Prosodic expression of contrast in Williams syndrome

Williams syndrome (WS) is a unique genetic developmental disorder characterized by excessive social behaviour accompanied by exaggerated prosody. While past studies with off-line assessment of prosodic skills report significant delays in prosodic skills in individuals with WS as compared to typically developing controls, reports typically lack speech analysis. The current study, using a speech elicitation task, tests whether individuals with WS can express contrast with prosody and what phonetic cues they produce to signal contrast. The data from 10 WS and 10 chronological-age (CA) matched control participants demonstrate striking similarities in their use of duration and intensity to express contrast. However, F0 did not systematically mark contrast in the WS group. The present data confirm the sensitivity to words’ discourse status and the ability to mark contrast in WS, and suggest that the past low ratings of prosodic skills in WS may reflect the lack of reliable F0 cues.