Syntax and its interfaces at the low and high ends of the autism spectrum

Studies on the language abilities in autism spectrum disorders (ASD) have tended to include individuals across the spectrum, with the consequence that the ensuing picture is rarely clear. Most recent studies setting apart individuals at the lower end of the autism spectrum have discovered severe problems in certain areas of grammar. Investigation of grammatical abilities at the higher end of the spectrum has not identified severe problems so far, in an interesting contrast with the lower end. Here we report on current research on pronominal object clitics and their counterpart DPs, which demonstrates that, in some syntactic environments, high-functioning children with ASD fall behind typically developing children. We claim that this behavior does not reflect problems with syntax proper, but is a consequence of pragmatic shortcomings with consequences for the syntax-pragmatics interface. Errors of substitution of clitics with their corresponding DPs are likely to be caused by difficulties in detecting prominence in the discourse. Difficulties with Focused DPs are likely to be caused by problems in distinguishing old from new information and its mapping to prosody. Future research needs to investigate pragmatics, syntax and prosody independently, in order to reach solid conclusions regarding their interaction with respect to specific phenomena in autism, which, in turn, provides an ideal condition to test the contribution of each domain to these phenomena.