Abstract
PURPOSE: Previous research has suggested that language comprehension might be particularly impaired in children with autism spectrum disorder (ASD), but this profile has been only broadly characterized. In the current study, the authors examined sentence comprehension in school-age boys with ASD, including a subgroup with intellectual disability (ID), with particular attention paid to errors that might differentiate between lexically and syntactically based difficulties. METHOD: Participants were boys with ASD (n = 45, ages 4-11 years) and younger typically developing boys (n = 45, ages 2-6 years). Comprehension was assessed with the Test for Reception of Grammar-Version 2 (TROG-2; Bishop, 2003). Error types were analyzed for a subset of items. RESULTS: Boys with ASD did not differ from younger typically developing boys matched on receptive vocabulary in overall sentence comprehension on the TROG-2 or the number of lexical errors committed. In contrast, the subgroup of boys with ASD and ID (n = 16) had poorer overall performance and committed more lexical errors than younger typically developing boys matched on nonverbal cognition. CONCLUSIONS: On average, comprehension was delayed in school-age boys with ASD but not beyond receptive vocabulary expectations. Boys with ASD and ID, however, had a weakness in sentence comprehension beyond nonverbal cognitive expectations.