Neural correlates of Dutch Verb Second in speech production

Dutch speakers with agrammatic Broca's aphasia are known to have problems with the production of finite verbs in main clauses. This performance pattern has been accounted for in terms of the specific syntactic complexity of the Dutch main clause structure, which requires an extra syntactic operation (Verb Second), relative to the basic Subject-Object-Verb order surfacing in Dutch subordinate clauses. We report an fMRI study into the question whether this syntactic complexity is reflected in increased brain activation correlated with the production of Dutch main clause word order, in speakers without language impairment. Nineteen healthy subjects performed a covert sentence completion task, during which main and subordinate clauses were alternately elicited in a block design. Results show a left middle to superior frontal cluster of activation correlated to production of Verb-Second over Verb-Final clauses, with no activation in the opposite contrast. This activation pattern is counter to what might be expected from the frequency distribution of main and subordinate clauses. We conclude that the Verb-Second deviation from the basic Dutch SOV word order costs extra neural resources and that this also underlies the agrammatic problems with the production of finite verbs in Dutch main clauses.     

A comparison of syntax in young stutterers and nonstutterers

This study compares the syntactic structure of the spontaneous speech of a small group of stutterers and nonstutterers, using a method of constituent analysis. Speech samples were taped during play sessions with subjects, and the tapes were then transcribed and analyzed according to preselected constituent criteria. The stutterers were in the early stages of stuttering and had been diagnosed as stutterers by experienced clinicians. The method of analysis proved to be highly reliable. Differences were found in the number of complete clauses, the number of complex sentences, and in clause types between the two groups.     

Syntactic influences on stuttering in young child stutterers

This study examined the location and rate of stuttering in the spontaneous speech of nine young stutterers (4.0–6.6 yr) in relation to certain aspects of syntax. It was designed to answer the following questions: Is there more stuttering at clause onset (boundary) than at other points in the clause? Does the type of clause influence rate of stuttering? Is there more stuttering on complex than on simple sentences? The syntactic analysis defined 10 clause types (seven pertaining to complex sentences and three pertaining to simple sentences); clause boundaries (taking into account “filler” words occuring in such positions); and hierarchical constituent structure within sentences. Stuttering was found with significantly greater frequency at clause boundaries than at internal (nonboundary) positions of clauses. This was apparent for nine of the 10 clause types, the exception being complement clauses. The word “and” at the beginning of simple and complex sentences provoked a high rate of stuttering. The hierarchical structure within the clause did not influence the location of stuttering, and sentence complexity was not a factor in the rate of stuttering.     

Speech Rate and Syntactic Complexity as Multiplicative Factors in Speech Comprehension by Young and Older Adults

An experiment is reported in which young and older adults heard short English sentences that differed in syntactic complexity and speech rate. The syntactic contrast pitted center-embedded sentences with a subject-relative clause against sentences with center-embedded object-relative clauses. Speech rate was varied using computer time-compression of the speech signal. Both young and older adults showed poorer comprehension accuracy for the more complex object-relative clause sentences than subject-relative sentences, with an age difference appearing only when sentences were presented at a very rapid rate. By contrast to accuracy scores, older adults took longer than the young adults to give their comprehension responses at all speech rates tested, with this age difference amplified by both speech rate and syntactic complexity.     

Lexical, morphological, and syntactic aspects of verb production in agrammatic aphasics

Agrammatic aphasics do not exhibit a normal pattern of verb production; their spontaneous speech is said to lack verbs, and the verbs that are produced lack inflection. The current article focuses on the lexical, morphological, and syntactic aspects of verbs in spontaneous speech of a group of Dutch agrammatic speakers. Dutch is a so-called verb-second language in which the finite verb in the matrix clause is in the second position and nonfinite verbs are in the final position. The analysis shows that agrammatic speakers are sensitive to this relation; they virtually never produce finite verbs in the final clause position or nonfinite verbs in the second position. Nevertheless, they produce significantly fewer finite clauses than do non-brain-damaged speakers. The diversity of the lexical verbs in spontaneous speech is also lower than in non-brain-damaged speakers, but this is due to less variation in the finite lexical verbs. Hence, it is suggested that the problems with verbs in Dutch agrammatic spontaneous speech are restricted to finite lexical verbs. In an experiment, it was evaluated whether these problems with finite lexical verbs are caused by a morphological deficit or a syntactic deficit. The data show that a syntactic deficit is more likely; Dutch agrammatic speakers produce finite verbs in the base-generated position (i.e., in the embedded clause) significantly better than finite verbs that have been moved to the second position (i.e., in the matrix clause). From these data, the authors conclude that in Dutch, a verb-second language, agrammatic aphasics demonstrate specific problems with moved finite verbs, although they are perfectly aware of the relation between verb position and verb finiteness. This syntactic problem affects not only the proportion of finite verbs but also the diversity of the verbs and, hence, communicative contents.     

Syntactic structure modifies attention during speech perception and recognition

The present paper demonstrates the interaction of syntactic structure and speech perception with a response task which minimizes the effects of memory: reaction time (RT) to clicks during sentences. (1) In 12-word unfamiliar sentences each with two clauses, RT is relatively slow overall to clicks located at the end of the first clause but decreases as a function of clause length. Clicks at the beginning of the second clause are not affected by length of the preceding clause. (2) In familiar sentences, RT is relatively fast to clicks located at the end of a clause while RT to clicks at the beginning of clauses is relatively unaffected by familiarity. (3) RT is not fastest overall to clicks located between clauses either in novel or familiar sentences. (4) As in previous studies, the subject's subsequent judegment of the location of the click tone are towards the clause break. (5) We could find no systematic interaction between RT and subjective click location. Findings (1) to (3) are consistent with the view that perceptual processing alternates between attending to all external stimuli and developing an internal representation of the stimuli. Finding (3) is in conflict with an “information channel” view of immediate attention to speech, which would predict high sensory attention to non-speech stimuli between clauses. However, findings (4) and (5) indicate that the channel view of perception may be correct for that perceptual processing which occurs after the immediate organization of the speech stimulus into major segments.     

A note on temporal relations between language and gestures

The initiation of the spontaneous gestures of Wernicke's aphasics was analyzed in relation to shifts in semantic content between the syntactic boundaries of main clauses and embedded clauses. Gestures proved more likely to arise at the initial boundaries of embedded clauses when these were semantically discontinuous with the main clause than when these were semantically related to the main clause. Spontaneous gestures may signal underlying shifts in semantic intention, thereby reflecting the difficulties encountered by Wernicke's aphasics in maintaining a coherent stream of thought across syntactic boundaries.     

Selective Retention of Information about the Superficial Form of Text: Ellipses W ith Antecedents in Main and Subordinate Clauses

Elliptical verb phrases must be interpreted indirectly, using a representation of the surface form of nearby (usually preceding) text. We used this fact to demonstrate the different availability of superficial representations of the two clauses in main-subordinate pairs. The acceptability of a later ellipsis was reduced when it took its meaning from a main clause that was followed by a subordinate clause, as compared with other combinations. In addition, positive acceptability judgements were made more quickly (1) when the antecedent clause was subordinate, rather than main, suggesting that the superficial form of a subordinate clause is more important, and (2) when the antecedent was in the immediately preceding clause, rather than two clauses back. These results support the idea that the surface form of subordinate clauses is selectively retained until the corresponding main clause has been read, but the surface form of a main clause is not retained after it has been interpreted.     

Does Structural Complexity Necessarily Imply Processing Difficulty?

Our goal is to establish a link between the time needed to plan a sentence containing an embedded clause and the structure of this sentence. Contrary to a traditional monolithic conception of subordination, three types of embeddings were considered, depending on their degree of syntactic integration: subcategorized, modifier and pseudo-embedded clauses. We hypothesized that in the case of subcategorization, fewer pauses should occur between the matrix and the subordinate clause since the latter is required by the lexical properties of verbs. By contrast, pseudo-embedded clauses are the less integrated. Hence, they should exhibit planning characteristics similar to the ones of simple sentences, the matrix clause and the subordinate clauses being planned in two steps. Twenty texts produced by French speaking adults were recorded. Pauses were characterized according to their duration and position. Globally, both predictions were confirmed. We conclude that supposedly complex sentences are not necessarily difficult to process.     

Syntactic breakdown and recovery of clausal structure in agrammatism

We studied the recovery of clause structures in four agrammatic patients by performing a longitudinal analysis of their spontaneous production. We classified their utterances in terms of legitimacy of the syntactic structure and rate of subordination. The results show that, initially, patients omit verbs, avoid subordination, just employ present tense, and substitute finite verbs with infinitives. During the recovery they start employing other tenses and subordinate clauses and reduce the use of infinitives. Data suggest a mixed syntactic and morphological origin of the impairment. Assuming that phrasal representations are built bottom-up from an array of lexical items, we propose that syntactic structures recover stepwise, with the lower portion of the syntactic tree becoming accessible before higher portions. We claim that, despite superficial similarities between agrammatic and children's speech, e.g., use of infinitives instead of finite verbs, a unified account is not viable.     

Significance of pauses for speech perception

Pauses can be used to facilitate certain operations involved in the production and in the perception of speech. In the case of speech perception, pauses have been found to improve the accuracy of detection and the recall of lists of digits and letters. The aim of the present experiments was to examine the effects of pause time on the perception of sentences. In experiment I, a semantic categorization task was used and in experiment II a sentence recall task. The results indicated that in sentences containing pauses between clauses, words were categorized more rapidly (experiment I) and propositions were recalled more accurately (experiment II) than in sentences containing pauses, within the clause. The results are interpreted in the context of existing models of speech processing, and the significane of pause time for cognitive activity is discussed.     

Dissociable patterns of brain activity during comprehension of rapid and syntactically complex speech: evidence from fMRI

Sentence comprehension is a complex task that involves both language-specific processing components and general cognitive resources. Comprehension can be made more difficult by increasing the syntactic complexity or the presentation rate of a sentence, but it is unclear whether the same neural mechanism underlies both of these effects. In the current study, we used event-related functional magnetic resonance imaging (fMRI) to monitor neural activity while participants heard sentences containing a subject-relative or object-relative center-embedded clause presented at three different speech rates. Syntactically complex object-relative sentences activated left inferior frontal cortex across presentation rates, whereas sentences presented at a rapid rate recruited frontal brain regions such as anterior cingulate and premotor cortex, regardless of syntactic complexity. These results suggest that dissociable components of a large-scale neural network support the processing of syntactic complexity and speech presented at a rapid rate during auditory sentence processing.     

The development of complex sentence processing strategies

Children aged 3, 4, and 5 years and adults heard sentences with clauses connected by after, and, or before, saw a picture, and indicated whether or not the picture matched one of the events of the sentence. Response times were taken as a measure of immediate accessibility to the meaning of the clause that the picture was about. Temporal organization of sentence meanings was dominant in 3-year-olds and adults, but not in 4- or 5-year-olds. The 3-year-olds and especially the adults processed and-sentences as implicitly temporal. The results for 4- and 5-year-olds are interpreted as indicating experimentation with alternate strategies for organizing sentences based on the structural/presuppositional properties of clauses.     

Effect of sentence structure on stuttering

The elicited speech of 20 adult male stutterers was analyzed to determine the effect of the number, type, and location of relative clause structures on the frequency of stuttering. The selected structures were identified on the basis of transformational grammar. The findings indicate that the frequency of stuttering increases significantly with an increase in the number of relative clauses included in a matrix sentence structure. The results also indicate that the more severe the stuttering is, the more the stutterer is likely to be affected by this variable. Trends toward more frequent stuttering in the postverbal relative clause and the adjectival form of the relative clause were observed.     

The production of Turkish relative clauses in agrammatism: Verb inflection and constituent order

This study presents results from a sentence completion test that examines the production of finite main clauses and non-finite relative clauses in Turkish agrammatic speech. In main clauses, the verb is finite and all its constituents are in their base positions. In relative clauses, the verb is a participle and the NP undergoes overt movement to an A-bar position. The results show that non-finite relative clauses with overt movement as such are more difficult to produce than finite main clauses with a base order. The findings are discussed with respect to several hypotheses on finite verbs and syntactic complexity. The conclusion is that Turkish agrammatic speakers have more problems in producing structurally derived clauses and the production of verbs is influenced by linguistic factors such as the overt movement of the NP.     

Relatives Children Say

In an experiment designed to elicit restrictive relatives clauses, 28 children ranging in age from 2:2 to 3:10 provided a corpus of communicatively appropriate relative clauses. In evaluating this corpus, we found that most children produced mostly adult relative clauses most of the time. Detailed study of these utterances uncovered a few error patterns, which we analyzed in light of several considerations (e.g., the overall frequency of an error type, its distribution across children and items, its relation to the construction under study, and the similarity of the error to what children do elsewhere). Only one error pattern, namely some children's production of inappropriate relative pronouns, is argued to reflect a systematic feature of language development. We conclude that children's ability to represent the syntactic structure of the embedded clause is on target very early.     

汉语主、宾关系从句加工难度及其核心名词生命性效应

采用眼动追踪实验技术,考查了核心名词生命性取向对汉语主、宾关系从句加工难度调节效应。结果显示:(1)核心名词生命性格局对汉语主、宾关系从句的加工难度有着显著调节作用,具体表现为:当主、从句中的核心名词为"生命性-非生命性"格局时,在主句核心名词、核心动词位置,宾语关系从句加工较为容易;当主、从句中的核心名词为"非生命性-生命性"格局时,在上述位置,两种关系从句加工难度差异不显著;(2)汉语主、宾关系从句加工中核心名词生命性效应主要发生在语义信息提取、论元关系建构阶段,体现出汉语语言的特异性。上述结果支持了题元切适性理论。     

Detection of a nonlinguistic stimulus is poorest at the end of a clause

Subjects detected a brief near-threshold tone while encoding two-clause sentences for later report. The objective tone locations were at the end of the first clause, at the beginning of the second clause, or in the clause boundary. The effects of intensity variations of the speech signal were assessed by having subjects detect the tones in the same speech stimuli played backward. Tones at the end of a clause are relatively harder to detect than in other positions, comparing forward and backward speech. This supports the view that listeners are preoccupied with internal processes at the end of a clause.     

The processing of subject and object relative clauses in Spanish: An eye-tracking study

A normative study and an eye-tracking experiment investigated the influence of animacy on the processing of subject and object relative clauses in Spanish. The results showed that object relative clauses caused more difficulty than subject relative clauses, but that animacy modulated this preference. The overall pattern was similar to findings in other languages. However, because of the syntactic characteristics of Spanish relative clauses, the results give novel insights into the processing mechanisms that underlie relative clause processing.