By adulthood, most males with fragile X syndrome (FXS) require support to navigate day-to-day settings. The present study cross-sectionally: (1) characterized the profile of daily living skills in males with FXS and (2) examined associated participant characteristics (i.e., fragile X mental retardation protein [FMRP] expression, nonverbal…

Numerous studies have investigated the predictors of language in pre-verbal toddlers and verbally fluent children with autism spectrum disorder (ASD). The present study investigated the concurrent relations among expressive language and a set of empirically-selected social communication variables--joint attention, imitation, and play--in a unique…

Purpose: Summarizing expository passages is a critical academic skill that is understudied in language research. The purpose of this study was to compare the quality of verbal summaries produced by adolescents for 3 different discourse types and to determine whether a composite measure of cognitive skill or a test of expressive syntax predicted…

Many males with FXS meet criteria for ASD. This study was designed to (1) describe ASD symptoms in adolescent and young adult males with FXS (n = 44) and (2) evaluate the contributions to ASD severity of cognitive, language, and psychiatric factors, as well as FMRP (the protein deficient in FXS). A few ASD symptoms on the ADOS-2 were universal in…

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…

Background: Girls with fragile X syndrome (FXS) have a wide range of cognitive and language abilities. The range of language outcomes experienced by girls with FXS, however, has been relatively unexplored. The purpose of this exploratory study was to examine receptive and expressive language, with a focus on vocabulary and syntax, in a group of…

Social interactions can be a source of social stress for adolescents. Little is known about how adolescents with developmental difficulties, such as specific language impairment (SLI), feel when interacting socially. Participants included 28 adolescents with SLI and 28 adolescents with typical language abilities (TL). Self-report measures of…

Predictors of language production skills were evaluated in 48 children and adolescents with Down syndrome and compared to 48 children matched for nonverbal mental age and mother's years of education. Comparison of two models found the model that incorporated comprehension performance (as well group membership, chronological age, cognition,…

Children and adolescents with Down syndrome show an emerging profile of speech and language characteristics that is typical of the syndrome (Chapman & Hesketh, 2000; Chapman, 2003; Abbeduto & Chapman, 2005) and different from typically developing children matched for nonverbal mental age, including expressive language deficits relative to…