Grammatical SLI Research Articles

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.

A challenge to current models of past tense inflection: The impact of phonotactics

Is past tense production better modelled by a Single Mechanism or a Words and Rules model? We present data concerning a phenomenon that has not been considered by either model—regular past tense verbs with contrasting phonotactics. One set of verbs contains clusters at the inflected verb end that also occur in monomorphemic words (‘monomorphemically legal clusters’, MLC) whereas the other has clusters that can only occur in inflected forms (‘monomorphemically illegal clusters’, MIC). We argue that if children apply a morphological rule, phonotactics will not affect performance. Conversely, if children store past tense forms, they will perform better on verbs with MLCs because these clusters are more frequent. We investigated three populations—typically developing children, Grammatical-SLI (G-SLI) and Williams Syndrome (WS)—using past tense elicitation tasks. In Experiment 1 we reanalyse data from van der Lely and Ullman [van der Lely, H. K. J. & Ullman, M. (2001). Past tense morphology in specifically language impaired and normally developing children. Language and Cognitive Processes, 16: 177–217] and show that G-SLI children perform better on MLC verbs, whereas for typically developing children phonotactics do not affect performance. In Experiment 2 we replicate these findings in new groups of G-SLI and typically developing children. In Experiment 3 we reanalyse data from Thomas et al. [Thomas, M. S. C., Grant, J., Barham, Z., Gsodl, M., Laing, E., Lakusta, L., Tyler, L.K., Grice, S., Paterson, S. & Karmiloff-Smith, A. (2001) Past tense formation in Williams Syndrome. Language and Cognitive Processes, 16: 143–176] and show that phonotactics do not affect performance in individuals with WS. We argue that the results elucidate the underlying nature of morphology in these populations, and are better accommodated within a Words and Rules model of past tense acquisition.

Wh-Movement in Children with Grammatical SLI: A Test of the RDDR Hypothesis

This article presents a test of the proposal that a subgroup of children with GRAMMATICAL-SPECIFIC LANGUAGE IMPAIRMENT (G-SLI) have optional movement (the REPRESENTATIONAL DEFICIT FOR DEPENDENT RELATIONS (RDDR) account, van der Lely 1998) by investigating wh-movement in fifteen G-SLI subjects and twenty-four younger children matched on language abilities (LA controls). The RDDR/optional movement account predicts that G-SLI subjects would have deficits with both wH-operator and Q-feature movement and therefore would have particular problems producing object questions. We elicited 36 questions balanced for subject and object questions and WH-words (who, which, what). The G-SLI subjects were significantly impaired in producing WH-questions, showing particular difficulties with object questions in relation to the control children. The majority of G-SLI subjects (80%) evinced both wh-operator and T/Q-feature movement errors whereas only one control child (4%) did so, yet on occasion all the G-SLI subjects used appropriate movement operations to satisfy the wh-criterion. We conclude that the RDDR account whereby movement is optional is consistent with the findings of correct and incorrect wh-question formation. Thus, this first test of the RDDR account of G-SLI is supported by the findings. We discuss the possible underlying nature of a grammar that could cause such optionality, the implications for normal and impaired language acquisition, and the generalizability of the findings to other groups of children with SLI. We propose that in the face of no movement, the wh-word and, on occasion, do are merged in situ in the CP, and function as an interrogative adjunct.

Grammatical SLI: A distinct subtype of developmental language impairment?

Grammatical specific language impairment (G-SLI) has been proposed as a distinct subtype of language impairment. We assessed a large sample of twins between the ages of 7 and 13 years on language comprehension tests sensitive to G-SLI. The sample included 37 same-sex twin pairs selected for the presence of language impairment (LI) in one or both twins and 104 twin pairs from the general population. The number and patterns of errors in those with LI replicated findings from previous studies of G-SLI. Qualitative markers of G-SLI were derived from the tests. Out of 144 children for whom complete data were available, 2 scored positive on all five markers and 9 scored positive on four of the five markers. Most children who made grammatical errors characteristic of G-SLI had co-occurring deficits in other areas. These results raise questions for theories that treat this disorder as an all-or-none modular deficit.

Learning from Grammatical SLI: Response to J.B. Tomblin and J. Pandich (1999)

The author is supported by a Wellcome Trust Fellowship (044179/Z/95/Z). I thank Alastair McClelland for statistical advice and Gary Marcus for comments on an early draft.

Language and cognitive development in a grammatical sli boy: Modularity and innateness

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 AZ's severely impaired modular language abilities and good non-modular and non-linguistic abilities. AZ's 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 AZ's 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 AZ's 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.

Binding theory and grammatical specific language impairment in children

This study investigates the intrasentential assignment of reference to pronouns ( him, her) and anaphors ( himself, herself) as characterized by Binding Theory in a subgroup of “Grammatical specifically language-impaired” (SLI) children. The study aims to (1) provide further insight into the underlying nature of Grammatical SLI in children and (2) elucidate the relationship between different sources of knowledge, that is, syntactic knowledge versus knowledge of lexical properties and pragmatic inference in the assignment of intrasentential coreference. In two experiments, using a picture–sentence pair judgement task, the children's knowledge of the lexical properties versus syntactic knowledge (Binding Principles A and B) in the assignment of reflexives and pronouns was investigated. The responses of 12 Grammatical SLI children (aged 9:3 to 12:10) and three language ability (LA) control groups of 12 children (aged 5:9 to 9:1) were compared. The results indicated that the SLI children and the LA controls may use a combination of conceptual–lexical and pragmatic knowledge (e.g., semantic gender, reflexive marking of the predicate, and assignment of theta roles) to help assign reference to anaphors and pronouns. The LA controls also showed appropriate use of the syntactic knowledge. In contrast, the SLI children performed at chance when syntactic information was crucially required to rule out inappropriate coreference. The data are consistent with an impairment with the (innate) syntactic knowledge characterized by Binding Theory which underlies reference assignment to anaphors and pronouns. We conclude that the SLI children's syntactic representation is underspecified with respect to coindexation between constituents and the syntactic properties of pronouns. Support is provided for the proposal that Grammatical SLI children have a modular language deficit with syntactic dependent structural relationships between constituents, that is, a Representational Deficit with Dependent Relationships (RDDR). Further consideration of the linguistic characteristics of this deficit is made in relation to the hypothesized syntactic representations of young normally developing children. © 1997 Elsevier Science B.V.

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.