The comprehension of anomalous sentences: evidence from structural priming

We report three experiments investigating how people process anomalous sentences, in particular those in which the anomaly is associated with the verb. We contrast two accounts for the processing of such anomalous sentences: a syntactic account, in which the representations constructed for anomalous sentences are similar in nature to the ones constructed for well-formed sentences; and a semantic account, in which the representations constructed for anomalous sentences are erroneous, or altogether missing, and interpretation is achieved on the basis of semantic representations instead. To distinguish between these accounts, we used structural priming. First, we ruled out the possibility that anomaly per se influences the magnitude of the priming effect: Prime sentences with morphologically incorrect verbs produced similarly enhanced priming (lexical boost) to sentences with the same correct verbs (Exp. 1). Second, we found that prime sentences with a novel verb (Exp. 2) or a semantically and syntactically incongruent verb (Exp. 3) produced a priming effect, which was the same as that produced by well-formed sentences. In accord with the syntactic account, we conclude that the syntactic representations of anomalous sentences are similar to those constructed for well-formed sentences. Our results furthermore suggest that lexically-independent syntactic information is robust enough to produce well-formed syntactic representations during processing without requiring aid from lexically-based syntactic information.     

Past tense formation and comprehension of passive sentences in Parkinson's disease: evidence from Greek

The present study investigates the production of regular and irregular verbs in the past tense and the comprehension of passive sentences by Greek-speaking PD patients, and compares their behavior to that of normal speakers. Although the two groups manifest large scale differences at all the above constructions, the behavior of PDs is not different at regular vs. irregular past tense formation neither did we obtain strong evidence that they do not comprehend passives, most importantly, they certainly do not perform at chance. On the basis of the above, we conclude that there are no indications for a clearly linguistic deficit of the PD group, hence, their difference with the control group should be attributed to other factors, such as the computational demands of the tasks.     

The specificity of perceptual learning in speech processing

We conducted four experiments to investigate the specificity of perceptual adjustments made to unusual speech sounds. Dutch listeners heard a female talker produce an ambiguous fricative [?] (between [f] and [s]) in [f]- or [s]-biased lexical contexts. Listeners with [f]-biased exposure (e.g., [witlo?]; from witlof, "chicory"; witlos is meaningless) subsequently categorized more sounds on an [epsilonf]-[epsilons] continuum as [f] than did listeners with [s]-biased exposure. This occurred when the continuum was based on the exposure talker's speech (Experiment 1), and when the same test fricatives appeared after vowels spoken by novel female and male talkers (Experiments 1 and 2). When the continuum was made entirely from a novel talker's speech, there was no exposure effect (Experiment 3) unless fricatives from that talker had been spliced into the exposure talker's speech during exposure (Experiment 4). We conclude that perceptual learning about idiosyncratic speech is applied at a segmental level and is, under these exposure conditions, talker specific.     

Bilateral capacity for speech sound processing in auditory comprehension: evidence from Wada procedures

Data from lesion studies suggest that the ability to perceive speech sounds, as measured by auditory comprehension tasks, is supported by temporal lobe systems in both the left and right hemisphere. For example, patients with left temporal lobe damage and auditory comprehension deficits (i.e., Wernicke's aphasics), nonetheless comprehend isolated words better than one would expect if their speech perception system had been largely destroyed (70-80% accuracy). Further, when comprehension fails in such patients their errors are more often semantically-based, than-phonemically based. The question addressed by the present study is whether this ability of the right hemisphere to process speech sounds is a result of plastic reorganization following chronic left hemisphere damage, or whether the ability exists in undamaged language systems. We sought to test these possibilities by studying auditory comprehension in acute left versus right hemisphere deactivation during Wada procedures. A series of 20 patients undergoing clinically indicated Wada procedures were asked to listen to an auditorily presented stimulus word, and then point to its matching picture on a card that contained the target picture, a semantic foil, a phonemic foil, and an unrelated foil. This task was performed under three conditions, baseline, during left carotid injection of sodium amytal, and during right carotid injection of sodium amytal. Overall, left hemisphere injection led to a significantly higher error rate than right hemisphere injection. However, consistent with lesion work, the majority (75%) of these errors were semantic in nature. These findings suggest that auditory comprehension deficits are predominantly semantic in nature, even following acute left hemisphere disruption. This, in turn, supports the hypothesis that the right hemisphere is capable of speech sound processing in the intact brain.     

New evidence for the perceptual precedence of global information

Two experiments are reported investigating the order in which global and local information of visual forms is processed. Subjects were presented with compound stimuli and were asked to identify the local level, always consisting of small letters. At the global level, the stimuli could be either large letters, consistent or inconsistent with the local level, or meaningless patterns derived from the large letters by modifying the spatial relations among segments. Results showed that inconsistent stimuli were responded to more slowly than both consistent stimuli and meaningless patterns, which did not differ from each other. This was true both when letters and patterns were presented intermixed, as in experiment 1 or separately, as in experiment 2. The pattern obtained accords well with predictions derived from the perceptual precedence hypothesis which states that global information becomes available at a faster rate than local information. No support for the alternative, post-perceptual, hypothesis was found.     

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.     

Recovery from aphasia: Spontaneous speech versus language comprehension

Seventy-four aphasic patients, subdivided into four groups (fluent, mixed, nonfluent, and severely nonfluent), were tested three times in the course of 1 year to assess recovery of spontaneous speech and sentence comprehension. Although 12 of the 28 spontaneous speech variables employed showed significant time changes, some of these changes indicated improvement and others deterioration. There was no overall clinical improvement in spontaneous speech in any group. On the sentence comprehension tests, however, all four groups did show considerable, significant improvement. There were no qualitative or quantitative differences among the groups in the course of recovery, despite the fact that the groups differed in the severity of aphasia as well as on the fluency dimension. In certain patients there was also some improvement in spontaneous speech, but this did not in most cases correlate with an improvement in either fluency or sentence comprehension. Possible reasons why receptive abilities improved more than expressive abilities are discussed.     

Lexical decision in sentences: Effects of syntactic structure

A lexical decision paradigm was used to examine syntactic influence on word recognition in sentences. Initial fragments of sentences were presented visually (CRT display) one word at a time (at reading speeds), from left to right. The string terminated with the appearance of a lexical decision target. The grammatical structure of the incomplete sentence affected lexical decision reaction time (RT). In Experiment 1, modal verb contexts followed by main verb targets and preposition contexts followed by noun targets produced lower RTs than did the opposite pairings (i.e., modal/noun and preposition/verb). In Experiment 2, transitive verb contexts followed by noun targets and subject noun phrase contexts followed by verb targets yielded lower RTs than did the opposite pairings. Similar contrasts for adjective targets did not yield comparable effects in Experiment 2, but did when the adjective was the head of a predictable phrase (Experiment 4). In Experiment 3, noun targets yielded lower RTs than did verb targets after contexts of a transitive verb followed by a prepositional phrase. An account of these effects is offered in terms of parsing constraints on phrasal categories.     

Physical similarity (and not quantity representation) drives perceptual comparison of numbers: evidence from two Indian notations

Numerical quantity seems to affect the response in any task that involves numbers, even in tasks that do not demand access to quantity (e.g., perceptual tasks). That is, readers seem to activate quantity representations upon the mere presentation of integers. One important piece of evidence in favor of this view comes from the finding of a distance effect in perceptual tasks: When one compares two numbers, response times (RTs) are a function of the numerical distance between them. However, recent studies have suggested that the physical similarity between Arabic numbers is strongly correlated with their numerical distance, and that the former could be a better predictor of RT data in perceptual tasks in which magnitude processing is not required (Cohen, 2009a). The present study explored the Persian and Arabic versions of Indian numbers (Exps. 1 and 2, respectively). Na?ve participants (speakers of Spanish) and users of these notations (Pakistanis and Jordanians) participated in a physical same–different matching task. The RTs of users of the Indian notations were regressed on perceptual similarity (estimated from the Spanish participants’ RTs) and numerical distance. The results showed that, regardless of the degree of correlation between the perceptual similarity function and the numerical distance function, the critical predictor for RTs was perceptual similarity. Thus, participants do not automatically activate Indian integers’ quantity representations, at least not when these numbers are presented in simple perceptual tasks.     

Against the perceptual model of utterance comprehension

Philosophical Studies - What accounts for the capacity of ordinary speakers to comprehend utterances of their language? The phenomenology of hearing speech in one’s own language makes it...     

Early use of phonetic information in spoken word recognition: Lexical stress drives eye movements immediately

For optimal word recognition listeners should use all relevant acoustic information as soon as it comes available. Using printed-word eye tracking we investigated when during word processing Dutch listeners use suprasegmental lexical stress information to recognize words. Fixations on targets such as “OCtopus” (capitals indicate stress) were more frequent than fixations on segmentally overlapping but differently stressed competitors (“okTOber”) before segmental information could disambiguate the words. Furthermore, prior to segmental disambiguation, initially stressed words were stronger lexical competitors than noninitially stressed words. Listeners recognize words by immediately using all relevant information in the speech signal.     

Effects of task on the perceptual organization of sentences

Children and college students listened to sentences and responded to a question or a probe word after each sentence. To prevent Ss from using different perceptual strategies in performing the two tasks, question items and probe items were presented in mixed lists. In the probe task, the relationship between sentence structure and correct response latencies resembled the findings of an earlier study with block lists. The results from the question task were less similar to those obtained earlier, perhaps because, with mixed lists, Ss tended to organize all sentences in a manner especially suited to the probe task. A different type of organization might be used in the process of comprehending a sentence solely for the purpose of answering questions.     

Immediate and delayed recall of visually presented sentences: evidence for the involvement of phonological information

The lure intrusion effect refers to the observation that lexical priming affects recall of sentences. This effect is taken as evidence against the contribution of surface information, even with immediate sentence recall. Recently, Rummer and Engelkamp (2003a) demonstrated that this effect, which is usually observed under rapid serial visual presentation (RSVP), does not appear under immediate recall of auditorily presented sentences. This finding indicates that surface information (i.e., phonological or acoustic-sensory information) can contribute to immediate sentence recall. So far, however, the findings do not allow for a decision on whether phonological and/or acoustic-sensory information is used in immediate sentence recall. In order to dissociate the two kinds of surface information, an experiment was conducted in which immediate and delayed recall were tested for sentences that were visually presented for a longer period of time than in RSVP. This kind of presentation should support phonological representations, but does not allow for acoustic-sensory representations. The findings showed a smaller intrusion effect for immediate than for delayed recall. This indicates that, if available, phonological information is involved in immediate sentence recall thereby reducing the lure intrusion effect. Furthermore, the findings support the assumption that the phonological trace provided via RSVP reading is weaker than in normal reading.     

Memory predictions are influenced by perceptual information: evidence for metacognitive illusions

Although perceptual information is utilized to judge size or depth, little work has investigated whether such information is used to make memory predictions. The present study examined how the font size of to-be-remembered words influences predicted memory performance. Participants studied words for a free-recall test that varied in font size and made judgments of learning (JOLs) for each item. JOLs were influenced by font size, as larger font sizes were given higher JOLs, whereas little relationship was evident between font size and recall. The effect was modified when other, more valid, sources of information (e.g., associative strength) were available when JOLs were made and persisted despite experience with multiple study-test sessions, use of a forgetting scale to assess predictions, and explicit warning of participants that font size has little effect on memory performance. When ease of reading was manipulated, such that large font size words were made less fluent, the effect was eliminated. Thus, highly accessible perceptual cues can strongly influence JOLs, likely via encoding fluency, and this effect can lead to metacognitive illusions     

No difference between conscious and nonconscious visuomotor control: evidence from perceptual learning in the masked prime task

Negative compatibility effects (NCEs) in the masked-prime paradigm are usually obtained when primes are masked effectively. With ineffective masks-and primes above the perceptual threshold-positive compatibility effects (PCEs) occur. We investigated whether this pattern reflects a causal relationship between conscious awareness and low-level motor control, or whether it reflects the fact that both are affected in the same way by changes in physical stimulus attributes. In a 5-session perceptual learning task, participants learned to consciously identify masked primes. However, they showed unaltered NCEs that were not different from those produced by participants in a control group without equivalent perceptual learning. A control experiment demonstrated that no NCEs occur when prime identification is made possible by ineffective masking. The results suggest that perceptual awareness and low-level motor control are affected by the same factors, but are fundamentally independent of each other.     

Processing of perceptual information is more robust than processing of conceptual information in preschool-age children: evidence from costs of switching

Is processing of conceptual information as robust as processing of perceptual information early in development? Existing empirical evidence is insufficient to answer this question. To examine this issue, 3- to 5-year-old children were presented with a flexible categorization task, in which target items (e.g., an open red umbrella) shared category membership with one test item (e.g., a folded umbrella) and perceptual characteristics with another test item (e.g., a red mushroom). Participants were instructed to either categorize stimuli by the same dimension (i.e., perceptual similarity or category membership) in both phases of the task, or switch from categorizing by one dimension to categorizing by the other dimension. Results pointed to a strong asymmetry in switch costs: conceptual switch costs were higher than perceptual switch costs. These results suggest that processing of perceptual information remains more robust than processing of conceptual information at least until 5 years of age.     

On the universality of language comprehension strategies: evidence from Turkish

A fundamental question in psycholinguistic research concerns the universality of comprehension strategies. We investigated this issue by examining the so-called "subject preference" in Turkish, a language which allows for a natural (unmarked) object reading of an initial ambiguous argument. Using event-related brain potentials (ERPs), we observed increased processing difficulty in the form of a broadly distributed positivity when an initial ambiguous argument was disambiguated towards an object reading. This effect was independent of the animacy (i.e. semantic subject prototypicality) of the ambiguous argument. Our results therefore speak in favour of a universal tendency to interpret the first argument encountered as the "subject" of the clause, even in languages providing no obvious structural motivation for such a strategy. However, we argue that the underlying explanation for this preference must be modified in accordance with cross-linguistic considerations.     

Processing resource capacity and the comprehension of garden path sentences

Three experiments explored the relationship between verbal working memory capacity and the comprehension of garden path sentences. In Experiment 1, subjects with high, medium, and low working memory spans made acceptability judgments about garden path and control sentences under whole sentence and rapid serial visual presentation (RSVP) conditions. There were no significant differences between subjects with different working memory spans in the comprehension of garden path sentences in either condition. In Experiments 2A and 2B, subjects with high and low working memory spans were tested on the same materials at three RSVP rates. There were no significant differences between subjects with different working memory spans in the magnitude of the effect of garden path sentences at any presentation rate. The results suggest that working memory capacity, as measured by the Daneman and Carpenter (1980) reading span task, is not a major determinant of individual differences in the processing of garden path sentences.     

Syntactic priming in comprehension: evidence from event-related potentials

Syntactic priming is the facilitation of processing that occurs when a sentence has the same syntactic form as a preceding sentence. Such priming effects have been less consistently demonstrated in comprehension than in production, and those that have been reported have depended on the repetition of verbs across sentences. In an event-related potential experiment, subjects read target sentences containing reduced-relative clauses. Each was preceded by a sentence that contained the same verb and either a reduced-relative or a main-clause construction. Reduced-relative primes elicited a larger positivity than did main-clause primes. Reduced-relative targets that were preceded by a main-clause prime elicited a greater positivity than the same target sentences following a reduced-relative prime. In addition, syntactic priming effects were dissociated from effects of lexical repetition at the verb.