Longitudinal analyses of expressive language development reveal two distinct language profiles among young children with autism spectrum disorders.

Although children with autism spectrum disorders (ASD) show significant variation in language skills, research on what type(s) of language profiles they demonstrate has been limited. Using growth-curve analyses, we investigated how different groups of young children with ASD show increases in the size of their lexicon, morpho-syntactic production as measured by Brown's 14 grammatical morphemes, and wh-question complexity, compared to TD children, across six time points. Children with ASD who had higher verbal skills were comparable to TD children on most language measures, whereas the children with ASD who had low verbal skills had flatter trajectories in most language measures. Thus, two distinct language profiles emerged for children with ASD.