This longitudinal study examined pragmatic language in boys and girls with Down syndrome (DS) at up to three time points, using parent report, standardized and direct assessments. We also explored relationships among theory of mind, executive function, nonverbal mental age, receptive and expressive vocabulary, grammatical complexity, and pragmatic…

Whereas pragmatic language difficulties are characteristic of both autism and Fragile X syndrome, it is unclear whether such deficits are qualitatively similar or whether certain skills are differentially affected. This study compared narrative competence in boys with autism, Fragile X syndrome, Down syndrome, and typical development. Results…

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…

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,…