Keywords: Williams syndrome, prosody, utterance, planning, syntax.
We present a preliminary investigation on prosody and complex syntax in a boy with Williams syndrome, one mental age matched control and one chronological age matched control. We aimed at verifying the existence of a deficit at the prosody/syntax interface in a language sample elicited by means of a conversational task. Results hint at a specific deficit in accessing syntax at sentence and discourse levels for the boy with Williams syndrome with respect to both controls. However, at a discourse level the boy with Williams syndrome seems to have developed an adaptive strategy in resorting to utterance juxaposition which makes his production superficially similar to that of the chronological age control, but which charges the communicative partner with the burden of inferring the appropriate implicit connection. Indices of prosodic fragmentation are of clinical relevance: they may account for the singsong intonation and suggest the existence of a planning and coordination deficit at the interface between the prosodic and linguistic components of the utterance process.