The current study examined delays in syntax and morphology, and vocabulary, in autism spectrum disorder (ASD). Children ages 4-6 years with ASD (n = 21) and typical development (n = 21), matched on nonverbal mental age, completed five language tasks. The ASD group had significant delays in both syntax and morphology, and vocabulary measures, with…

Background: Fragile X syndrome (FXS) and Down syndrome (DS) are the two leading genetic causes of intellectual disability, and FXS is the most common known genetic condition associated with autism. Both FXS and DS are associated with significant language impairment, but little is known about expressive language across domains over time or the role…

The present study examined narrative development in children and adolescents with Down syndrome longitudinally. Narratives were collected from 32 children and adolescents with Down syndrome three times over a 1-year period. Both micro- and macrolevel analyses were conducted. Significant growth over the 1-year period was seen in semantic complexity…

We examined recalled narratives of boys with fragile X syndrome with autism spectrum disorder (FXS-ASD; N = 28) and without ASD (FXS-O; N = 29), and compared them to those of boys with Down syndrome (N = 33) and typically developing (TD) boys (N = 39). Narratives were scored for mentions of macrostructural story grammar elements (introduction,…

Background: For pre-school children, the home literacy environment (HLE) plays an important role in the development of language and literacy skills. As there is little known about the HLE of children with intellectual disabilities (ID), the aim of the present study was to investigate the HLE of children with ID in comparison with children without…

This study investigates the syntactic abilities of ten individuals with Williams syndrome (WS) (mean chronological age: 8;9 years; mean mental age: 4;8 years) and Down's syndrome (DS) (mean chronological age: 8;7 years; mean mental age: 4;6 years), matched individually on chronological age, mental age and performance IQ. The syntactic components…

Results demonstrated that when compared with normally developing children of the same mental age, the Down's syndrome Ss (6 to 12 years old) evidenced a more homogeneous pattern of syntactic usage and tended to acquire only low-level syntactic structures, as identified by the Developmental Sentence Scoring procedure. (Author)

This study, involving 48 children and adolescents with Down's syndrome, found that chronological age and mean mental age collectively accounted for much of subjects' variability in vocabulary comprehension and syntax comprehension, with total passes on a hearing screening accounting for additional variability. (Author/DB)