The effect of syntactic structure upon speech initiation times of stuttering and nonstuttering speakers

Past research has shown that adults who stutter tend to be slower than adults who do not stutter at initiating various speech-like movements, nonsense syllables, words, short phrases, and simple sentences. The present study sought to extend this research by examining the effect that syntactic structure has upon stutterers' and nonstutterers' ability to initiate sentences. Eleven persons who stutter (mean age=22.2 years) and 11 nonstuttering controls (mean age=23.3 years) read, rehearsed, and then reproduced a series of 96 sentences within a simple reaction time paradigm. The sentences were presented in four blocks of 24 sentences, and each block contained one version of each of the 24 base sentences. Versions of the base sentences varied, from simple to complex, along four levels of syntactic complexity. Results indicated that speech initiation times (SITs) were significantly longer for participants who stutter than they were for nonstuttering controls for three of the four sentence types. There was no significant difference in SITs across the four sentence types for either group. Among the stuttering participants, there was no significant correlation between stuttering severity and overall initiation time for the sentences. Consistent with other studies, the present findings suggest that persons who stutter are slower than persons who do not stutter at planning and/or initiating motor movements associated with speech production. EDUCATIONAL OBJECTIVES: The reader will be able to (1). describe how persons who stutter typically perform during various reaction time tasks, (2). explain the rationale for examining the effect of syntactic complexity upon speech initiation time, (3). discuss how the speech initiation times of persons who stutter compare to those of persons who do not stutter during the production of various types of sentences, (4). identify future research needs in this area.     

‘I stumble... in my speech: Like a hobbled... horse... hops...’ — The nature and length of pauses in the reading of aphasics

Summary Fifteen mildly affected aphasic subjects were given the task of reading 21 sentences. The words of the sentences (apart from the articles) were controlled according to part of speech, length, and frequency of occurrence. It was predicted that the complexity of the grammatical function of the nouns, adjectives, and verbs investigated would determine the length of the pauses preceding the part of speech in question. The relative complexity of the syntactic function was determined by the number of valences according to the theory of dependence grammar. The results obtained supported the model of dependence grammar in that, of the content words, verbs were preceded by the longest pauses and adjectives by the shortest. The most surprising result was the finding that the pauses before the second article were even longer than those before the verb. It was suggested that these pauses be interpreted as following the verb rather than preceding the article. With respect to the nature of these pauses, a variety of classifications was discussed. It was proposed that these latencies be interpreted as juncture pauses, made for the sake of the listener in normal readers, changed into hesitation pauses, made for the sake of the reader in aphasics.     

Syntactic analysis in sentence comprehension: Effects of dependency types and grammatical constraints

This paper presents three experiments on the parsing of Italian wh-questions that manipulate the wh-type (whovs. which-N)and the whextraction site (main clause, dependent clause with or without complementizer). The aim of these manipulations is to see whether the parser is sensitive to the type of dependencies being processed and whether the processing effects can be explained by a unique processing principle, the minimal chain principle (MCP; De Vincenzi, 1991). The results show that the parser, following the MCP, prefers structures with fewer and less complex chains. In particular: (1) There is a processing advantage for the wh-subject extractions, the structures with less complex chains; (2) there is a processing dissociation between the whoand which questions; (3) the parser respects the principle that governs the well-formedness of the empty categories (ECP).     

From metasemantics to analyticity

In this paper, I argue from a metasemantic principle to the existence of analytic sentences. According to the metasemantic principle, an external feature is relevant to determining which concept one expresses with an expression only if one is disposed to treat this feature as relevant. This entails that if one isn’t disposed to treat external features as relevant to determining which concept one expresses, and one still expresses a given concept, then something other than external features must determine that one does. I argue that, in such cases, what determines that one expresses the concept also puts one in a position to know that certain sentences are true—these sentences are thus analytic relative to this determination basis. Finally, I argue that there are such cases: some sentences are analytic relative to what determines that we express certain key concepts, and these sentences include ones that have always been thought to be the best candidates for being analytic, namely, stipulative truths, and first principles of mathematics.     

Children's use of semantic analysis in the interpretation of missing subjects: Further evidence against the MDP

Preschool and many older children often have difficulty understanding who carries out the complement action (e.g., to go in sentences such asMary promised John to go; this is so, even though they easily understand this information in sentences such asJohn told Mary to go. C. Chomsky (1969) proposed that children's errors arise from the overgeneral application of a purely structural Minimal Distance Principle. Maratsos (1974), however, hypothesized that children err by overgeneralizing a different principle which he called the Semantic Role Principle. According to this principle, the Goal-Recipient of the spoken message, not the closest noun phrase, is understood as the person who carries out the act referred to by the infinitival complement. The two studies reported here were designed to determine which of these principles children use. Preschool children were taught to understand a specially designed novel construction. The children then acted out sentences containing related but novel uses of the construction such that they would respond differentially according to which interpretive principle they used. The results strongly favored the Semantic Role Principle, rather than the MDP described by Chomsky (1969), or a related, more complex MDP described by Rosenbaum (1967). It is further discussed how children's formulation of the Semantic Role Principle, rather than the MDP, might arise from their prior analyses of related constructions, such as the imperative construction, rather than following from an innate preference, as suggested in Maratsos (1974).This research was supported by the NICHD under Grant #5 R01 HD09112-02 given to M. P. Maratsos.     

Pauses and syntax in American sign language

Research on spoken languages has shown that the durations of silent pauses in a sentence are strongly related to the syntactic structure of the sentence. A similar analysis of the pauses (holds) in a passage in American Sign Language reveals that sequences of signs are also interspersed with holds of different lengths: long holds appear to indicate the ends of sentences; shorter holds, the break between two conjoined sentences; and the shortest holds, breaks between internal constituents. Thus, pausal analysis is a guide to parsing sentences in ASL.     

Some observations on the universality of the late-closure strategy

Two questionnaire studies and a reading time experiment investigated the application of the late-closure principle in Italian, a Romance language which contrasts with English with respect to several linguistic properties. All the studies addressed interpretation preferences in sentences containing a complex NP followed by a relative clause (e.g....the son of the woman who arrived yesterday...). While the questionnaires investigated final preferences, the reading time experiment addressed also the principle governing the initial attachment of a relative clause to a complex NP. Furthermore, through a manipulation of the type of preposition within the complex NP, we investigated the role of the thematic structure of the complex NP in initial and final parsing. The results showed that the late-closure principle applies in Italian to the initial parsing without being affected by the thematic structure of the complex NP. Final interpretation instead shows an effect of pragmatic preference and an effect of thematic structure on syntactic revisions. The results are discussed in terms of a parsing model that adopts syntactic parsing strategies and makes modular use of linguistic information. Some implications for the relationship between syntactic theories and the human parser are also addressed.     

Syntactic structure and the garden path

The experiment investigated locally ambiguous English sentences containing “complement” verbs such as believe, which can be followed either by a direct object or by a complement clause. These two sentence types were compared with unambiguous sentences in which the complement clause was introduced by the word that. Subjects processed numerous examples of these sentences in a word-by-word self-paced reading task. At the disambiguation point after the ambiguous noun phrase, longer reading times were obtained for reduced complement constructions compared with direct object sentences. Such an effect has been attributed to the operation of the parsing principle Minimal Attachment (Frazier and Rayner, 1982). This principle predicts that subjects assume falsely that the noun phrase after the complement verb in the reduced complement constructions is the direct object, resulting in the need for subsequent structural reanalysis. However, longer times in the disambiguating zone were also found for the unambiguous that complements. Thus, the complexity difference seems not to represent “garden-pathing” as a result of the operation of Minimal Attachment, but may instead reflect the extra complexity caused by having to handle two sets of clausal relations instead of just one.     

Learning individual talkers' structural preferences

Listeners are often capable of adjusting to the variability contained in individual talkers' (speakers') speech. The vast majority of findings on talker adaptation are concerned with learning the contingency between phonological characteristics and talker identity. In contrast, the present study investigates representations at a more abstract level - the contingency between syntactic attachment style and talker identity. In a 'visual-world' experiment, participants were exposed to semi-realistic scenes depicting several objects (e.g., an adult man, a young girl, a motorbike, a carousel, and other objects) accompanied by a spoken sentence with a structurally ambiguous relative clause (e.g., 'The uncle of the girl who will ride the motorbike/carousel is from France.' In the context of the scene, 'motorbike' suggested the uncle as the agent of the riding, whereas 'carousel' suggested the girl as the agent). For half the experimental items, one version of the sentence was read by one talker, who always uttered sentences that resolved, pragmatically, to the high attachment (the uncle as the agent), and the other by another talker, who always uttered sentences resolving to the low attachment (the girl as the agent). For the other half of the experimental items, both versions were read by a third talker who produced both high and low attachments. It was found that, after exposure to these stimuli, and for new sentences not heard previously, participants learnt to anticipate the 'appropriate' attachment depending on talker identity (with no attachment preference for the talker who produced both attachment types). The data suggest that listeners can learn the relationship between talker identity and abstract, structural, properties of their speech, and that syntactic attachment decisions in comprehension can reflect sensitivity to talker-specific syntactic style.     

From exemplar to grammar: a probabilistic analogy-based model of language learning

While rules and exemplars are usually viewed as opposites, this paper argues that they form end points of the same distribution. By representing both rules and exemplars as (partial) trees, we can take into account the fluid middle ground between the two extremes. This insight is the starting point for a new theory of language learning that is based on the following idea: If a language learner does not know which phrase-structure trees should be assigned to initial sentences, s/he allows (implicitly) for all possible trees and lets linguistic experience decide which is the "best" tree for each sentence. The best tree is obtained by maximizing "structural analogy" between a sentence and previous sentences, which is formalized by the most probable shortest combination of subtrees from all trees of previous sentences. Corpus-based experiments with this model on the Penn Treebank and the Childes database indicate that it can learn both exemplar-based and rule-based aspects of language, ranging from phrasal verbs to auxiliary fronting. By having learned the syntactic structures of sentences, we have also learned the grammar implicit in these structures, which can in turn be used to produce new sentences. We show that our model mimicks children's language development from item-based constructions to abstract constructions, and that the model can simulate some of the errors made by children in producing complex questions.     

The Dependence of the form of the Pursuitmeter Learning Function on the Length of the Inter-Practice Rests: II. Theoretical

Three hypotheses derived from an explanation sketch of the ability of some individuals to understand self-embedded (SE) sentences with two embeddings involving Syllogistic reasoning ability were tested with positive results. The data indicate that those individuals who can understand SE sentences with two embeddings will be better able to reason with the use of the Syllogistic form than those who cannot, that those individuals who can reason with the use of the Syllogistic form will be able to understand SE sentences with two embeddings, and that those individuals who cannot reason with the use of the Syllogistic form will not be able to understand SE sentences with two embeddings.     

The identification of structural components of an unknown language

Adult subjects attempted to identify structures (words and constituents) in sentences of a language they did not know. They heard each sentence twice-once with a pause interrupting a structural component and once with a pause separating different structural components. They were asked to choose the version that sounded more natural. An experimental group of subjects who had been previously exposed to a spoken passage in the same language as the test sentences was more successful in identifying structures of the sentences than was the control group with previous exposure to another language. This result was interpreted as demonstrating that language structure may be partially acquired during a brief exposure without reliance on meaning. It was also noted that the experimental group identified constituents more accurately than words. This result suggested that constituents, more than words, function as acquisitional units of language.     

Vowel duration in stutterers participating in precision fluency shaping

The purpose of this study was to determine the extent to which stutters manipulate vowel duration to achieve fluency after participating in Precision Fluency Shaping. Nine stutterers who read an all-voiced sentence fluently before and after therapy were selected for study. Wide-band spectrograms were made of the initial phrase of the sentences, and vowel durations were computed. Results indicated that extended vowel durations were characteristic of the fluency of stutterers posttherapy. The subject that had the highest rate of disfluency after therapy also had the shortest vowel durations. Clinical implications concerning the importance of speech rate during carryover practice are made.     

Syntactic complexity and elaborative processing

Memory for sentences as a function of the syntactic complexity of the sentences was examined. Sentence complexity was varied through a manipulation that involved presenting sentences in either self-embedded forms or more standard forms. Subjects performed an incidental semantic orienting task on a set of sentences varying in complexity and were subsequently tested for their recognition memory of the sentences. In Experiment 1, subjects were tested for their memory of both surface characteristics and meaning of the sentences. There were no differences caused by sentence complexity for memory for meaning. Memory for surface structure, however, was a function of sentence complexity such that there was better memory for the more complex sentences. Experiment 2 replicated the finding that the more complex sentences produced better recognition memory for surface structure. The results are interpreted within a framework that suggests that increased syntactic complexity produces more elaboration, which in turn produces better memory.     

The effect of semantic plausibility on sentence comprehension in aphasia

Tested were 50 aphasic patients (16 Broca's, 15 Wernicke's, 10 global, and 9 amnesic), 13 nonaphasic brain damaged patients, and 13 normal adults to evaluate the effect of semantic plausibility on sentence comprehension in active affirmative declarative sentences with a sentence-picture matching task. A plate of two pictures was provided for each stimulus sentence, and the subject was required to choose the picture corresponding to the sentence presented auditorily. Two types of sentences in terms of plausibility were prepared, i.e., probable sentences (P) describing common events in our daily life and improbable sentences (I) describing rare events. There were four kinds of combinations of a picture with the other to make a correct/(distractor) set, i.e., P/(P), P/(I), I/(P), and I/(I) constructions. The results indicated that probable sentences were more comprehensible than improbable sentences, and that the effect of semantic plausibility did not differ among aphasic types.     

Preference for gamma-hydroxybutyrate (GHB) in current users

Gamma-hydroxybutyrate (GHB) is a drug with significant abuse potential. The present study aimed to assess the relative value of escalating doses of GHB to current GHB users via the Multiple Choice Procedure (MCP), and to validate that the dose rated highest with the MCP would be self-administered at a greater rate than placebo. Participants were 5 current GHB users who were not currently trying to stop using GHB. To examine the value of escalating doses of GHB, the following doses of GHB were used: 0 (placebo), 12.5, 25, 37.5, and 50 mg/kg. Participants typically assigned higher doses of GHB had higher crossover points on the MCP. During choice sessions, participants made repeated choices between administering GHB, placebo or nothing. All participants selected GHB exclusively (5 out of 5 instances) except for one participant who selected GHB on 4 out of 5 instances, thus 96% (i.e., 24/25) of choices were for active GHB. Based on these data, GHB appears likely to function as a dose-dependent reinforcer for humans based on our sample.     

Use of nonsexist pronouns as a function of one's feminist orientation

Subjects of both sexes were shown several sentences that contained a blank space where a third-person singular pronoun should be, and were asked to indicate what pronoun they would choose to complete the sentence. Some sentences referred to traditionally masculine positions (e.g., lawyer), some referred to traditionally feminine positions (e.g., secretary), and some referred to positions with generic titles (e.g., spokesman). As hypothesized, subjects with high scores on Spence and Helmreich's (1972) Attitudes toward Women Scale (AWS) chose nonsexist pronouns more frequently on all three types of sentences than did subjects with low AWS scores. Less feminist trends in the subjects' pronoun choices are discussed.     

The use of pupillometry in the study of on-line verbal processing: evidence for depths of processing

The effect of context and task demand upon the perception and resolution of lexical ambiguities was investigated in three experiments using pupillary measurements. Sentence type (ambiguous, disambiguous, and control) was tested under three conditions ("recall," "define word," and "choose best meaning"). All types of ambiguous sentences had higher pupillary curves than unambiguous sentences, with a particularly sharp rise in pupil size following the homophone. In addition, differences were observed in total sentence rise among the three task demands, such that the definition task was higher than recall, while the "choice" task exhibited a continuing rise after the sentence, which both other tasks did not have. Results are discussed in relation to putative processing stages of sentences, such as lexical search and sentence integration, and the more general issue of depths of processing.     

On-line and off-line reflexive resolution in Japanese logophoric sentences

This study investigates on-line and off-line resolution of a Japanese reflexive,jibun, for logophoric sentences, i.e., complex sentences involving a matrix verb that reflects one's point of view feelings, or state of consciousness, and for nonlogophoric sentences, i.e., complex sentences involving a subordinate adverbial clause. According to Kuroda's (1973) thesis and Chomsky's (1981) binding principle (for nonlogophoric sentences only), the reflexive in the logophoric sentences can be associated with the subject of both a matrix sentence and a subordinate sentence whereas that in the nonlogophoric sentences can only be associated with the subject of the subordinate sentence. In Experiment 1, 42 students were administered a probe-recognition task in which a probe was given for the subject either of the matrix sentence or of the subordinate sentence immediately after the end of the subordinate clause or at the end of a sentence following the matrix verb. Recognition times were faster for a matrix-subject probe than for a subordinatesubject probe regardless of the sentence type and probe position. In Experiment 2, 40 students were administered an on-line antecedent identification task in which they were required to quickly and accurately identify, when given a probe, the antecedent of the reflexive, with the probe given after the reflexive or at the end of a sentence. Regardless of the sentence type, matrix-subject was judged to be the antecedent of the reflexive more often than subordinate-subject, with the effect of probe position being negligible. An offline study required 136 students to indicate the antecedent(s) for the two types of sentence given in their entirety. No effect of sentence type was found. Findings indicate that neither Kuroda's thesis nor Chomsky's binding principle is applied when Japanese speakers parse logophoric and nonlogophoric sentences.Part of this study was supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science and Culture, No. 05610067. Deep gratitude is due to Professor D. D. Steinberg for reading an earlier version of this paper. Thanks are also due to Ms. S. Ogawa for her help in collecting part of the off-line data.