DP
DP/t
[ V DP ].
conj DP/q
'MARY gave the present to EACH BOY, then JOHN to EVERY GIRL’.
Forward ellipsis after DP/focus position: DP/t DP/focus V DP and DP/t DP/focus [ V DP ]: (19) Péter
"Annának mutatta be
Peter
Ann-to
DP/t
DP/focus
Róbertet , Jen pedig “Marinak [ V DP ].
introduced(in) Robert-acc , Eugene, however Mary-to V
DP
DP/t
conj
DP/focus [ V DP ].
'PETER introduced Robert to ANN but EUGENE to MARY.'
Forward Sluicing saves a Wh-word: DP/t DP/focus V DP but DP/t not V that when [ S1 ] (20)
[S2…….………]
Erzsi "London-ban tanult angolul, de
én nem tudom, hogy "mikor [ S1 ].
Liz
I not know
London-in learned English but
DP/t DP/focus
V
DP
conj DP-t neg V
that when comp Wh/focus [ S1 ].
'Liz has learned English in London but I do not know when.'
Hungarian backward ellipsis in co-ordinated sentence: Backward ellipsis after quantifier position: DP/t DP/q [V DP ] and DP/t DP/q V DP (21) Mária
"minden lánynak , [ V DP ], János
Mary/nom every girl-to DP/t
DP/q
pedig
minden fiúnak odaadta az ajándékot.
John/nom whereas every boy-to gave the present-acc [V
DP] DP/t
conj
DP/q
V
DP .
'MARY [gave the present] to EACH GIRL , and JOHN gave the present to EVERY BOY'.
Backward ellipsis after DP/focus position: DP/t DP/focus [V DP] and DP/t DP/focus V DP (22) Péter
'PETER [introduced Robert ]to ANN but EUGENE introduced Robert to MARY.'
Backward Sluicing saves a Wh-word: DP/t not V that when [ S2 ], but DP DP/focus V
DP .
[S2…………..……………..…] (23) Én nem tudom, hogy "mikor [ S2 ] I
not know
DP/t not V
that when
de .Erzsi "London-ban tanult angolul, . but Liz
London-in
comp wh-focus [ S2 ] conj DP/t DP-focus
learned English V
DP
' I do not know when, but Liz has learned English in London.'
6.2.3. Forward VP Ellipsis (FVPE) is dependent on its antecedent. The syntactic tree is complete. Syntactic and semantic features of lexical items are present in ellipsis site; it is the phonological form that is not inserted. No need to assume deletion of lexical items. Backward VP Ellipsis (BVPE) sites result from non-insertion of phonological shapes of lexical forms. In the frame of minimalist program Wilder (1997) adopts “split lexicon“ approach, following Halle & Marantz (1993). According to this approach there are lexical items containing syntactic and semantic features <Syn, Sem>, but lacking phonological content of their over counterparts. The usual structure derivation is fed by lexical items comprising <Syn, Sem>, but lacking . Corresponding phonological features are inserted by a post-S-structure operation of Vocabulary Insertion applying at Spell-Out. Vocabulary Insertion feeds PF but not LF. Wilder (1997) proposes the following. Forward ellipsis sites contain lexical content throughout the derivation, but fail to undergo phonological form-insertion. Backward ellipsis sites result from deletion after form-insertion. Identification asymmetries between forward and backward ellipses fall out as a consequence of the different levels at which identity is checked: forward ellipsis is licensed at Logical Form and backward ellipsis is licensed at Phonetic Form. 6.3. Sentence repetition tests We tested neurolinguistic reality of identification asymmetries with direction of VPE mentioned above. Our subjects were aphasics. They were diagnosed as agrammatic Broca's aphasics having good comprehension skill and a kind of syntactic and phonological (motor) impairment in speech. Their speech output is characterized by difficulties in using inflectional affixes and grammatical formatives, leading to fragmented telegraphic speech, (“syntactic“ impairments) and difficulties in phonological/phonetic output: substitutions, omissions or distortions of sound (“motor“ impairments). 6.3.1. Test material involved co-ordinated sentences with VP ellipsis sites. Each test contained 15 sentences containing forward VP ellipsis and 15 sentences containing backward VP ellipsis. Two subjects were given the test three different times. Sentence patterns were filled with different (though equally frequent) words in each test but we did not change the sentence structures themselves. To repeat sentences patients were pursuing the strategy of monitored repetition involving two basic operations: (1) processing the heard utterances both syntactically and semantically, then storing them; (2) attempting to produce an utterance, which matches the phonological, syntactic, and semantic properties of the original utterance. 6.3.2. The main experimental results:
Closed class lexical items in sentence processing
44
Table 1. - Forward ellipsis Total:
90
Correct responses:
52
Elided V in overt phonological form in the correct responses: 24 Incorrect responses:
38
The main types of the errors in the incorrect responses (One response can contain more than one error) Plural inflection attached to NP:
9
Agreement inflection (number, person) attached to Verb:
12
Tense inflection:
14
Case ending:
15
Second elliptic clause is fragmented:
4
Table 2. - Backward ellipsis Total:
90
Correct responses:
21
Elided V in overt phonological form in the correct responses: 3 Incorrect responses:
69
The main types of the errors in the incorrect responses: (One response can contain more than one error) Plural inflection attached to NP:
14
Agreement inflection (number, person) attached to Verb:
28
Tense inflection:
21
Case ending:
20
First elliptic clause is fragmented:
29
Ungrammatical copy of person-number features of elliptic conjunct into the licensing clause:
12
6.3.3. Examples from the material of the tests: Correct response: (24) E: János a "repülőgéppel érkezett meg Londonba, Mari pedig a "kocsival [ John the plane-by
V PP
arrived perf London-to Mary, however the car-by
' John arrived in London by plane Mary however (arrived in London) by car.'
P: János a repülőgéppel érkezett meg Londonba, és Mari a kocsival [ John the plane-by
arrived perf London-to
V PP
and Mary the car-by
]
]
Closed class lexical items in sentence processing
45
'John arrived in London by plane and Mary (arrived in London) by car.'
The response is grammatical but not identical with the target: (25) E: Mária
minden fiúnak odaadta az ajándékot,
Mary/nom every
boy-to gave
majd János minden lánynak
[ V DP ].
the present-ACC, then John/nom every girl-to
'MARY gave the present to EACH BOY, then JOHN to EVERY GIRL’.
P: Mária
a fiúknak odadta az ajándékot,
Mary/nom the boys-to gave
János
meg a lányoknak.
the present-ACC, John/nom then the girls-to
The response is grammatical. Two constituents of elliptic clause are neglected and elided verb is repeated in overt phonological form: (26) E: Erzsi "London-ban tanult angolul, de én nem tudom, hogy "mikor [ S1 ]. Liz
London-in learned English but
I not know
that when
'Liz has learned English in London but I do not know when.'
P : Erzsi "London-ban tanult angolul, hát... valamikor tanult ott [ S1 ]. Liz
London-in learned English well
once learned there
'Liz has learned English in London well once upon a time. (she) learned there.'
Distribution of case endings is different from the target. The elided verb is repeated in overt phonological form: (27) E: Péter Peter
'Peter introduced Robert to ANN and Eugene to MARY.'
First elliptic clause is fragmented and mixed with the second one. Ungrammatical copy of person-number features of elliptic conjunct into the licensing clause (28) E: Mária
"minden lánynak , [ V DP ], János
pedig
minden fiúnak odaadta az ajándékot.
Closed class lexical items in sentence processing
46
Mary/nom every
girl-to
John/nom whereas every boy-to gave the present-acc
'MARY [gave the present] to EACH GIRL , and JOHN gave the present to EVERY BOY'.
P: * A lány
a Jánosnak.. meg
The girl-sing
John-to
a fiúk is
hát.. odaadta
neki
az ajándékot.
and the boy-pl too well gave3sg/past to him/her the present-acc
Ungrammatical person-number inflection on the Verb. Ungrammatical copy of person-number features of elliptic conjunct into the licensing clause (29) E: A gyerek a ‘’villamosra,[
] a férfiak pedig a ‘’buszra szálltak fel.
the child-NOM sg. at the train-LOC , men-pl.NOM got-pl.PAST up It is the train that the child (got on), it is the bus that the men got on.
P: A gyerek a ‘’villamosra, [
] a férfi pedig a ‘’buszra szállt fel.
the child-NOM sg. at the train-LOC, man-sg NOM at the busz-LOC got on-3sg..up
In the response: ungrammatical Aux and Tense marker attached to the Verb. First and second clause are mixed with each other: Ungrammatical copy of person-number features of elliptic clause into the licensing clause (30) E: Holnap Mari
fog,
tegnap meg
tomorrow Mary-NOMsg3 will-sg3 [
írt
egy verset.
], yesterday then she-NOMsg3 wrote-PASTsg3 a poem-ACC
It is Mary who will (write a poem), it is he who wrote a poem yesterday.
*P: Tegnap Mari
fog ....
tegnap Mari,
tegnap
pedig
fog
írni
egy számlát. yesterday Mary-NOM will-sg3 yesterday Mary-NOM, yesterday however he-NOM will-sg.3 writeInf an invoice-ACC.
First elliptic clause is completely ungrammatical and fragmented. Ungrammatical distribution of case endings (31) E: Péter
First elliptic clause is neglected (32) E: Én nem tudom, hogy "mikor [ S2 ] I
not know
that when
de .Erzsi "London-ban tanult angolul,
. but Liz
London-in
learned English
' I do not know when, but Liz has learned English in London.'
P: Tanult angolul Londonban .. valaki... (he/she) learned English in London, someone...
6.4. A post-hoc analysis of data 6.4.1. Identification asymmetries between FVPE and BVPE (the different levels at which identity is checked) are relevant for the real sentence processing operations.
Repetition of BVPE imposed Syntax/Phonology interface requirements that exceeded the impaired capacity of language processor with agrammatic aphasics. At least two types of operations are required in the processing of ellipsis. The processor needs to be able to look ahead and look back over some number of successive items or structures, to store a linear array of lexical items. Processes based on rapidly assigned surface syntactic representations. There must also be means of storing items or structures that are not yet complete, to which additional surface material can subsequently be attached. This is one of the functions that is performed by order preserving phonological buffer, a type of short-term memory (Martin and Saffran (1997). 6.4.2. Producing co-ordinated sentences with FVPE in a repetition test requires the patients to store content-based representation of co-ordinated sentence heard, then convert it into surface syntactic and phonological form. Supposing the processor builds structures incrementally, from left to right, there was no built-in delay in processes because of direction of ellipsis. Patients often mentioned elided VP in overt phonological form at its correct position in second conjunct. It was easy for them to reconstruct FVPE in overt phonological form. Order preserving phonological buffer linked phonologically overt antecedent to dependent lexical items with lacking phonological form in the second conjunct. To produce co-ordinated sentence with BVPE in repetition test, it is necessary to recover the omitted lexical items in first conjunct. Supposing the processor builds structures incrementally, from left to right, there is a built-in delay in operations because of direction and identification level of backward VPE. (Recovering is delayed, because the elided material is located in the first clause, and the phonologically overt licensing string is found in the second clause). Order preserving phonological buffer should serve a place holding function for VP ellipsis site, ensuring that elided material is recovered and order information is maintained despite backward direction. Patients were able to repeat mostly the second clause in correct grammatical form. The first elliptic clause often was fragmented and ungrammatical. Elided VP in first clause rarely was mentioned in its overt phonological form. This is because the demands of task increased to the extent that exceeded the capacity of impaired processor.
48
Closed class lexical items in sentence processing
6.4.3. The data characterized above are relevant from the point of view of a time-based parser. The differences are related to timing. Generally speaking, when a non-empty Verb appears, most of the pieces to properly assemble the clause are available. In case of backward ellipsis the question is the following: how to build a sketchy structure for the FIRST clause without the lexical material of a V-bar. In case of forward ellipsis, the parser processes the lexical material of antecedent V-bar in the first place, then tries to analyse an empty category later. An empty (elided) category can be detected by means of surface structural parallelism. According to parallelism, a „later“ empty category is the same type as its antecedent category and both of them must occur in same type of syntactic positions in the first and the second co-ordinated clause, respectively. The role of parallelism is important. At the very moment when a parser detects an empty category of V-bar, the parser tries to find an antecedent V-bar whose lexical material has been processed earlier and makes use of the processed lexical material of that V-bar once again in the building of the second clause. Forward ellipsis is easier for impaired speech, because the same category is used twice in two parallel structures but the overt lexical form is mentioned only once. Backward ellipsis can be harder for the time-based parser. Backward ellipsis means: an empty category is detected at first. At the very moment when a parser detects an empty V-bar there is no information about the subtype of it and no information about the lexical material of V-bar. The decision is postponed. The parser must put that empty category into memory buffer and wait for a posterior lexical item: the licensing lexical material of a posterior V-bar in the second clause. After processing the posterior V-bar the parser tries to determine the identity of the phonological form of the posterior V-bar and the elided V-bar and copy back semantic-syntactic features associated to the phonological form of the posterior licenser. At this stage, the direction of operations contradicts to the incremental structure building, which is a fundamental processing principle. 6.6. A hypothesis on the structure of mental parser Suppose the following structure-building operations. The mental parser must produce structural frame for all possible sentences. This syntactic frame contains categorized slots. When the configuration of surface case endings assigned by category of Verb to its complements and the configuration of other closed class items are in their active phase in working memory, they define and open up syntactic slots for content word filler. Content-words would be generated by lexicon and would be inserted into their slots in the syntactic frame. Because, closed class items have to be integrated with their categorized slots in the syntactic frame, and open class (content) words have to be inserted into their categorized slots in the syntactic frame as well, these two kinds of integration require synchronization, synchronized activation of structure building elements in working memory for language. The slow activation or fast decay of closed class items leads to a desynchronization between syntactic slots opened up by closed class items and active phase of content word fillers. We define mental parser as an automatic device that becomes specialized in processing of categories and features, involved in grammatical representation of sentences. Under this view parser is a device that transfers information between grammatical representation and message level representation. Parser computes grammatical representations of sentences and transforms them into message level representation (at which the „what is to be said“ is represented). The category and feature system is hierarchical in grammatical representation. It has various levels of sub- and sub-sub categories, from the bare category to the individual lexical item and from the closed class category to the fully specific features of that closed class item. Then, it is the question of capacity and synchronization how far down the hierarchy in grammatical representation, the parser goes on its search for information. The distribution of patients’ performance in tests reflects the limitations on the interface between impaired parser and grammatical representation containing a hierarchy of categories and their features.
49
Closed class lexical items in sentence processing
References Bartos, H. 1998. VP-Ellipsis and Verbal Inflection in Hungarian, ms. Bánréti, Z. 1994. Coordination and Ellipsis, in The Syntactic Structure of Hungarian. Syntax and Semantics ( É.Kiss K. -Kiefer F.(Eds.)) Volume 27, 355 - 414. New York, Academic Press. Biassou, N, Tyler, L.K., Nespoulous, L.J., Dordain, M., Harris, K.S. 1997. Dual Processing of Open and Closed-Class Words, Brain and Language Vol 57, 360-373. Bock, K. 1989. Closed class immanence in sentence production. Cognition, 31. , 163-186.
É.Kiss, K.- Kiefer, F. (eds.) 1994 The Syntactic Structure of Hungarian. Syntax and Semantics Volume 27, New York, Academic Press. Caramazza, A. 1990. (ed.): Cognitive Neuropsychology and Neurolinguistics, Lawrence Earlbum Associates, Publishers. New Jersey.
Chomsky, N 1995. The Minimalist program, Cambridge, Mass.: MIT Press. Chomsky N. 1997. Language and Mind: Current Thoughts on Ancient Problems, Universidade de Brasilia, Pesuisa Linguistica, 3,4, 21 p. Cornell, T. L. 1995. On the Relation between Representational and Processing Models of Asyntactic Comprehension. Brain and Language Volume 50, 304-324. Frazier, L. - McNamara, P. 1995. Favor Referential Representations. Brain and Language 49, 224-240.
Friedmann, N. -Grodzinsky, Y. 1997. Tense and Agreement in Agrammatic Production: Pruning the Syntactic Tree, Brain and Language, 56, 397-425. Haarmann, H J. and Kolk, H. J. 1994. On-line Sensitivity to Subject-Verb Agreement Violations in Broca's Aphasics: The Role of Syntactic Complexity and Time. Brain and Language Volume 46, 493 - 516. Halle, M - Marantz A. 1993. Distributed Morphology and the Pieces of Inflection. In: The View from Building 20, ed.: Keyser S.J. –Hale K.. MIT Press 111-176. Kolk, H. H. J., & Hofstede, B. M. T. 1994. The choice for ellipsis: A case study of stylistic shifts in an agrammatic speaker. Brain and Language, 47, 507--509. Kolk, H. J. 1995. A Time-Based Approach to Agrammatic Production. Brain and Language Volume 50, 282303. Linebarger, M.C. 1990. Neuropsychology of Sentence Parsing, In: Caramazza (1990) (ed.) , 55-122.
Linebarger, M. C. 1995. Agrammatism as Evidence about Grammar. Brain and Language, Volume 50, 52-91. Martin N. and Saffran E.M. 1997. Language and Auditory-verbal Short-term Memory Impairments, Cognitive Neuropsychology, 14 (5) 641-682. Mészáros, É. (1999 ) Immediate Recalling of Sentences Containing a VP Ellipsis in a Broca’s Aphasic Patient. ms Pléh, Cs. 1998 A magyar morfológia pszicholingvisztikai aspektusai, (Psycholinguistic aspects of the Hungarian morphology) in press: Strukturális magyar nyelvtan 3. Morfológia (Structural Hungarian Grammar. 3. Morphology (ed.: Kiefer F.) Akadémiai kiadó, 2000. Pollock, J.Y. 1989 Verb movement, UG and the structure of IP. Linguistic Inquiry, 20, 365-424. Wilder C. 1997. Some Properties of Ellipsis in Coordination, in: A. Alexiadou-T.Hall (eds): Studies on Universal Grammar and Typological Variation, J. Benjamins, 59-107.
Egyeztetés agrammatikus afáziában
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Egyeztetés agrammatikus afáziában A szintaktikai fa metszése Zoltán Bánréti
Absztrakt A dolgozat a nyelvtanmodellek neurológiai realitásának problémájához szolgál empirikus adalékokkal szolgálni. Az adatokat agrammatikus afáziások neurolingvisztikai teszteléseiben nyertük. Az agrammatikus afáziában tapasztalt egyeztetési, morfoszintaktikai hibák értelmezésére, a korlátozottságok különféle fokozatainak magyarázatára a Minimalista Program keretében a szintaktika fa - metszés hipotézisének egy kiterjesztett változatát javasoljuk. 1. A neurolingvisztikai vizsgálatok a nyelvtant olyan környezetben írják le, melyben a nyelvtan beágyazott az agy architektúrájába, interfész pontokon kapcsolódva az agy és az elme mentális programjaihoz. A nyelvtanelméletek számára pedig ma már lehetséges kutatási cél olyan nyelvtan modellek felépítése, amelyek konstrukciója a mentális nyelvtant, vagyis a beszélők agyában reprezentált nyelvtan felépítését, tulajdonságait fejezi ki. 2. Az újabb neurolingvisztikai elméletek többsége (Kolk 1995, Linebarger 1995, Swinney Zurif 1995, Friedmann- Grodzinsky 1997) úgy tekinti a mentális grammatikát, mint egymással összeköttetésben álló agyi területek által tárolt nyelvtani reprezentációk rendszerét, ahol az egyes agyi területek strukturálisan is determináltak valamely specifikus nyelvtani reprezentációtípus tárolására illetve közvetítésére. 3. Az empirikus adatok egy fontos osztálya abból adódik, hogy az agy különböző területein jelentkező lokalizált sérülések -- a gondolkodási és más kognitív képességek épen maradása mellett -specifikus nyelvi károsodásokhoz vezethetnek, a nyelvi képesség valamely részrendszere, részfunkciója sérüléséhez, korlátozódásához, a többi épen maradása mellett. Jobbkezes embereknél a homloklebeny baloldalán, a homloklebeny harmadik agytekervényének hátsó területeit és a precentrális agytekervény ezzel szomszédos alsó területét ért lokális károsodás a beszédprodukciós képességek korlátozódását eredményezi. Az említett régiót Broca területnek nevezik, a nyelvi zavart pedig Broca afáziának. Mai ismereteink szerint a baloldali elülső kérgi területek és a velük szomszédos kérgi területek felelősek azokért a műveletekért, amelyek a beérkező nyelvi input egységeinek a szintaktikai szerkezetbe történő gyors és automatikus szerkesztését végzik el. 3.1. A Broca afáziás betegek nyelvi tüneteinek számunkra legfontosabb sajátossága a szintaktikai és a morfológiai deficit korrelációja. A Broca afáziásokat a viszonylag ép beszédértés mellett elsősorban a beszédprodukció zavara jellemzi. Ez megmutatkozik a mondatfragmentumokat produkáló, töredezett, lassú beszédben, gyakran elhagyott funkciószavakban, és az egyeztető toldalékok, ragok, használatának hibáiban. A beszéd intonációja monoton, artikulációs hibák jellemzik. Az alábbi, lejegyezett spontán beszédben aláhúzással jelöltük az explicit egyeztetési hibákat (A szótalálási, szókeresési nehézségek hatásaitól most el kell tekintsünk). 3.2. Broca afáziás vizsgálati személy, (37 éves férfi, a lézió helye: bal frontális) lejegyzett spontán beszédéből mutatunk be alább egy részletet: Vizsgáló: Mi történt magával? … egyszercsak ujjamban néz, így mi fordult meg.. nem tudo, hogy mi van? És akko így néz.. néz jó..jó.. nem bír mozdítani, nem bírtam egysz ..akkor megmozdulok a kézzel.. azt vár, vár a nem mozdulni a kezem meg a testem. És nem tud, hogy mi van! Egy olyan fél perc.. vegy nem.. egy órára,..hogy hát mondom, várni nem kellni, kellni.. egy orvos. És meg...beszéltük, hogy .....hát ugye ô is, meg a másik is...mer ..mintha máskor szóval mindig a fár.. ház lejjebb, ott van a kórház... Úgy van, ismerek pár orvos ..., hogy mindig, mindig, oda járt...., megisment, elismertem de mondom várj. De nem mehet
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így, . vagy nem! Nem jól mondom, hanem ....szóval átmentünk az izébe,....tehát így a.. olyan kényelemtől már megmondani..na. Egy bizonyos rész, egy olyan.... fél-háromnegyed tíz, tíz óra fele amikor már éreztem..na. És aztán el is vertek, el is vertek (a szándékolt szó: el is vittek) (Mészáros Éva lejegyzése) 3.3. A fent bemutatott adatokban látható az afáziás nyelvi korlátozottság egy fontos mozzanata, a nyílt lexikai osztályú és a zárt lexikai osztályú egységek aktivációjának a szétválásai. A világ objektumait jelölő tartalmas szavak bővíthető osztálya: a nyílt szóosztály. Az morfoszintaktikai egyeztetési szabályok által közvetlen érintett objektumok a zárt szóosztályok tagjai közül kerülnek ki, például az inflexiók, esetragok, névelő, általában a nyelvtani viszonyokat, és nem a világ objektumait jelölő formatívumok. A zárt szóosztályú morfémák a mentális struktúraelemző és struktúraépítő rendszer elemeit alkotják. A mondatfeldolgozás során például jelzik a főnévi szerkezet kezdetét/végét, a fő- és alárendelt mondatok megkülönböztetését és határaikat, stb. A gyors előhívásuk lehetővé teszi a lokális szintaktikai szerkezetről alkotott azonnali döntéseket. A nyílt és a zárt lexikai osztályok aktivációjának valamilyen szétválása sokféle nyelvi deficitnek összetevője lehet. Feltételezhető, hogy a nyílt és zárt szóosztálybeli egységek két különböző “szublexikonban“ tárolódnak melyek külön pályákon érhetők el. Azonban egymáshoz rendezve, szinkronizáltan kell őket aktiválni a mondatprodukció és feldolgozás során. Az agrammatikus afáziások spontán beszédének töredezettsége és agrammatikussága összefüggésbe hozható a zárt lexikai osztályok aktiválásának korlátozottságával. 3.4. Az afáziás korlátozottság nyelvtani viszonylatok mentén is jellemezhető. Ha például csakis a munkamemória korlátozottsága okozna afáziát, akkor nehéz lenne megmagyarázni, hogy miért éppen a lexikai egységek egyik osztályát érinti a memóriazavar, és a másikat nem, hiszen vannak nyílt osztályú lexikai egységek, melyek rövidebbek, fonotaktikailag „könnyebbek“, mint egyes formatívumok. 4. Az afáziás korlátozottság kifejezhetősége a nyelvtanmodellekben 4.1. Feltételezéseink a következők. A mentális nyelvtani reprezentációkat olyan instrukcióhalmaznak tekintjük, melyek instruálják a beszédprodukciót, illetve a beszédfeldolgozást szervező mentális programokat. Egészséges esetben a különféle agyi területeken tárolt nyelvtani reprezentációk, aktiválhatók és (időben) szinkronizálhatók. Az aktivált nyelvtani reprezentációkat a beszédprodukciót vagy a beszédfeldolgozást szervező valós idejű mentális programok mint instrukciókat "olvassák el" azokon az interfész szinteken, melyek a nyelvtan és a mentális programok között vannak. Ugyanakkor a lokalizált agysérülések a nyelvi képesség valamely részrendszere, részfunkciója korlátozódásához vezethetnek, a többi épen maradása mellett, tehát a mentális nyelvtan szétválhat funkcionális komponenseire. Ennek vagy az az alapvető oka, hogy nincsen ép, „elolvasható“ nyelvtani reprezentáció, vagy pedig az, hogy a beszédprodukciós, illetve beszédfeldogozó mentális programok korlátozódnak, egyes nyelvtani reprezentációkat el tudnak olvasni, míg más nyelvtani reprezentációkat nem képesek elolvasni. Feltételezem, legalábbis a nyelvtanelméletek egy osztálya számára, hogy ezeknek a mentális realitással bíró nyelvtani reprezentációknak a tulajdonságai, rendező elvei képezik tárgyukat. Nem ismerek olyan közvetlen és cáfolhatatlan bizonyítékot, amely a nyelvészetben kifejlesztett nyelvtanmodellek valamelyikének – abban a formában, ahogy azok leírtak – a mentális vagy neurológiai realitását igazolná. Valamely nyelvtanmodell egészére nézvést nem tudhatjuk pontosan, mennyire fedi le a neurológiai vagy mentális realitásokat. Ettől azonban meg lehet különböztetni azt a kérdést, hogy van-e mentális vagy neurológiai realitása annak, amit kifejez valamely nyelvtanmodell a nyelvtani reprezentációkról, azok tulajdonságairól, melyeket például a levezetésükben felhasznál?
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4.2. Ami az agrammatikus afáziás korlátozottság jellemzését illeti, ennek kifejezésére olyan nyelvtanmodellek lehetnek alkalmasak, melyekben a szintaktikai szerkezet levezetése és a morfológiai deriváció szigorúan feltételezi, sőt tükrözi egymást. Ebben az esetben a beszédprodukcióban megnyilvánuló morfoszintaktikai korlátozottságok összefüggésbe hozhatók a szintaktikai szerkezet építésnek korlátozottságával, töredezettségével. Chomsky a Minimalista Program keretében például ilyennek tekinti a nyelvtani reprezentációknak olyan tulajdonságait, melyek lehetővé teszik, hogy – az interfész szinteken-- a nyelvtani reprezentációk, mint instrukciók, tökéletesen elolvashatóak legyenek a külső szenzomotoros mentális programok számára (beszédprodukció, beszédfeldolgozás), illetve a külső konceptuális mentális programok (jelentés/interpretáció) számára (Chomsky 1999). 4.3. Az agrammatikus afáziának, egyebek mellett, van három olyan empirikus sajátossága, melyek egymással összefüggésben jelennek meg. (Kolk, 1995, Linebarger, 1995, Pléh 1998.) Ezek a következők: 4.3.1. A morfológiai zavarok. Az agrammatikus betegek hajlamosak a zárt szóosztályok tagjainak, az inflexiók, ragok, névelők stb. elhagyására, néha helyettesítésére. Ugyanakkor a “nyitottosztályú“ szótár (tartalmas szavak) viszonylag megőrzöttek. Megnevezési feladatokban azonban a Broca afáziásoknak több nehézségük van az igékkel, mint a főnevekkel. 4.3.2. A morfológiai deficit szintaktikai korlátozottsággal jár. Az afáziás betegek a nyelvtani formák, szerkezetek nagyon szűk körét alkalmazzák, nagyon rövid, egyszerű kijelentő mondatokat használnak a szokványos szórenddel. Ritkán produkálnak mondatbeágyazásokat, nagyon kevés bővítményt használnak. 4.3.3. A zavarok harmadik osztálya a beszéd lelassulása és töredezettsége. A lelassulás monoton intonációval jár együtt, a szintaktikai pozíciókhoz társult nyomatékokat (fókusz, kvantor nyomaték) sem produkálják. A töredezettség pedig a „mondatdarabok“, fragmentumok produkálásában nyilvánulhat meg. (non-fluens beszéd.) 4.4. Összefoglalóan azt mondhatjuk, hogy az agrammatikus afázia alapvető nyelvi tünete a szintaktikai és a morfológiai korlátozottság együttjárása és összefüggése non-fluens, fragmentizált beszédprodukcióval. Ez a megfigyelés olyan neurolingvisztikai elméleteket inspirált, melyek a Minimalista Program keretein belül gondolkodnak. (Chomsky, 1995). Ezek az elgondolások az MP által követett komputációs lépések neurológiai realitására keresnek adatokat és érveket. A Minimalista Program egyik elve ugyanis éppen az, hogy a szintaktikai szerkezet levezetése és a morfológiai deriváció feltételezik és tükrözik egymást. A szerkezetépítő műveletek a lexikonból szelektált egységekhez nem adnak hozzá új információt vagy jegyet, hanem a lexikai egységek adott grammatikai-kategoriális jegyeinek az ellenőrzését, egyeztetését végzik. Ehhez szükséges a kritikus jegyek lokális szerkezeti relációkban való ellenőrzése, egyeztetése, a lexikai egységek szintaktikailag helyes sorrendbe állítása. 5.1. Hagiwara (1995) a nyelvtani reprezentáció és a mentális feldolgozó kapacitás között a következő összefüggést tételezi fel. Azok a szerkezetek, amelyeket a szintaktikai fastruktúrában alacsonyabb szintű csomópontok dominálnak, olyan felépítő műveletet kívánnak meg, amely rövidebb idő alatt elvégezhető. A lexikális egységeket összekombináló, szerkezetépítő műveletnek (Merge, Chomsky, 1995)) tehát kevesebb lépést kell elvégeznie, mert alacsonyabb szinten levő csomópontot kell megépítenie. Ez az agrammatikus betegek számára gazdaságosabb és könnyebb. A mondatszerkezetben lexikai és funkcionális fejeket tartalmaz. A funkcionális fejek, mint például a Tense, az AgrS, AgrO absztrakt morfológiai jegyeket dominálnak. A szerkezetépítő műveleteket, a mozgatásokat az vezérli, hogy a jegyek, köztük a morfológiai jegyek megkívánják az ellenőrzést. Minden jegy-ellenőrzés valamely szerkezeti projekció Spec-Head viszonylatában történik. A mondatok a funkcionális projekciók sokszoros rétegzéseivel építődnek fel. A funkcionális fejek hozzáadása vagy kombinációval (Merge) vagy a kombinációnak a csatolásával történik, amely kombinál két fejet, mint például a Tense és az AgrS fej, és egy Tense-AgrS komplexumot formál. A
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Spec pozíció helyettesítéssel megépített, például a szerkezetépítő művelet összekombinálja a (Specbeli) tárgyat és az AgrO' –t, ami projektál egy új kategóriát: az AgrOP-t. Ezekhez és a hasonló műveletekhez, Hagiwara érvelése szerint produkálási vagy feldolgozási költséget rendelhetünk. A költség terminussal az „economy“ elvre utal Hagiwara, abban az értelemben, hogy egy adott nyelvben a szerkezetépítő műveletek lehetséges tárházából azt a változatot választjuk, amely az adott nyelv típusa, inflexiós rendszere stb. alapján a minimális ráfordítást igényli, megtoldva azzal, hogy agrammatikus afáziában ehhez a mentális memóriatárolók (procedurális, deklaratív és munkamemória funkciók) korlátozottságát is figyelembe kell venni. Ez azt jelenti, hogy a sérült szerkezetépítő műveletek memória tároló igénye radikálisan megnőhet a normál esethez képest. Az agrammatikus afáziás személyek olyan komplexitású mondatreprezentációk megépítésére törekednek, melyek még összehangolhatók a memóriatároló kapacitással, ezek lesznek a számukra gazdaságos szerkezetek. Ezeket a feltételezéseket számos nyelven végzett empirikus kutatással motiválták. 5.2. Hagiwara (1995) japán afáziásokkal végzett teszteléseinek eredeménye az volt, hogy az agrammatikus afáziások hibás mondatszerkezetei mögött olyan sérült szintaxis áll, melyben a szintaktikai fastruktúrán belül a funkcionális kategóriák károsodtak. A funkcionális kategóriák a szintaktikai szerkezet azon csomópontjai, amelyek a grammatikai morfológiát dominálják. Hagiwara tesztjeiben az agrammatikus afáziások TenseP-én vagy AgrP-én belül ( e csomópontok alatt) tudtak konvergens reprezentációt létrehozni, és nem a CP -én belül. Innen a megértési nehézségek (aszintaktikus értés) és a produkciós korlátozottságok. Az AGR csomópont az igei egyeztetés morfológiáját dominálja, a C csomópont pedig a mondatot bevezető kötőszókat. Minden ilyen csomópont a szintaktikai fastruktúra egy bizonyos szintjén helyezkedik el. A betegek nyelvi korlátozottsága ezért úgy jellemezhető, mint a szintaktikai fastruktúra egy bizonyos szintjén fellépő zavar. Azok a grammatikai morfémák, amelyek a kritikus szint alatti csomópontoktól függnek, a betegnél megtartottak, míg azokat a morfémák, melyek a kritikus szintnél magasabb csomóponttól függnek, már korlátozottak. Hagiwara kimutatta, hogy a japán agrammatikus betegek kevés hibát vétenek a tagadó kifejezésekkel, az idői egyeztetéssel, és a nem alanyesetű főnevekkel. Ezek a NegPtől, illetve a TensP-től, illetve az AgrOP csomópontoktól függnek, melyek a szintaktika fastruktúra viszonylag alacsonyabb szintjein vannak a japánban. Ugyanakkor sok hibát vétettek a mondatbevezető kötőszavakkal, a kérdő kifejezésekkel, a kérdő partikulával és az alanyi DP-hez kapcsolt nominatívuszt jelölő, topikot jelölő, illetve genitívuszt jelölő partikulákkal kapcsolatban. Ezek a CP, az AgrSP, illetve a TopicP csomópontoktól függnek, melyek magasabban vannak a szerkezeti hierarchiában, mint a Tense csomópont. 5.3. Friedmann és Grodzinsky (1997) olyan héberül beszélő afáziás betegről számol be, aki a mondatismétlési és mondat-befejezési feladatok során az alany-ige egyeztetés morfológiájában szinte egyáltalán nem követ el hibákat, viszont az ige idői egyeztetése, inflexiója során sok hibát követ el (például nem kompatibilis a mondatban használt időhatározó jelentése és az ige idői inflexiója). Friedmann és Grodzinsky magyarázata az, hogy a héber nyelv mondattana esetében a szintaktikai fában az AGR csomópontok alacsonyabb szinten helyezkednek el, (ezek a betegük számára elérhetőeknek bizonyultak) viszont az ige idői morfológiáját domináló Tense csomópont a szintaktikai fastruktúrában magasabb szinten van (és az adott beteg számára nem elérhető). Ennek a betegnek a deficitje tehát a Tense szinten van. Friedmann-Grodzinsky feltételezi: ha valamely betegnek egy adott csomópont tekintetében károsodása van, akkor a szintaktikai fastruktúrában az ennél magasabb szintek csomópontjai elérhetetlenek lesznek. A fastruktúra megépítésekor ugyanis az egyeztetésekhez szükséges az ige felfelé mozgatása bizonyos csomópontokon keresztül, de az ige nem mehet át a “károsodott“ csomópontokon. Ennek a heurisztikusan nagyon értékes elképzelésnek hiányossága az, hogy nem ad számot arról, hogy a baloldali frontális lebeny sérülése következtében fellépő afáziák nyelvi tünetei nagyon sokfélék, változatosak lehetnek, a súlyosabb korlátozottságtól az enyhébb korlátozottságokig terjedő skálát alkotva.
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6. Mondatismétlési tesztek magyar anyanyelvű afáziásokkal 6.1. A tesztek során élőben vagy hangszalagról lejátszott mondatok változatlan formában történő megismétlésére kérjük a vizsgálati személyeket. Az adatokból jól látható, hogy a teszt teljesítése megkívánja a célmondat tényleges feldolgozását, a jelentésreprezentáció tárolását, majd annak olyan szintaktikai szerkezetben és fonológiai formában történő produkálását, mely hasonlít a célmondatéhoz vagy egyezik vele. A vizsgálati személyek mindegyike válaszaiban olyan stratégiát követett, melyben megkísérelte egymásra leképezni a hallott mondathoz általa rendelt szemantikai interpretációt, a hallott mondat eredeti szintaktikai szerkezetét, és az eredetivel lehetőleg azonos fonológiai formát. A következőkben három, különböző vizsgálati személlyel végzett tesztekből mutatunk be példákat. 6.1.2. I. afáziás vizsgálati személy: S., 37 éves férfi, traumás eredetű, baloldali frontális és temporális területű bevérzés. A vizsgálati személy válaszai korlátozottságot mutatnak mind az esetragok, mind az idői inflexió mind pedig a személy-szám egyeztető inflexiók produkálásában. A beteg 73 válaszából csak 2 esetben produkált olyan mondatot, melyben hibás az esetrag de ugyanakkor hibátlan az idői valamint a személy/szám egyeztetés. Példák a fennmaradó 71-ból: (V: vizsgáló, bold –dal szedett: az afáziás válasza) V: Megjavítottam az autómat, de újra elromlott. Autó…. autó ..szokott csinálni, meg szokott csinálni.. hogy menni..
V: Vendégeket vártam, de nem jöttek. Nem bírok várni őket, hanem a nőt mond, hogy maradok. Hát mondok, akkor maradok, maradok, mert annyira mondta szépen én. (tillik nekem)
Spontán beszéd (részlet) V: Mikor engedik haza? Nem szokott tudni.. Azér otthon azér csak jobb lesz azér, mer nem nem egymaga leszek, És akkor legalább ottan míg beszél még jobban leszek mint én igaz?… (tillik: jobban leszek mint ahogy most vagyok én 6.1.3. II. afáziás vizsgálati személy: I.N. 57 éves nő, bal frontális-parietális hypodensitas A beteg válaszaiban grammatikus esetragokat használ, grammatikus az idői inflexió, viszont hibás a személy/szám egyeztető inflexió az igén. A beteg kompenzációs stratégiát is alkalmaz: az alanyt vagy elhagyja, vagy a szintaktikai fában „lejjebb“ helyezi, az ige utánra:
--az alany elhagyása
V: Az autó "elsuhant a ház előtt. Elsuhant a ház előtt.
V: Az igazgató "elküldte vidékre a sofőrt. Sofőrt, sofőrt akkor "vidékre küldte.
Egyeztetés agrammatikus afáziában
55
-- az alanyt az ige alá
V:A lámpák késő estig világítottak. Késő estig világított… az.. a lámpák.
V: A biciklista semmiről sem tehet. Sem semmiről sem evett a biciklista.
6.1.4. A prozódiai korlátozottság és szintaktikai korlátozottság összekapcsolódva, együttesen jelenik meg a II. afáziás vizsgálati személy válaszaiban. Az agrammatikus afáziásoknál gyakran mind a beszédprodukció, mind pedig a beszédértés egyidejűleg valamilyen módon károsodik. Egyrészt korlátozott és jellegzetesen monoton intonációt produkálnak, másrészt a prozódiailag jelölt szintaktikai kategóriák feldolgozása hibás lehet. Nagel és Shapiro (1994) egészséges személyek és afáziások rögzített beszédét analizálva azt találták, hogy az afáziások nem produkálnak nyelvtani szempontból normál dallamot a mondatokon belüli hosszabb tartományokban, és nem produkálják a szintaktikai pozíciókhoz társítandó kontrasztív nyomatékokat, és azt megelőző dallamot és időtartam nyújtást. A szerkezeti pozíciókhoz társított prozódia közreműködik annak meghatározásában, miképpen kapcsolódnak össze lexikai és szerkezeti kategóriák a mondatstruktúrában. A prozódiai információ valószínűleg nagyon korán, a kezdeti elemzés során felhasználásra kerül annak érdekében, hogy segítsen a mondatfeldolgozás során felmerülő csatolási kérdések eldöntésében, hogy a szerkezet feldolgozása során fellépő bizonytalanságokat megoldja. Nagel és Shapiro szerint az afáziások nem képesek a megfelelő időben felhasználni a prozódiai információt a hallott mondatszerkezet on-line feldolgozásában. A mi adataink is alátámasztják Nagel és Shapiro eredményeit. A magyar anyanyelvű afáziások a beszédprodukcióban kikerülik az erős nyomatékot hordozó fókuszt, a tagadott fókuszt és a kvantoros kifejezéseket, és helyettük a szintaktikai fában "lejjebb" helyezett, nem nyomatékos változókat produkálnak. Mivel csak késve képesek vagy egyáltalán nem képesek időben felhasználni a prozódiai információt a szerkezeti viszonylatok meghatározásában, ezért például a fókuszra olykor hibás, töredékes szerkezet feldolgozásokat végeznek. A mondat megértésében pedig fennakadásokat, nehézségeket okozhat a fókusz interpretációja és a kvantoros kifejezés értelmezése: Ezt tapasztaltuk a II.-vel jelölt vizsgálati személy esetében is. Néhány példa:
elhagyás Tagadó operátor törlése: V: A vezetőt NEM idegesítette a zaj. A vezetőt idegesítette a zaj.
-- a kérdőszó helyett hasonló változó lejjebb a szintaktikai fában: V: Kit láttál az utcán? ..Hogy az utcán ment valaki, az utcán.. az utcán mentél.
V: Mikor érkezett meg a pécsi gyors? Igen, a.. hogy a pécsi gyors, az.. valamikor megjött.
A fókusznyomatékot nem produkálja: V: MARI hajtotta biciklit gyorsan és PÉTER [
].
Tehát .. mindenki hajtott gyorsan , Mari is meg Péter is.
6.1.5. III. afáziás vizsgálati személy: Sz. V. 42 éves férfi, bal oldali frontális hypodensitas. Broca afáziás. Sz. V. mondatismétlési tesztben nyújtott teljesítménye erős függést mutatott a célmondat tulajdonságaitól. Az alábbiakban – az eredetileg random módon tesztelt mondatokat --- a célmondat tulajdonságai szerint rendeztük, és bemutatjuk a vizsgált személy teljesítményét a célmondatok egyes csoportjaira. Három csoportot találtunk. I. oszlop: a neutrális intonációjú célmondatok. A beteg válaszaiban nincsen raghiba, de vannak hibás egyeztető inflexiók az igén: alany-ige, tárgy-ige egyeztetésbeli hibák. II. oszlop: olyan fókuszos célmondatok, melyekben az alany a topik pozícióban, a tárgy/határozó pedig a fókusz pozícióban van. A beteg válaszaiban hibás ragokat és hibás egyeztető inflexiókat produkál, de mindig sikeresen aktiválja magát az igét. III. oszlop: olyan fókuszos célmondatok, melyekben a tárgy/határozó a topik pozícióban, az alany pedig a fókusz pozícióban van. A beteg válaszaiban hasonló mennyiségű a hibás ragot és hibás egyeztető inflexiót produkál, mint a II. oszlop mondatainál, viszont most a 12 mondatból 3 mondatban nem képes aktiválni magát az igét. Ezek szerint a beteg számára az I. oszlop célmondatai a viszonylag könnyűek, a II. oszlop célmondatai nehezebbek, mint az I. oszlopé, és a III. oszlop célmondatai pedig nehezebbek, mint a II. oszlopé: I.
II.
III.
V: Te felszedted a szemetet.
V: Te a SZEMETET szedted fel.
V: A szemetet TE szedted fel.
Te fele le felszed.ted a szemetet.
Én sz.. szeme.tet szedem
* Szemetet szemetek Te
V: Ő kitisztítja a cipőt.
V: Ő a CIPŐT tisztítja ki.
V: A cipőt Ő tisztítja ki.
*Ő ktit ki tiszti.. tom a cipőt.
*Ő cipőt tisztítja ki.
*Cipőt ő tisztítja.
V: Mi szántjuk a földet.
V: Mi a FÖLDET szántjuk fel.
V: A földet MI szántjuk fel.
Mi szánt.. juk a föl..det.
Mi a földet szánt…juk ki.
*Fö… nem tudom
Egyeztetés agrammatikus afáziában
57
V: Ti gurítjátok a követ.
V: Ti a KÖVET gurítjátok el.
V: A követ TI gurítjátok el
*Én gurigá..gurit..ják a krövek
*Mi a követ gurit..já..tok ki
*Követ ki ti követ ki
V: Ők megterítik az asztalt.
V: Ők az ASZTALT terítik meg.
V: Az asztalt ŐK terítik meg.
*Ő megterít a.. az asztalt.
*Ő a.. asztal terít..t..t..
*Asz..talna asztal Ők terít meg.
V: Én megkapom a szemüveget.
V: Én a SZEMÜVEGET kapom meg.
V:A szemüveget ÉN kapom meg.
Én meg ka..pom a szemüve..get
*Én a sze.mü.ve.get rakod ki.
*Szemüveg én kapom meg.
V: Te kimosod a zoknit.
V: Te a ZOKNIT mosod ki.
V: A zoknit TE mosod ki.
*Én én mos..sok a zoknimat.
Én a zoknit mosom ki.
*Zokni Te mosol ki.
V: Ő kifizeti a számlát.
V: Ő a SZÁMLÁT fizeti ki.
V: A számlát Ő fizeti ki.
Ő ki.fi.ze.ti az számlát.
Ő a szám.lát fi.ze.ti ki
Számj számláját ő fizeti ki.
V: Mi ki dobjuk a virágot.
V: Mi a VIRÁGOT dobjuk k i.
V: A virágot MI dobjuk ki.
Én ki.do.bom. a ssz
Mi a…..
Virág…
Mi ki.dob.juk a vi.rá.got
*Mi a virág dobjuk ki.
*Virágot mi dobjuk ki.
V: Ti várjátok az ünnepeket.
V: Ti az ÜNNEPEKET várjátok.
V: Az ünnepeket TI várjátok.
Ti vár.játok a ünnepekt
Ti a ünnepeket…..
*Ünnepeket ti várjuk.
Mi a ünnepeket *Ünnepek várjá..taok V: Én felszálltam a buszra.
V: Én a BUSZRA szálltam fel.
V: A buszra ÉN szálltam fel.
Én fel.szál..lok a busz.ra.
Busz..ra száll fel.
*Buszba fel…szed
V: Ők kinéznek az ablakon.
V: Ők az ABLAKON néznek ki.
V: Az ablakon ŐK néznek ki.
Ő ki.néz az ablakon.
*Ő az ablakot nézek ki.
*Ablakot ő nézik ki.
ÖSSZES HIBA: 6/12
ÖSSZES HIBA: 10/12
ÖSSZES HIBA: 17/12
2 Agr + 2 Def
3 Agr + 3 Def
3 Agr + 3 Def + 3 igehiány
1 tárgyraghiány
3 tárgyraghiány
3 tárgyraghiány 3 hibás esetrag
1 időváltás
1 időváltás
2 időváltás
A beteg tesztválaszaiban a topik/alany és a fókusz/alany az igével való személy/szám egyeztetés szempontjából nem mutat különbséget. Ugyanakkor az ige aktiválása szempontjából sokkal könnyebb konfiguráció a topik/alany + fókusz/tárgy, mint a topik/tárgy + fókusz/alany. Az esetragok kiosztása tekintetében nincs nagy különbség a fókusz/bővítmény és a topik/bővítmény között. A fókuszos mondatoktól eltérően, a neutrális célmondatokra adott válaszaiban a beteg nem követett el raghibát, és mindig produkálta az igét.
58
Egyeztetés agrammatikus afáziában
7. 1. A tesztjeinkben nyert adatok értelmezésére a következőket javasoljuk. a) A bal frontális lebeny és a szomszédos agyterületek sérülése eredményeként kialakuló agrammatikus afáziák szerkezetépítő és morfológiai korlátozottságokat egyaránt mutatnak. b) Elfogadjuk a tükörelvet (Baker 1985). Az elv azt mondja ki, hogy a nyelvekben (különösen a gazdag inflexiós rendszerrrel rendelkezőkben) a morfológiai deriváció ( a szó szoros értelemében) közvetlenül tükrözi a szintaktikai derivációt. A morfémák és a morfok abban sorrendben csatlakoznak egymáshoz, ahogyan a szintaktikai szerkezetépítő lépések, (kombinációk, csatolások) végbemennek. c) A tükörelvet alapvetőnek tekintjük, és feltételezzük, hogy a sérült nyelvtani reprezentációkban -- amennyiben a sérülés mértéke nem katasztrofikus – a tükörelv megmarad, és a korlátozottság manifesztálódásában szerepet játszik. Ezért az agrammatikus afáziások morfológiai korlátozottsága valójában szintaktikai korlátozottságot tükröz. 7.2. A fenti keretben a vizsgálati személyektől a mondatismétlési tesztekben nyert eredményeink értelmezhetők a szintaktikai fa metszésének hipotézise keretében. A szintaktikai fa metszésének hipotézise a következőket jelenti. Az agrammatikus afáziában: a) A szintaktikai reprezentációban vagy a Case vagy a Tense vagy az Agr csomópontja a fastruktúrában alulspecifikált lehet. b) Egy alulspecifikált csomópont nem terjeszthető ki (nem projektálható) tovább. c) Mennél lejjebb van a sérült, alulspecifikált csomópont, annál több a felette levő és már el NEM érhető funkcionális csomópontok száma, így annál súlyosabb a korlátozottság. Vagyis az “enyhe“ agrammatizmus csak a magas csomópontokat érinti. Emlékeztetünk arra, hogy a szerkezetépítő műveleteket a lexikai egységek jegyei orientálják, ezeknek az összeillését, egyezését ellenőrzik, és csakis interpretálható jegyeket hagynak meg az ép (konvergens) a reprezentációban. A már levezetett szerkezetbe történik a fonológiai alak beillesztése. Valamely funkcionális fej alulspecifikáltsága morfoszintaktikai hibákban mutatkozhat meg. Ha például alulspecifikált a Tense fej, ahova az ige mozog, akkor ez azzal járhat, hogy a komputációs rendszer nem képes a „szándékolt“ idő (a Tense fejben specifikált jegy) és az ige idői inflexiójának az eltérését észlelni. Így inflexió hibák fordulhatnak elő: a komputáció nem észleli a rossz inflexiót vagy a hiányzó inflexiót. 7.3. Három, eltérő súlyosságú agrammatikus afázia következményeit mutatták a teszteredményeink. (A „súlyosság“ kifejezéssel nem általában a beteg klinikai állapotára utalunk, hanem az agrammatikussság mértékére a beteg nyelvi produkciójában). Kiindulva a magyar mondatszerkezet leírására, Szabolcsi (1997) által a Minimalista Program keretében javasolt struktúrából, a vizsgálati személyek szintaktikai-morfológiai korlátozottságait következőképpen fejezhetjük ki a szintaktikai fa metszéseivel: 1. ÁBRA1
1
Az 1. ábra csakis a jelen tárgyalás szempontjából releváns csomópontokat tartalmazza. Az AgrSP és az AgrOP csomópontoknak a tükörelv által empirikusan csak részben motivált sorrendjének problémájára, valamint az idői és a mód funkcionális projekciói sorrendjének a problémájára nem térünk ki. Jelenleg nincsen olyan afáziás adatunk, melyek ezekkel a csomópontokkal kapcsolatosan a szintaktikai fa metszésére utalnának, miszerint a AgrSP és az AgrOP csomópontok közül egyik csomópont és a kapcsolódó morfoszintaktikai egyeztetés ép lenne, de a másik csomópont és a hozzá kapcsolódó morfoszintaktikai egyeztetés egyidejűleg súlyosan korlátozott lenne. Nincsen erre utaló adatunk a Mod és Finit csomópontokra és a kapcsolódó moroszintaktikai egyeztetésre sem. Ezeket a kérdéseket tehát a további kutatás számára nyitva kell hagyjuk.
Egyeztetés agrammatikus afáziában
59
A SZINTAKTIKAI FA METSZÉSE CP
ToP
DPi
Top`
QP Q’
NegP
FP
DPj
F`
III.
NegP
AgrSP
AgrS’
_i,_j
II.
TenseP
[Múlt]
Tense`
CaseP
Case`
I.
DPk VP
V
_i
_j
_k
I. afáziás: A CaseP alatt, és a VP felett van a fa metszése: az esetragok, az idői inflexió és az egyeztetőinflexiók együttes korlátozódása.
Egyeztetés agrammatikus afáziában
60
II. afáziás: Az TenseP-nél van a fa metszése, (felette korlátozott): ekkor grammatikusak az esetragok, grammatikus az idői inflexió, de hibás a személy/szám egyeztető inflexió az igén. Kompenzáció: alany elhagyása vagy lejjebb helyezése a szintaktikai fában az ige utánra. III. afáziás: Az AgrP-nél van a fa metszése: ekkor neutrális mondatban grammatikusak az esetragok, grammatikus az idői inflexió és a személy/szám egyeztető-inflexió. Viszont a fókuszos mondatokban esetrag, idői inflexió és személy/szám egyeztetés hibák vannak, nagyjából egyforma mennyiségben a fókuszra és topikra. A topik/tárgy és fókusz/alany konfiguráció mellett igeaktiválási zavar keletkezik. 7.4. Az AgrP-nél metszést tartalmazó hibás reprezentációból adódhatnak a csakis fókuszos mondatokban keletkező nyelvtani hibák. Ezek magyarázatára javasoljuk az újraelemzésre vonatkozó hipotézisünket. A hipotézist a következő jelenség magyarázatára javasoljuk. Ha feltételezzük, hogy a kritikus morfoszintaktikai egyeztetések, ellenőrzések az AgrSP-ig bezárólag már megtörténtek, akkor károsodhatnak-e újra az egyeztető végződések, vagy a ragok például a topik vagy a fókusz pozícióban? A lehetőség egyáltalán nem abszurd. Először is erre utal a tesztelt személy válaszmondatai grammatikusságának az erős függése attól, hogy neutrális vagy fókuszos célmondatokra adta-e őket. Figyelembe kell venni továbbá azt, hogy a fókusz és topik feldolgozása csakis a prozódiai információk hatékony felhasználásával történhet (A magyarban nincsen topikot vagy fókuszt jelölő végződés). Említettük, hogy Nagel és Shapiro adatai szerint az agrammatikus afáziások nem képesek a megfelelő időben felhasználni a prozódiai információt a szerkezeti viszonylatok meghatározásában. Láttuk, hogy a magyar anyanyelvű afáziásoknak számára nehézségeket okozhat a nyomatékos fókusz feldolgozása. Ha a prozódiai információ nem használható fel időben a szerkezeti viszonylatok meghatározására, akkor olyan helyezet áll elő, melyben a rendelkezésre álló reprezentáció strukturálisan homályos, nem egyértelmű. Hahne és Friederici (1999) kiváltott agypotenciál vizsgálatai2 azt bizonyították, hogy ilyen esetekben a szerkezet-feldolgozást javító, újraelemző műveletek aktiválódnak. Eközben pedig olyan (újabb) grammatikai hibák keletkezhetnek, melyeket a korábbi reprezentáció nem tartalmazott. A kiváltott agypotenciál vizsgálatok erre neurológiai magyarázatot adnak. Az újraelemző műveletek ugyanis nem azokon az agykérgi területeken mennek végbe, ahol az elsődleges feldolgozás. A mondatfeldolgozással kapcsolatosan négyféle agyi elektromos potenciál adatot találtak, melyek három eltérő idő-ablakkal jellemezhetők. Először a nyelvi inger kezdete után 100-200ms körül, a bal oldali agyfélteke elülső részére kiterjedő néhány millivolt negatív töltésű elektromos potenciált észleltek, amely a lokális frázis-szerkezeti információk feldolgozásával volt kapcsolatos. Másodszor kétféle, egyaránt 400ms körüli, ám eltérő eloszlású negatív bioelektromos potenciált mértek: (a) a nyelvi inger kezdete után 400ms körül, egy bal oldali elülső kérgi területű negatív potenciált, amely az igei alkategorizációs információk és az egyeztető morfológia feldolgozásával hozható kapcsolatba, és (b) a lexikai-szemantikai feldolgozás által kiváltott negatív potenciált, mértek, mely az agykéreg baloldali hátulsó területein volt észlelhető széles kiterjedésben.
2
A kiváltott agypotenciál vizsgálatok. során mérik az agy bioelektromos aktivitását. A betegek fejbőrére --ismert meghatározott beállítási poziciók szerint --- elektródákat tesznek, és mérik a különböző nyelvi ingerek által kiváltott változásokat az agy bioelektromos aktivitásában, amely a nyelvi inger megjelenésével bizonyos idői kapcsolatban áll. A világ különböző laboratóriumaiban lényegében egybehangzó eredményekhez jutottak. Eszerint a mondatfeldolgozási műveleteknek három fázisa határolható el; ezek közül kettő főként szintaktikai természetű.
Egyeztetés agrammatikus afáziában
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Ha a szerkezeti viszonylatok nem egyértelműek, például a prozódiai és a szerkezeti információk egymásra leképezése nem volt sikeres, akkor újraelemzés válik szükségessé. Friederici meggyőző kísérleti és empirikus adatokat szolgáltat arra, hogy az ilyen újraelemzés az előzőktől eltérő agykérgi területekhez kötött és eltérő jellegű: a nyelvi inger kezdete után 600-800 ms között, néhány millivoltos pozitív töltésű bioelektromos aktivitást mutatnak a középső és a hátulsó agykérgi területek, viszonylag széles kiterjedésben mindkét agyféltekén. Az elsődleges feldolgozás és az újraelemző műveletek közti különbségek megteremtik a lehetőséget az újabb nyelvtani hibák keletkezésére: egy korábbi, korrekt morfoszintaktikai és szerkezeti reprezentációt, az őt strukturálisan, kiterjeszteni, egyértelműsíteni kívánó újrafeldolgozás elronthat. Ez a magyarázat összefér mind I.N.-nek teszteredményeivel.
mind pedig Sz. V. –nek a bemutatott
8. Összefoglalás Az agrammatikus afáziában tapasztalt egyeztetési, morfoszintaktikai hibák értelmezésére, a korlátozottságok enyhébb és súlyosabb fokozatainak leírására a szintaktika fa - metszés hipotézisének egy kiterjesztett változatát javasoltuk. Eszerint: 1. A szintaktikai csomópontok sorrendjének megvan a maga komputációs költsége. Az alacsonyabb csomópontok elérése kevésbé költséges, mint a magasabban levő csomópontoké. 2. A tükörelvet úgy egészíthetjük ki, hogy agrammatikus afáziában a
morfológiai korlátozottság szerkezetépítõ korlátozottságot tükröz, a szerkezeti pozíciókhoz rendelt prozódia feldolgozásának korlátozottsága pedig morfológiai hibákhoz vezet. 3. A szerkezeti (frazális) kategóriáknak mennél kisebb számú kombinációja megy végbe, annál gazdaságosabb a szerkezet és annál könnyebben elérhető az agrammatikus afáziások számára. 4. Az agrammatikus afáziások képesek produkálni és megérteni a sérült nyelvtan számára gazdaságos szerkezetet. Így: mennél alacsonyabban van egy funkcionális fej és a projekciója a mondatszerkezeti hierarchiában, annál könnyebben elérhető az agrammatikus afáziás számára. 5. A szintaktikai fastruktúra azon tartományában, amely a diskurzus konfigurációs jellegű, és a nyelvtani alapú nyomaték és intonáció viszonyoktól függő, az agrammatikus afázia prozódiai korlátozottsága olyan újraelemző műveleteket válthat ki, melyek az alacsonyabb tartományban felépített, korrekt morfoszintaktikai reprezentációkat is elronthatnak.
Irodalom Baker, M. 1985. The Mirror Principle and Morphosyntactic Explanation. Linguistic Inquiry 16, 373-415. Chomsky, N 1995. The Minimalist program, Cambridge, Mass.: MIT Press. Chomsky, N. 1999. Linguistics and Brain science, Working Papers in LingisticsVol 8, University of Maryland 104-117. Friederici, A. D,.1995. The Time Course of Syntactic Activation during Language Processing: A Model Based on Neuropsychological and Neurophysiological Data, Brain and Language, Vol 50, 259-281. Hahne A. - Friederici A.D. 1999. Electrophysiological Evidence for Two Steps in Syntactic Analysis: Early Automatic and Late Controll Process. Journal of Cognitive Neuroscience 11:2, 194-205. Friedmann, N. -Grodzinsky, Y. 1997. Tense and Agreement in Agrammatic Production: Pruning the Syntactic Tree, Brain and Language, 56, 397-425. Hagiwara, H. 1995. The breakdown of functional categories and the economy of derivation. Brain and Language, 50. 92-116. Kolk, H. 1995. A Time-Based Approach to Agrammatic Production. Brain and Language 50. 282-303.
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Linebarger, M. C. 1995. Agrammatism as Evidence about Grammar. Brain and Language, 50. 52-91. Nagel, N., & Shapiro, L. P. 1994. Prosody and the processing of filler-gap sentences. Journal of Psycholinguistic Research. [Special Issue] Pléh, Cs. 1998 A magyar morfológia pszicholingvisztikai aspektusai, sajtó alatt: Strukturális magyar nyelvtan 3. Morfológia (szerk.: Kiefer F.) Akadémiai kiadó, 2000. Swinney D., - Zurif E., 1995. Syntactic Processing in Aphasia, Brain and Language, Vol 50, 225-239. Szabolcsi, A. Strategies of Scope Taking, in: A. szablcsi, Ed: Way of Scope Taking, 109-155. Dordrecht, Kluwer.
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Nyelvtan és Mentális Elemző Neurolingvisztikai Megközelítésben Bánréti Zoltán
MTA Nyelvtudományi Intézete 1.1. A neurolingvisztika alapvető kérdésfeltevései közé tartoznak a következők. Milyen szerkezetű a nyelvtan reprezentációja az agyban? Milyen kapcsolat van a nyelvtan moduljai (lexikon, szintaxis, fonológia) és az agy szerkezeti, térbeli felépítése között? Milyen sajátosságokkal bírnak azok a neuropszichológiai mechanizmusok, mentális programok, amelyek a nyelvtani reprezentációkat aktiválják a beszédprodukció és beszédértés folyamatai számára? Másik oldalról, a nyelvtanelméletek számára pedig ma már lehetséges kutatási cél olyan nyelvtan modellek felépítése, amelyek konstrukciója a mentális nyelvtant, vagyis a beszélők agyában reprezentált nyelvtan felépítését, tulajdonságait fejezi ki. A kurrens neurolingvisztikai elméletek többsége (Kolk 1995, Friedmann-Grodzinsky 1997, Linebarger 1995, Zurif 1994) úgy tekinti a mentális grammatikát, mint számos, egymással összeköttetésben álló agyi terület által tárolt nyelvtani reprezentációk rendszerét, ahol az egyes agyi területek strukturálisan is determináltak valamely specifikus nyelvtani reprezentációtípus tárolására illetve közvetítésére. 1.2. Az empirikus adatok egy fontos osztálya abból adódik, hogy az agy különböző területein jelentkező lokalizált sérülések -- a gondolkodási és más kognitív képességek épen maradása mellett -specifikus nyelvi károsodásokhoz vezethetnek, a nyelvi képesség valamely részrendszere, részfunkciója korlátozódásához, a többi épen maradása mellett. Napjainkra már nagyon sok adat gyűlt össze arról, hogy jobbkezes embereknél a homloklebeny baloldalán, a homloklebeny harmadik agytekervényének hátsó területeit és a precentrális agytekervény ezzel szomszédos alsó területét ért lokális károsodás a beszéd produkciós képességek korlátozódását eredményezi. Az említett régiót Broca területnek nevezik, a nyelvi zavart pedig Broca afáziának: 1.ábra
A Broca-afáziás betegeket elsősorban a beszédprodukció zavara, mondatfragmentumokat produkáló, töredezett, lassú beszéd, szótalálási nehézségek, gyakran elhagyott funkciószavak, hiányzó toldalékok és ragok, monoton intonáció, artikulációs hibák jellemzik. Ugyanakkor viszonylag ép a beszéd megértés. Az alábbiakban részletet mutatunk be egy afáziás vizsgálati személy lejegyezett spontán beszédéből. A vizsgálati személy: 37 éves férfi, a lézió helye: bal frontális. A tipikus nyelvtani hibákat aláhúzással jelöltük meg.
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Nyelvtan és Mentális Elemző Neurolingvisztikai Megközelítésben
Vizsgáló: Mi történt magával, hogy került a kórházba? … egyszercsak ujjamban néz, így mi fordult meg.. nem tudo, hogy mi van? És akko így néz.. néz jó..jó.. nem bír mozdítani, nem bírtam egysz ..akkor megmozdulok a kézzel.. azt vár, vár a nem mozdulni a kezem meg a testem. És nem tud, hogy mi van! Egy olyan fél perc.. vegy nem.. egy órára,..hogy hát mondom, várni nem kellni, kellni.. egy orvos. És meg...beszéltük, hogy .....hát ugye ô is, meg a másik is...mer ..mintha máskor szóval mindig a fár.. ház lejjebb, ott van a kórház... Úgy van, ismerek pár orvos ..., hogy mindig, mindig, oda járt...., megisment, elismertem de mondom várj. De nem mehet így, . vagy nem! Nem jól mondom, hanem ....szóval átmentünk az izébe,....tehát így a.. olyan kényelemtől már megmondani..na. Egy bizonyos rész, egy olyan.... fél-háromnegyed tíz, tíz óra fele amikor már éreztem..na. És aztán el is vertek, el is vertek (a szándékolt szó: el is vittek) (Mészáros Éva lejegyzése) 1.3. A Broca afázia lényegét a mondatszerkezet tervezésében és beszédbeli produkálásában mutatkozó zavarok adják. Viszont a Wernicke-terület sérülése, vagyis a baloldali halántéklebeny első agytekervényének hátulsó területét és a szomszédos kérgi területeket ért lokális sérülés más típusú nyelvi károsodást eredményez. A Wernicke afáziás betegek folyamatos viszonylag gyors beszédet produkálnak, amely gyakran értelmetlen, vagy halandzsaszerű szavakból is áll, zavarokat mutatnak a szavak hangalakjának és morfológiai szerkezetének a produkálásában, téves szóhelyettesítéseket, fonemikus, morfológiai és szemantikai jellegű, hibás felcseréléseket produkálnak. Mindehhez társul a hangzó beszéd megértésének erős zavara. A Wernicke afázia legfontosabb jegye a lexikai egységek reprezentációjának, mindenekelőtt a hangformájának korlátozott elérhetősége vagy részleges törlődése adja. A Wernicke afáziások beszédét jellemzi az ún. zsargon-afázia. Például egy Wernicke-afáziás beteg fluens, de nehezen értelmezhető megnyilatkozásai. Lejegyzett spontán beszéd. A vizsgálati személy: 62 éves férfi, Wernicke afáziás. A Zsigulikat, a legislegelső országokat mikor megvették a magyaroknak a magyaroktól, az úgy volt csinálva először, hogy első godás volt. De ez a kis krebekó Trabant az tizen volt vagy tizenegy rágerős, ahová a frajók a rág után jutottak. Eleltem mindent, vároztam országoltam, moszkat, kutást. Mentem hazafelé, azt leesett a lábam. Innen tarboltam le a lábam. De most nem vagyok jól, mert nem tudom észben tartani az eszemből az eszemnek, hogy észben tartsam egészen a szemembe, ami köztünk van. 1.4. Látható a bemutatott adatokban az afáziás nyelvi korlátozottság egy fontos mozzanata, a nyílt lexikai osztályú és a zárt lexikai osztályú egységek aktivációjának a szétválása. A világ objektumait jelölő tartalmas szavak bővíthető osztálya: a nyílt szóosztály. Míg a zárt szóosztály, a nyelvtani viszonyokat jelölő egységeket, formatívumokat tartalmazza, például az esetragok, toldalékok, prepozíciók, determinánsok, névmások, kötőszók, stb. A zárt szóosztályú morfémák egy struktúraelemző és struktúraépítő rendszer elemeit alkotják. A mondatfeldolgozás során például jelzik a főnévi szerkezet kezdetét/végét, a fő- és alárendelt mondatok megkülönböztetését és határaikat, stb. A gyors előhívásuk lehetővé teszi a lokális szintaktikai szerkezetről alkotott azonnali döntéseket. A nyílt és a zárt lexikai osztályok aktivációjának valamilyen szétválása sokféle nyelvi deficitnek összetevője lehet. Például egy szerzett dyszlexiában (olvasászavarban) szenvedő beteg olyan hibákat vétett a tartalmas szavak olvasásakor, melyek egyrészt kifejezik a vizsgálati személy öntudatlan belső tudását a nyílt és zárt szóosztályok különbségéről, másrészt megmutatják azt is, hogy nem tudja zavartalanul használni a lexikonnak azon részét, amely a nyelvtani morfémákat tartalmazza. A vizsgálati személyt arra kérték, hogy olvassa el hangosan a kártyákon egyenként bemutatott szavakat. A beteg a kiolvasott tartalmas szavakról gyakran elhagyta a nyelvtani viszonyt jelölő morfémákat, amikor pedig a nyelvtani toldalékok kiolvasására kérték, a toldalék helyett gyakran tartalmas szót olvasott. Néhány példa:
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Mély diszlexiás paralexiák, zárt szósztály elérési zavarokkal, elhagyásokkal: Nyílt szóosztály olvasása:
Zárt szóosztály olvasása:
CÉLSZÓ KIOLVASOTT SZÓ
CÉLSZÓ
KIOLVASOTT SZÓ
kocsiért >>>> kocsi
-on >>>> otthon
tanárként >>>> orvos
-ba >>>> arra
elrepülök >>>> repülő
-ben >>>> bent
fiaid >>>> fiú
-nál >>>> már
nyaranta >>>> nyár
-tól >>>> ól
ötször >>>> öt
-hoz >>>> ház
tanult >>>>tanuló
-hez >>>> kihez
átszalad >>>> szakadék
-kor >>>> kör
balul>>>> bal váll
-ul>>>>tulajdon
(Kiss Katalin lejegyzése.)
1.5. Feltételezhető, hogy a nyílt és zárt szóosztálybeli egységek két különböző szublexikonban tárolódnak. Ezek külön pályákon érhetők el, azonban egymáshoz rendezve, időben szinkronizáltan kell őket aktiválni a mondatprodukció és feldolgozás során. Sok afáziás esetet jellemez a zárt szóosztályú elemek elérhetőségének a lelassulása. A spontán beszéd töredezettsége és agrammatikussága összefüggésbe hozható ilyen korlátozottsággal. A baloldali elülső kérgi területek és a velük szomszédos kérgi területek felelősek azokért a műveletekért, amelyek a beérkező nyelvi input egységeinek a szintaktikai szerkezetbe történő gyors és automatikus szerkesztését végzik el. Az afáziában azonban a zárt és a nyílt szóosztály aktivációja deszinkronizálódik. Ennek illusztrálására néhány részletet mutatunk be mondatismétlési tesztekből: A vizsgálati személy: 59 éves férfi, a sérülés: baloldali artéria cer. mediális területi hypodensitas. Az alábbiakban V-vel jelöljük a vizsgáló által adott, megismétlendő célmondatokat, és bold-dal jelöljük a vizsgálati személy válaszait. Azonos esetrag több tartalmas szóhoz csatolása: V: A bácsi a NÉNIVEL[
], a fiú meg a LÁNNYAL sétált.
A bácsi a nénivel, a fiúval meg a bácsival, mentél . A gyerekkel ment.
A vizsgálati személy: 37 éves férfi, traumás eredetű, baloldali temporális területű bevérzés. Az esetragok elhagyása, vagy hibás igetoldalékolás, hibás egyeztetések V: Megjavítottam az autómat, de újra elromlott. Autó, autó szokott csinálni, maga. Meg szokott csinálni, hogy akkor...
V: Vendégeket vártam, de nem jöttek. Nem bírok várni őket, hanem a nőt mondta, hogy maradok. Hát mondok, akkor maradok, mert annyira mondta szépen én.
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Spontán beszéd -- részlet V: Mikor engedik haza? Nem szokott tudni.. Azér otthon azér csak jobb lesz azér, mer nem nem egymaga leszek, És akkor legalább ottan míg beszélek beszél még jobban leszek mint én igaz?…
2.1. A mondatfeldolgozás szakaszainak megértése szempontjából különösen érdekesek a kiváltott agypotenciál vizsgálatok. Ennek során mérik az agy bioelektromos aktivitását. A betegek fejbőrére --- ismert meghatározott beállítási pozíciók szerint --- elektródákat tesznek, és mérik a különböző nyelvi ingerek által kiváltott változásokat az agy bioelektromos aktivitásában, amely a nyelvi inger megjelenésével bizonyos idői kapcsolatban áll. Ez lehet negatív vagy pozitív töltésű, néhány millivolt értékű elektromos aktivitás. A világ különböző laboratóriumaiban lényegében egybehangzó eredményekhez jutottak. Eszerint a mondatfeldolgozási műveleteknek három fázisa határolható el; ezek közül kettő főként szintaktikai természetű. Friederici (1995) és Friederici és Hahn (1999) kiváltott agypotenciál kísérleteiben grammatikus és agrammatikus mondatokat vizuálisan, szavanként mutattak be. Az agrammatikus mondatok olyan nyelvtani hibákat tartalmaztak, melyek vagy a szókategóriákkal, vagy a szintaktikai szerkezettel és a szórenddel, vagy az összetevõk lexikai jelentésével, vagy pedig az egész mondat szemantikai interpretációjával függtek össze. Mindig tesztelték a megfelelõ grammatikus változatokat is. A szavak 100ms-ig voltak láthatók egy képernyőn, minden szónál 100ms-os szünetet tartottak, ami előkészítette a kontextust a mondatvégi célszónak, amelyet 200ms-ig mutattak be. A vizsgált személyeknek ebben a feladatban egy késleltetett lexikai döntést kellett hozniuk a mondat utolsó szavára vonatkozóan. A mondatfeldolgozással kapcsolatosan négyféle agyi elektromos potenciál adatot találtak, melyek három eltérő idő-ablakkal jellemezhetők. Először a nyelvi inger kezdete után 200ms körül, a bal oldali agyfélteke elülső részére kiterjedő negatív potenciált észleltek, amely a lokális frázis-szerkezeti információk feldolgozásával volt kapcsolatos. A strukturálisan hibás mondatszerkezetek feldolgozásakor ez a terület maximálisan aktiválódott. Másodszor kétféle, egyaránt 400ms körüli, ám eltérő eloszlású negatív potenciált mértek: (a) a lexikai-szemantikai anomáliák- hibák által kiváltott negatív potenciált, mely az agykéreg hátulsó területein volt látható széles kiterjedésben, nemcsak a baloldalon, hanem a jobboldalon is; (b) ugyancsak a nyelvi inger kezdete után 400ms körül, egy bal oldali elülső területű negatív potenciált mértek, amely az igei argumentum szerkezeti információk, igei alkategorizációs információk feldolgozásával hozható kapcsolatba. Harmadszor, a nyelvi inger kezdete után 600-800 ms között pozitív potenciált mértek a középső és a hátulsó kérgi területeken, mindkét agyféltekén nagy kiterjedésben, amely valószínűleg a szerkezeti újraelemzés folyamatával függ össze. Ez akkor válik szükségessé, ha a felépített szerkezet és a lexikai-szemantikai információk összekapcsolása nem volt teljesen sikeres, például a mondat interpretációja nem egyértelmű. Az ún. "becsali" (garden path), mondatok feldolgozásakor történhet. (v.ö. Nevettek az árbocon a matrózok a fedélzeten). 2.2. Az eredmények azt jelzik, hogy a bal oldali elülső agykérgi területek elsősorban a szintaktikai szerkezet valós idejű kijelöléséért felelősek. A lexikai egységeket feldolgozó műveletek korlátozódása gyakran egybeesik a bal oldali hátulsó agyterületek sérülésével, míg az alkategorizációs információk feldolgozásában a baloldali elülső kérgi területek vesznek részt. 3.1. Az agrammatikus afáziásoknál gyakran mind a beszédprodukció, mind pedig a beszédértés egyidejűleg valamilyen módon károsodik, és ezeket a károsodásokat nyelvtani terminusokban lehet leírni. Számos kutató szerint a produkció és a megértés egyidejű zavara már magának a mentális nyelvtannak a közvetlen sérülését jelzi. Linebarger (1995) szerint ilyenkor a nyelvtan szintaktikai komponense veszik el. Friedmann-Grodzinsky (1997) szerint viszont a szintaktikai feldolgozás meghatározott almoduljának elvesztéséről van szó, melynek következtében például a szintaktikai összetevők mozgatása utáni nyomok törlődnek a szintaktikai reprezentációból.
Nyelvtan és Mentális Elemző Neurolingvisztikai Megközelítésben
67
A beszédprodukció és feldolgozás egyidejű deficitjére azonban más magyarázat is lehetséges. Az afáziások beszédintonációja gyakran erősen korlátozott, jellegzetesen monoton intonációt produkálnak. Nagel és Shapiro (1994) egészséges személyek és afáziások rögzített beszédét analizálva azt találta, hogy az afáziások nem produkálnak nyelvtani szempontból normál dallamot a mondatokon belüli „hosszabb tartományok”-ban, és nem produkálnak sem bizonyos időtartam jegyeket, sem szintaktikai pozíciókhoz társítandó kontrasztív nyomatékokat. A szerkezeti pozíciókhoz társított prozódia közreműködik annak meghatározásában, miképpen kapcsolódnak össze lexikai és szerkezeti kategóriák a mondatstruktúrában. A prozódiai információ valószínűleg nagyon korán, a kezdeti elemzés során felhasználásra kerül annak érdekében, hogy segítsen a mondatfeldolgozás során felmerülő csatolási kérdések eldöntésében, hogy a szerkezet feldolgozása során fellépő bizonytalanságokat megoldja. Nagel és Shapiro szerint az afáziások nem képesek a megfelelő időben felhasználni a prozódiai információt a mondatszerkezet feldolgozásában. 3.2. A magyar nyelvű afáziások a beszédprodukcióban kikerülik az erős nyomatékot hordozó fókuszt, a tagadott fókuszt és a kvantoros kifejezéseket. Helyettük a szintaktikai fában "lejjebb" helyezett, nem nyomatékos változókat produkálnak. Mivel csak késve képesek vagy egyáltalán nem képesek időben felhasználni a prozódiai információt a szerkezeti viszonylatok meghatározásában, ezért olykor hibás, töredékes szerkezet feldolgozásokat végeznek. A mondat megértésében pedig fennakadásokat, nehézségeket okozhat a fókusz interpretációja és a kvantoros kifejezés értelmezése: Adatok mondatismétlési tesztekből. A vizsgálati személy: parietális hypodensitas.
57 éves nő, sérülése: fronto-
a fel nem dolgozott információ elhagyása: Tagadó operátor törlése V: A vezetőt NEM idegesítette a zaj. A vezetőt idegesítette a zaj.
A feldolgozott információ korlátozott produkciója: lejjebb helyezés a szintaktikai fában: -- igetagadás képzése: V: A moziban “nem Péterrel beszélgettem. Péterrel ö…. Péterrel “nem beszélgettem.
-- a kérdőszó helyett hasonló változó lejjebb a szintaktikai fában: V: Kit láttál az utcán? ..Hogy az utcán ment valaki, az utcán.. az utcán mentél.
A fókusznyomatékot nem produkálja. Tárgy elhagyása: V: MARI hajtotta biciklit gyorsan és PÉTER [
].
Tehát .. mindenki hajtott gyorsan , Mari is meg Péter is.
4. Egészséges esetben a különféle agyi területeken tárolt nyelvtani reprezentációk, időzített sorrendben, aktiválhatók. Az éppen aktivált nyelvtani reprezentációkat a beszédprodukciót és a beszédfeldolgozást szervező valós idejű mentális programok, mint instrukciókat "olvassák el". A lokalizált agysérülések a nyelvi képesség valamely részrendszere, részfunkciója korlátozódásához
68
Nyelvtan és Mentális Elemző Neurolingvisztikai Megközelítésben
vezethetnek, a többi épen maradása mellett. Vagyis a nyelv és használata válhat szét funkcionális komponenseire. A dolgozatunkban tárgyalt adatokkal és összefüggésekkel azt kívántuk bemutatni, hogy a neurolingvisztikai vizsgálatok a nyelvtant olyan környezetben írják le, melyben a nyelvtan beágyazott az agy architektúrájába, interfész pontokon kapcsolódva az agy és az elme mentális programjaihoz. Ezáltal megnyílik az út a nyelvtan modellek neurológiai realitásának a kutatásához is.
Irodalom Friederici, A. D,.1995. The Time Course of Syntactic Activation during Language Processing: A Model Based on Neuropsychological and Neurophysiological Data, Brain and Language, Vol 50, 259-281. Hahne A. - Friederici A.D. 1999. Electrophysiological Evidence for Two Steps in Syntactic Analysis: Early Automatic and Late Controll Process. Journal of Cognitive Neuroscience 11:2, 194-205. Friedmann, N. -Grodzinsky, Y. 1997. Tense and Agreement in Agrammatic Production: Pruning the Syntactic Tree, Brain and Language, 56, 397-425. Hagiwara, H. 1995. The breakdown of functional categories and the economy of derivation. Brain and Language, 50. 92-116. Kolk, H. 1995. A Time-Based Approach to Agrammatic Production. Brain and Language 50. 282-303. Linebarger, M. C. 1995. Agrammatism as Evidence about Grammar. Brain and Language, 50. 52-91. Nagel, N., & Shapiro, L. P. 1994. Prosody and the processing of filler-gap sentences. Journal of Psycholinguistic Research. [Special Issue] Swinney D., - Zurif E., 1995. Syntactic Processing in Aphasia, Brain and Language, Vol 50, 225-239.
Semantic Bridging Effects in VP-Ellipsis
69
Semantic Bridging Effects in VP-Ellipsis Beáta Gyuris
Introduction The aim of this paper is to investigate the semantic processes underlying the interpretation of a certain subgroup of Hungarian sentences containing VP-ellipsis. The data and the analysis will give support to the claim made by Bánréti (1999, 2000) and Bartos (to appear), according to which the mental lexicon consists of sublexicons with their own, sometimes independent, phonological, syntactic and semantic principles which are not always extendable to the other sublexicons and to structural complexes containing items from more than one sublexicons. The study will also contribute to the characterization of differences between the linguistic processes operating in backwards versus forward VP-ellipsis, as argued by Wilder (1997), Bánréti (1999, 2000) and Bartos (to appear). The Hungarian data to be presented and analysed exemplifies a less frequently studied subtype of VP ellipsis, a case where the antecedent and the ellipsis site contain material which cannot be equivalent to each other syntactically, regardless of which level of syntax (LF, surface structure, etc.) is considered, like, for example, in (1) below, where the intended content of the ellipsis site is crossed out3:
(1)
Vili
szeretne
Marival
Bill
like-cond-3sg Mari-with
[VP táncolni/ Vilivel dance-inf
táncolni,
de
Mari
nem szeretne
dance-inf
but
Mari
not
like-cond-3sg
táncolni]. Bill-with
dance-inf
‘Bill would like to dance with Mary but Mary wouldn’t like to [dance/dance with Bill].’
The necessary non-identity between the ellipsis site and the antecedent in the case of (1) can be proved by the ill-formedness of (2) below, where the same syntactic constituents appear in the antecedent and at the ellipsis site:
(2)
* szeretne
Vili
Bill like-cond-3sg [VP Mari-with
szeretne
Marival
like-cond-3sg Mary-with Marival
táncolni,
de
Mari
nem
dance-inf
but
Mari
not
táncolni].
dance-inf
‘Bill would like to dance with Mary but Mary wouldn’t like to [dance with Mary]’.
As opposed to accounts of the above and related phenomena (found in, for example, Asher (1993), Hardt (1993), etc.), which consider the interpretation of VP-ellipsis with syntactic nonidentity as belonging to the domain of pragmatics, we are going to argue in this paper that a large portion of the cases manifesting lack of syntactic identity between the antecedent and the elided 3
In what follows, acceptability judgments for sentences with ellipsis will also take into account the assumed content of the ellipsis site, where indicated.
Semantic Bridging Effects in VP-Ellipsis
70
material can in fact be accounted for on the basis of purely lexical semantic principles, which can also give us an insight into the mental representation of individual lexical items.
A preliminary overview of the data In this paper, we will concentrate only on instances of VP ellipsis occurring in coordinate structures. By forward ellipsis we refer to those cases where the ellipsis site appears in a non-initial conjunct, and it is preceded by its antecedent. Conversely, the term backwards ellipsis will be used to refer to those cases where the ellipsis site appears in a non-final conjunct, and it is followed by its antecedent. Sentence (3) below illustrates a case of forward ellipsis which is non-interpretable if the elided material is considered to be identical to its antecedent. It, however, can be made acceptable, as (4) shows, if the ellipsis site is taken to have an interpretation non-identical to, but semantically related to that of the antecedent in such a way that the meanings of the clauses containing the antecedent and the ellipsis site can be considered synonymous.
(3)*
Viki
és
Gabi
szeretnének
összeházasodni, de
Gabi
nem
Viki
and
Gabi
like-cond-3pl
marry-inf
Gabi
not
mer
[VP összeházasodni], mert
dare-3sg marry-inf
because
but
az
apja
utálja
the
father-3sgposs hate-3sg
Vikit. Viki-acc
* ‘Viki and Gabi would like to get married, but Gabi does not dare to [marry], since her father hates Viki.’
(4)
Viki és
Gabi
szeretnének
összeházasodni,
de
Gabi
nem
Viki and
Gabi
like-cond-3pl
marry-inf
but
Gabi
not
mer
[VP összeházasodni
Vikivel],
mert
dare3-sg
marry-inf
Viki-with
because the
az
apja
utálja
Vikit.
father-3sgposs
hate-3sg Viki-acc
‘Viki and Gabi would like to get married, but Gabi does not dare to [marry Viki], since her father hates Viki.’
Similarly, in the case of (1) above, repeated here as (5), those cases of ellipsis reconstruction lead to felicitous interpretations where the meaning of the clause contianing the ellipsis site is either entailed by (as in Mari nem szeretne táncolni ‘Mary would not like to dance’) or synonymous with (as in Mari nem szeretne Vilivel táncolni ‘Mary would not like to dance with Bill’) the clause containing the antecedent:
(5)
Vili
szeretne
Marival
Bill
like-cond-3sg Mari-with
táncolni,
de
dance-inf but
Mari
nem
szeretne
Mari
not
like-cond-3sg
Semantic Bridging Effects in VP-Ellipsis
71
[VP táncolni/ dance-inf
Vilivel
táncolni].
Bill-with
dance-inf
‘Bill would like to dance with Mary but Mary wouldn’t like to [dance/dance with Bill].’
As opposed to the instances of forward ellipsis illustrated above, which tolerate lack of syntactic identity in the case of semantic equivalence or entailment between the clauses containing the antecedent and the consequent, backwards ellipsis seems to be based on full phonological identity between the antecedent and the elided material, since the backwards counterparts of (4) and (5) are infelicitous, as (6) and (7) illustrate:
(6)
* Mari
nem szeretne
Mary
not
[VP Vilivel
like-cond-3sg Bill-with
szeretne
Marival
táncolni.
like-cond-3sg
Mary-with
dance-inf
táncolni/táncolni],
de
Vili
dance-inf/dance-inf
but
Bill
‘Mary would not like to [dance with Bill/dance], but Bill would like to dance with Mary.’
(7)
* Gabi nem Gabi not
mer
[VP összeházasodni
Vikivel],
bár
dare-3sg
marry-inf
Viki-with
though Viki
szeretnének
összeházasodni.
like-cond-3pl
marry-inf
Viki
és
Gabi
and
Gabi
‘Gabi doesn’t dare [to marry Viki], although Viki and Gabi would like to marry.’ Incidentally, the elliptical strings themselves cannot be made felicitous at all, even under a different construal of the elided VP. (8) and (9) below illustrate that an interpretation according to which the ellipsis site contains material identical to its antecedent also fails, just like the corresponding interpretations of (2) and (3) do. (8) is ill-formed both due to the irreflexivity of the predicate expressed by the verb táncol ‘dance’ and Principle C of the Binding Theory, while (9) fails since the only argument of the verb összeházasodik ‘marry’ denotes an individual an not a plural entity, as required by the semantics of the verb (to be discussed more throroughly in Section 4.3) :
(8)
* Mari Mary
nem
szeretne
[VP Marival
táncolni],
de
Vili
szeretne
not
like-cond-3sg Mary-with
dance-inf
but
Bill
like-cond-3sg
Marival
táncolni.
Mary-with
dance-inf
‘Mary would not like to [dance with Mary], but Bill would like to dance with Mary.’
Semantic Bridging Effects in VP-Ellipsis
72
(9)
* Gabi Gabi
nem
mer
[VP összeházasodni], bár
not
dare-3sg
marry-inf
szeretnének
összeházasodni.
like-cond-3pl
marry-inf
Viki és
though Viki and
Gabi Gabi
‘Gabi doesn’t dare [to marry], although Viki and Gabi would like to marry.’
The above examples indicate, on the one hand, that VP ellipsis can be possible even if syntactic identity is ruled out between the content of the ellipsis site and its antecedent, while, on the other hand, they argue for distinguishing between the processes and the licensing mechanisms operating in the case of backwards versus forward ellipsis. The data seem to support the claim made by Wilder (1997) and Bartos (to appear) that backwards ellipsis is licensed under phonological identity, while the licensing mechanism of forward ellipsis allows for certain degrees of mismatch between antecedent and elided material. (A detailed discussion about the allowed degrees of dissimilarity between antecedent and ellipsis site is found in Bartos (to appear) and Bartos & Gyuris (2000)). This freedom, however, is not without its limits, since, while in (10)-(11) we could in theory successfully infer the contents of the ellipsis site on the basis of the „synonymy-strategy” or the „entailmentstrategy” mentioned above, they are markedly worse than (2)-(3), if not downright rejectable.
(10)
?? Iván
táncolna
Mártával,
de
Ivan
dance-cond Márta-with but
Márta nem [VP táncolna/táncolna Márta not
Ivánnal].
dance-cond/dance-cond Ivan-with
?? ‘Ivan would dance with Márta, but Márta not.’
(11) ?? Péter Peter
szeretne
táncolni
Marival,
de
like-cond
dance-inf Mary-with but
Mari
nem [VP szeretne táncolni
Mary
not like-cond
dance-inf
Péterrel].
Peter-with ?? ‘Peter would have liked to dance with Mary, but Mary not.’
The last two examples illustate that the interpretation of the site of forward VP-ellipsis, although less constrained than backwards ellipsis, cannot be based only on the availability of a feasible semantic relation connecting the antecedent and the ellipsis site, but has to obey certain constraints of the grammar as well, which are going to be discussed below in Section 4. The structure of the rest of the paper is as follows. In Section 3 we will summarize and point out the difficulties with existing treatments of the phenomena of semantic bridging in ellipsis illustrated above. In Section 4 will show, following Bartos (to appear) and Bartos & Gyuris (2000) that, in order to make the theory more constrained and to incorporate the restrictions imposed by the grammar on the interpretation of VP-ellipsis, the semantic relations making possible the interpretation of sentences with ellipsis have to be encoded in the lexicon, and not relegated to the LF or semantic component of the grammar. This view will naturally have some repercussions on the structure of the lexicon, which are discussed in Section 5. The paper ends with the conclusions in Section 6.
Semantic Bridging Effects in VP-Ellipsis
73
Semantic and pragmatic accounts of VP-ellipsis interpretation Traditionally, investigations of the relation between the antecedent and the elided material in VP-ellipsis (as well as other types of ellipsis) concentrated on finding the level of syntax where the above mentioned two constituents could be found identical to each other (e.g., Sag 1976, Williams 1977, Lappin 1996, Tomioka 1997, etc.). Webber (1979) was the first to call attention to examples of VP-ellipsis like those reproduced here as (12) and (13) (Webber’s exx. (67) and (68)), where syntactic identity between the antecedent and target of ellipsis is clearly impossible: (12)
Irv and Martha wanted to dance together, but Martha’s mother said that she couldn’t ∅. ∅ = dance with Irv
(13) Irv and Martha wanted to dance with each other, but Martha’s mother said that she couldn’t ∅. ∅ = dance with Irv Webber (1979) argues for allowing inferences to determine the appropriate content of the ellipsis site. For example, the reasoning procedure giving the interpretation of the elided material in (12) and (13) would be the following. If a reciprocal predicate P applies to two arguments a and b, then the predicate has to apply to any two arguments one of which is a or b, while the other is represented by a variable. This rule is formalized by Webber as follows:
