Sentence-level Language Research Articles

Syntax, concepts, and logic in the temporal dynamics of language comprehension: Evidence from event-related potentials

Logic has been intertwined with the study of language and meaning since antiquity, and such connections persist in present day research in linguistic theory (formal semantics) and cognitive psychology (e.g., studies of human reasoning). However, few studies in cognitive neuroscience have addressed logical dimensions of sentence-level language processing, and none have directly compared these aspects of processing with syntax and lexical/conceptual-semantics. We used ERPs to examine a violation paradigm involving “Negative Polarity Items” or NPIs (e.g., ever/any), which are sensitive to logical/truth-conditional properties of the environments in which they occur (e.g., presence/absence of negation in: John hasn’t ever been to Paris, versus: John has *ever been to Paris). Previous studies examining similar types of contrasts found a mix of effects on familiar ERP components (e.g., LAN, N400, P600). We argue that their experimental designs and/or analyses were incapable of separating which effects are connected to NPI-licensing violations proper. Our design enabled statistical analyses teasing apart genuine violation effects from independent effects tied solely to lexical/contextual factors. Here unlicensed NPIs elicited a late P600 followed in onset by a late left anterior negativity (or “L-LAN”), an ERP profile which has also appeared elsewhere in studies targeting logical semantics. Crucially, qualitatively distinct ERP-profiles emerged for syntactic and conceptual semantic violations which we also tested here. We discuss how these findings may be linked to previous findings in the ERP literature. Apart from methodological recommendations, we suggest that the study of logical semantics may aid advancing our understanding of the underlying neurocognitive etiology of ERP components.

Semantic processing and thought disorder in childhood-onset schizophrenia: Insights from fMRI

Impairments in language processing and thought disorder are core symptoms of schizophrenia. Here we used fMRI to investigate functional abnormalities in the neural networks subserving sentence-level language processing in childhood-onset schizophrenia (COS). Fourteen children with COS (mean age: 13.34; IQ: 95) and 14 healthy controls (HC; mean age: 12.37; IQ: 104) underwent fMRI while performing a semantic judgment task previously shown to differentially engage semantic and syntactic processes. We report four main results. First, different patterns of functional specialization for semantic and syntactic processing were observed within each group, despite similar level of task performance. Second, after regressing out IQ, significant between-group differences were observed in the neural correlates of semantic and, to a lesser extent, syntactic processing, with HC children showing overall greater activity than COS children. Third, while these group differences were not related to effects of medications, a significant negative correlation was observed in the COS group between neuroleptic dosage and activity in the left inferior frontal gyrus for the semantic condition. Finally, COS children's level of thought disorder was significantly correlated with task-related activity in language-relevant networks. Taken together, these findings suggest that children with COS exhibit aberrant patterns of neural activity during semantic, and to a lesser extent syntactic, processing and that these functional abnormalities in language-relevant networks are significantly related to severity of thought disorder.

Perceptual Systems Controlling Speech Production

It is proposed that the acquisition and maintenance of fluent speech depend on the rapid temporal integration of motor feedforward and polysensory (auditory and somatosensory) feedback signals. In a functional magnetic resonance imaging study on 21 healthy right-handed, English-speaking volunteers, we investigated activity within these motor and sensory pathways and their integration during speech. Four motor conditions were studied: two speech conditions (propositional and nonpropositional speech) and two silent conditions requiring repetitive movement of the principal articulators (jaw and tongue movements). The scanning technique was adapted to minimize artifact associated with overt speech production. Our result indicates that this multimodal convergence occurs within the left and right supratemporal planes (STPs), with peaks of activity at their posteromedial extents, in regions classically considered as unimodal auditory association cortex. This cortical specialization contrasted sharply with the response of somatosensory association cortex (SII), in which activity was suppressed during speech but not during the silent repetitive movement of the principal articulators. It was also clearly distinct from the response of lateral auditory association cortex, which responded to auditory feedback alone, and from that within a left lateralized ventrolateral temporal and inferior frontal system, which served lexical- and sentence-level language retrieval. This response of cortical regions related to speech production is not predicted by the classical model of hierarchical cortical processing, providing new insights into the role of the STP in polysensory integration and into the modulation of activity in SII during normal speech production. These findings have novel implications for the acquisition and maintenance of fluent speech.

Amnesic H.M. exhibits parallel deficits and sparing in language and memory: Systems versus binding theory accounts

This study examines sentence-level language abilities of amnesic H.M. to test competing theoretical conceptions of relations between language and memory. We present 11 new sources of experimental evidence indicating deficits in H.M's comprehension and production of non-cliché sentences. Contrary to recent claims that H.M.'s comprehension is unimpaired at grammatical levels, H.M. performed 2–6 standard deviations worse than controls matched for age, IQ and education in seven tasks: detecting grammatical errors, repairing sentences identified as containing an error, answering questions about who did what to whom in sentences, multiple-choice recognition of possible versus impossible interpretations of sentences containing ambiguities and figurative speech, discrimination between grammatical versus ungrammatical sentences, and describing the meanings of ambiguous sentences, phrases, and words. However, H.M.'s deficits were selective, e.g., sparing comprehension of familiar but not unfamiliar phrases. Parallels between H.M.'s selective deficits in language, memory and other aspects of cognition, e.g., reading and visual cognition are discussed. These parallels were predicted under binding theory but did not have a parsimonious explanation in systems theories that postulate non-overlapping units and processes for language versus memory.

Phonological typicality influences on-line sentence comprehension

Since Saussure, the relationship between the sound and the meaning of words has been regarded as largely arbitrary. Here, however, we show that a probabilistic relationship exists between the sound of a word and its lexical category. Corpus analyses of nouns and verbs indicate that the phonological properties of the individual words in these two lexical categories form relatively separate and coherent clusters, with some nouns sounding more typical of the noun category than others and likewise for verbs. Additional analyses reveal that the phonological properties of nouns and verbs affect lexical access, and we also demonstrate the influence of such properties during the on-line processing of both simple unambiguous and syntactically ambiguous sentences. Thus, although the sound of a word may not provide cues to its specific meaning, phonological typicality, the degree to which the sound properties of an individual word are typical of other words in its lexical category, affects both word- and sentence-level language processing. The findings are consistent with a perspective on language comprehension in which sensitivity to multiple syntactic constraints in adulthood emerges as a product of language-development processes that are driven by the integration of multiple cues to linguistic structure, including phonological typicality.

Discourse Macrolevel Processing After Severe Pediatric Traumatic Brain Injury

The purpose of this study was to determine if discourse macrolevel processing abilities differed between children with severe traumatic brain injury (TBI) at least 2 years postinjury and typically developing children. Twenty-three children had sustained a severe TBI either before the age of 8 (n = 10) or after the age of 8 (n = 13). The remaining 32 children composed a control group of typically developing peers. The groups' summaries and interpretive lesson statements were analyzed according to reduction and transformation of narrative text information. Compared to the control group, the TBI group condensed the original text information to a similar extent. However, the TBI group produced significantly less transformed information during their summaries, especially those children who sustained early injuries. The TBI and control groups did not significantly differ in their production of interpretive lesson statements. In terms of related skills, discourse macrolevel summarization ability was significantly related to problem solving but not to lexical or sentence level language skills or memory. Children who sustain a severe TBI early in childhood are at an increased risk for persisting deficits in higher level discourse abilities, results that have implications for academic success and therapeutic practices.

Analysis of narrative ability in children with cochlear implants.

The purposes of this study were to: 1) develop a scoring system to assess narrative ability in children; 2) evaluate the impact of auditory speech perception with a cochlear implant on narrative ability; and 3) evaluate the importance of narrative ability to reading comprehension in deaf children. Narrative productions prompted from an eight-picture sequence story were elicited from 8 and 9 yr olds; 87 who had at least 4 yr of cochlear implant experience and 28 who had normal hearing. The stories were transcribed and a scoring system for narrative ability was developed based on the use of complete narrative structure, conjunctions linking semantic relations, and referents that served to identify and distinguish characters in the narrative. Narrative ability scores of cochlear implant users were examined in relation to their age, IQ, speech perception, language, and reading test scores. In addition, narrative ability scores for children with normal hearing were compared with two groups of cochlear implant users, those with above average speech perception scores and those with below average speech perception scores. Within the sample of hearing-impaired children, narrative ability scores correlated significantly with speech perception, language syntax, and reading test scores. A multiple regression analysis was conducted to predict reading comprehension scores from four predictor variables (age, IQ, language syntax, and narrative ability). Results reflected the independent contribution of discourse-level language skills, as measured by the narrative ability score, as well as sentence-level language skills in predicting reading test scores. Analysis of stories obtained from 8- and 9-yr-old children with normal hearing revealed the classic pattern that included a high point, a resolution, and one or more evaluative statements. Their stories achieved cohesion from correct use of both conjunctions and referents. Deaf children who received above-average speech perception scores with a cochlear implant (i.e., scored above 48% on the Word Intelligibility by Picture Identification speech perception test) told narratives that were similar in structure and use of referents to those of age mates with normal hearing. Although their use of subordinate conjunctions was not as well developed as normal-hearing children, it was significantly above that of deaf children who received less speech perception benefit after a similar period of implant use. These below-average speech perceivers exhibited significantly poorer use of narrative structure and cohesive devices than either normal-hearing age mates or children who achieved above average speech perception with a cochlear implant. Narrative ability is an important predictor of reading comprehension ability in deaf children above and beyond IQ and syntactic competence. Children who receive a cochlear implant under 5 yr of age and obtain above average speech perception benefit from the device construct narratives that are similar in structure and cohesion to those of their hearing age mates by age 8 to 9.