Heather K. J. van der Lely

Specifically language impaired and normally developing children : Verbal passive vs. adjectival passive sentence interpretation

Abstract The focus of this study is the acquisition and underlying syntactic representation of passive sentences in a subgroup of 15 ‘Grammatical specifically language impaired’ (SLI) children (aged 9:3–12:10) and 36 younger normally developing, language ability (LA) control children (aged 5:5–8:9). In particular, the paper is concerned with the differences between a verbal and adjectival passive interpretation of the passive participle in short passive sentences. Van der Lely (1994) proposed that SLI children have a ‘Representational Deficit for Dependent Relationships’ (RDDR). The syntactic characterization of this deficit is not altogether clear, but I propose that problems with Spec-Head relations may provide an adequate description. This proposal predicts that SLI children should be able to derive an adjectival passive but not a verbal passive representation. Active, full and short progressive passive, and ambiguous (potentially adjectival) short passive sentences were investigated. A picture pointing response paradigm, in which the child chose one of four pictures, enabled responses to be differentiated: i.e. transitive (actional), adjectival (stative), and reversal (where thematic roles normally assigned to the subject or object were reversed). The test sentences were also administered to 12 adult subjects. The study revealed that Grammatical SLI children were significantly worse at interpreting transitive verbal passive sentences than the younger LA controls. The SLI children, and occasionally the younger LA controls, may interpret an unambiguously verbal passive sentence as an adjectival-stative passive. The SLI children showed a strong preference for an adjectival interpretation for the ambiguous passive sentences. Differences in the syntactic representations of verbal and adjectival passive sentences can account for the findings. The data indicate that the Grammatical SLI children and young children have problems deriving the syntactic representation underlying a verbal passive sentence but not the less complex adjectival-stative passive. The findings from this study for Grammatical SLI children are consistent with the proposed RDDR characterized by problems in Spec-Head relations. The study provides new empirical evidence for the different syntactic nature of verbal and adjectival passive sentences and has implications for language acquisition and the modularity of language.

Canonical linking rules: forward versus reverse linking in normally developing and specifically language-impaired children

Abstract Canonical linking rules for mapping thematic roles with syntactic functions were studied. Three experiments were undertaken to investigate the nature of productive forward linking (from semantics to syntax) and productive reverse linking (from syntax to semantics). I proposed that reverse linking, in contrast to forward linking, requires more detailed specification of the syntactic structure; that is, a syntactic representation which specifies each particular syntactic frame and all the argument positions within that frame. Six specifically language-impaired children (aged 6;1 to 9;6) were matched on language abilities to 17 younger, normally developing children (language age 3;1 to 6;6). In Experiment 1 — forward linking — the children were shown the meaning of a novel verb and had to describe the event using the novel verb. Experiment 2 — a comprehension task — required acting out sentences containing the newly learned verbs. In Experiment 3 — reverse linking — the children were told a sentence with a novel verb and had to act out its meaning, assigning thematic roles on the basis of the syntactic frame. Group and individual analysis generally revealed no significant differences between the specifically language-impaired children and the language age control children in Experiments 1 and 2, but a significant difference was found for Experiment 3. The normally developing children showed a good use of productive forward and reverse linking. The specifically language-impaired children demonstrated good productive forward linking but were significantly worse at reverse linking. An interpretation of the data, showing differences in the syntactic representation required for forward versus reverse linking, can account for the findings. I propose that a deficit in the area of “government” or “locality” which underlies c-selection and specifies the syntactic relationship between constituents can account for the data from this study and the data from previous investigations of specifically language-impaired children.

Phonological deficits in specific language impairment and developmental dyslexia: towards a multidimensional model

An on-going debate surrounds the relationship between specific language impairment and developmental dyslexia, in particular with respect to their phonological abilities. Are these distinct disorders? To what extent do they overlap? Which cognitive and linguistic profiles correspond to specific language impairment, dyslexia and comorbid cases? At least three different models have been proposed: the severity model, the additional deficit model and the component model. We address this issue by comparing children with specific language impairment only, those with dyslexia-only, those with specific language impairment and dyslexia and those with no impairment, using a broad test battery of language skills. We find that specific language impairment and dyslexia do not always co-occur, and that some children with specific language impairment do not have a phonological deficit. Using factor analysis, we find that language abilities across the four groups of children have at least three independent sources of variance: one for non-phonological language skills and two for distinct sets of phonological abilities (which we term phonological skills versus phonological representations). Furthermore, children with specific language impairment and dyslexia show partly distinct profiles of phonological deficit along these two dimensions. We conclude that a multiple-component model of language abilities best explains the relationship between specific language impairment and dyslexia and the different profiles of impairment that are observed.

Evidence for a grammar-specific deficit in children.

BACKGROUND Specific language impairment (SLI) is a disorder in which language acquisition is impaired in an otherwise normally developing child. SLI affects around 7% of children. The existence of a purely grammatical form of SLI has become extremely controversial because it points to the existence and innateness of a putative grammatical subsystem in the brain. Some researchers dispute the existence of a purely grammatical form of SLI. They hypothesise that SLI in children is caused by deficits in auditory and/or general cognitive processing, or social factors. There are also claims that the cognitive abilities of people with SLI have not yet been sufficiently characterised to substantiate the existence of SLI in a pure grammatical form. RESULTS We present a case study of a boy, known as AZ, with SLI. To investigate the claim for a primary grammatical impairment, we distinguish between grammatical abilities, non-grammatical language abilities and non-verbal cognitive abilities. We investigated AZs abilities in each of these areas. AZ performed normally on auditory and cognitive tasks, yet exhibited severe grammatical impairments. This is evidence for a developmental grammatical deficit that cannot be explained as a by-product of retardation or auditory difficulties. CONCLUSIONS The case of AZ provides evidence supporting the existence of a genetically determined, specialised mechanism that is necessary for the normal development of human language.

Language and cognitive development in a grammatical SLI boy: modularity and innateness

Abstract This paper aims to provide insight into the contentious issue of the hypothesised innate basis to domain specific, modular aspects of language [Fodor, F.J., The Modularity of Mind. MIT Press, Cambridge, MA, 1983; Chomsky, N., Lectures on government and binding. Foris, Dordrecht, 1981]. In order to do this a distinction is made between modular language abilities, non-modular language abilities (i.e. language abilities outside the language module in question) and non-linguistic cognitive tasks. Based on this distinction, a series of investigations were carried out into the abilities of a 10 year old boy (AZ) with Grammatical specific language impairment. The investigations of modular language abilities focused on inflectional morphology (agreement, and regular and irregular past tense marking) and syntax (knowledge and use of phrase structure, thematic role assignment and Binding Principles). The investigations of non-modular language abilities included tests of pragmatic inference and verbal analogical reasoning. Non-linguistic assessments included standardised tests and a test of visual transitive inference. A clear dissociation was revealed between AZs severely impaired modular language abilities and good non-modular and non-linguistic abilities. AZs performance on the tests was compared with 36 younger language control children (aged 5:4–8:9) and 12 age matched control children. Z-scores computed for AZs performance in comparison with the normal children, based on standardised language measures (vocabulary, morphology) and his chronological age, revealed a significant impairment in morpho-syntactic abilities and normal or above average abilities on the non-modular language tasks and non-linguistic cognitive tasks. I propose that the discreteness of AZs language impairment indicates that an underlying modular language impairment is the most parsimonious explanation for his deficit. A deficit with syntactic structural representations characterised by the Representational Deficit for Dependent Relationships [van der Lely, H.K.J. and Stollwerck, L., Binding theory and specifically language impaired children. Cognition, 1997.]can account for his morphological and syntactic impairments. The data provide empirical evidence to support the innate bases to domain specific and modular aspects of language.

The impact of phonological complexity on past tense inflection in children with Grammatical-SLI

English-speaking children with Specific Language Impairment (SLI) variably produce inflected and bare stem forms in obligatory past tense contexts. Researchers have not reached consensus as to whether the underlying deficit is morphosyntactic or morphophonological in nature. The Computational Grammatical Complexity (CGC) Hypothesis takes a different tack: it hypothesizes that for children with a particular form of SLI, Grammatical-SLI, the deficit is in representing linguistic structural complexity in at least three components of the computational grammatical system – syntax, morphology and phonology. Deficits in all these components are predicted to impact on regular past tense formation. The impact of syntactic and morphological complexity on G-SLI childrens realization of tense has been tested previously. Here we complete the picture by considering phonological effects on their production of regular past tense inflection. Using a past tense elicitation task where we manipulate the phonological complexity of the inflected verb end, we show that, as predicted, verb-end phonological complexity impacts on suffixation: G-SLI children are less likely to suffix stems when the inflected form ends in a consonant cluster. Typically developing controls show no such effect. The results of this study highlight the need to consider the independent contributions of language components to impaired and normal performance.

Narrative discourse in Grammatical specific language impaired children: a modular language deficit?*

This paper provides a further investigation into the linguistic abilities of a subgroup of 12 Grammatical specific language impaired (SLI) children (aged 10;2 to 13;11). The study investigates the use of referential expressions (e.g. pronouns) in a narrative discourse, and provides insight into the underlying nature of Grammatical SLI, thereby contributing to the modularity debate. Previous investigations indicate that Grammatical SLI children have a deficit with dependent structural relationships, i.e. a Representational Deficit for Dependent Relationships (RDDR). Grammatical SLI children’s RDDR appears to be a modular language deficit. To test this claim, linguistic representations of dependent structural relationships which are not part of the modular language system are investigated using a narrative discourse based on the picture book Frog where are you? The SLI children’s pattern of referential expressions was compared with 36 language ability controls (aged 6;4 to 9;8). The findings indicated that the Grammatical SLI children have relatively mature linguistic development in the use of referential expressions to produce a cohesive, structured narrative discourse. The view of the organisation of the mind in which a modular language system can be dierentially impaired from aspects of language which rely on the central system can most easily account for the data. Thus, the data support the hypothesized modular nature of Grammatical

Non-word repetition: An investigation of phonological complexity in children with Grammatical SLI

We investigate whether children with Grammatical Specific Language Impairment (G‐SLI) are also phonologically impaired and, if so, what the nature of that impairment is. We focus on the prosodic complexity of words, based on their syllabic and metrical (stress) structure, and investigate this using a novel non‐word repetition procedure, the Test of Phonological Structure (TOPhS). Participants with G‐SLI (aged 12–20 years) were compared to language‐matched, typically developing children (aged 4–8 years). The results reveal that, in contrast to the controls, the accuracy with which the G‐SLI group repeated non‐words decreased as prosodic complexity increased, even in non‐words with only one‐ and two‐syllables. The study indicates that, in G‐SLI, complexity deficits in morphology and syntax can extend to prosodic phonology. The study highlights the importance of taking into account prosodic complexity in phonological assessment and the design of non‐word repetition procedures.

Grammatical language impairment and the specificity of cognitive domains: relations between auditory and language abilities

Grammatical-specific language impairment (G-SLI) in children, arguably, provides evidence for the existence of a specialised grammatical sub-system in the brain, necessary for normal language development. Some researchers challenge this, claiming that domain-general, low-level auditory deficits, particular to rapid processing, cause phonological deficits and thereby SLI. We investigate this possibility by testing the auditory discrimination abilities of G-SLI children for speech and non-speech sounds, at varying presentation rates, and controlling for the effects of age and language on performance. For non-speech formant transitions, 69% of the G-SLI children showed normal auditory processing, whereas for the same acoustic information in speech, only 31% did so. For rapidly presented tones, 46% of the G-SLI children performed normally. Auditory performance with speech and non-speech sounds differentiated the G-SLI children from their age-matched controls, whereas speed of processing did not. The G-SLI children evinced no relationship between their auditory and phonological/grammatical abilities. We found no consistent evidence that a deficit in processing rapid acoustic information causes or maintains G-SLI. The findings, from at least those G-SLI children who do not exhibit any auditory deficits, provide further evidence supporting the existence of a primary domain-specific deficit underlying G-SLI.

Electrical Brain Responses in Language-Impaired Children Reveal Grammar-Specific Deficits

Background Scientific and public fascination with human language have included intensive scrutiny of language disorders as a new window onto the biological foundations of language and its evolutionary origins. Specific language impairment (SLI), which affects over 7% of children, is one such disorder. SLI has received robust scientific attention, in part because of its recent linkage to a specific gene and loci on chromosomes and in part because of the prevailing question regarding the scope of its language impairment: Does the disorder impact the general ability to segment and process language or a specific ability to compute grammar? Here we provide novel electrophysiological data showing a domain-specific deficit within the grammar of language that has been hitherto undetectable through behavioural data alone. Methods and Findings We presented participants with Grammatical(G)-SLI, age-matched controls, and younger child and adult controls, with questions containing syntactic violations and sentences containing semantic violations. Electrophysiological brain responses revealed a selective impairment to only neural circuitry that is specific to grammatical processing in G-SLI. Furthermore, the participants with G-SLI appeared to be partially compensating for their syntactic deficit by using neural circuitry associated with semantic processing and all non-grammar-specific and low-level auditory neural responses were normal. Conclusions The findings indicate that grammatical neural circuitry underlying language is a developmentally unique system in the functional architecture of the brain, and this complex higher cognitive system can be selectively impaired. The findings advance fundamental understanding about how cognitive systems develop and all human language is represented and processed in the brain.