Improvement in cognitive and language skills from preschool to adolescence in autism.

This paper reports on the developmental progression of a sample of 48 adolescents and young adults with autism who were previously assessed at preschool age and again in the mid-school period. In contrast to the earlier period when about one-third of the children made dramatic gains, cognitive and language skills tended to remain stable or decline over this time span. The gain in mental and language age of the non-retarded adolescents with autism was less than half the change in their chronological age. The mentally retarded adolescents with autism showed some gain in mental age over time but this was far less than their change in chronological age, and they showed almost no gain in language age. Early childhood predictors of language skills in adolescence were functional play skills, responsiveness to others' bids for joint attention, and the frequency of requesting behaviors.