Description
Williams syndrome (WS) is a rare genetic disorder characterized by a deletion of about 20 genes including the elastin gene on chromosome 7. Individuals with WS have a uneven cognitive profile as adults: they are mildly to moderately retarded with significantly impaired visuo-spatial skills, however, language is a strength and they show a characteristic behavioral profile of extremely sociable and friendly personalities. In spite of the late onset of language in WS as children, they later develop a robust vocabulary similar to mentally age matched typically developing children. Interestingly, they do not appear to follow the typical path of language development. In typical development, a link has been noted between language development and earlier development of nonverbal communicative tools such as gestures, eye gaze, joint attention, and social referencing. Current research suggests that children with WS do not produce many gestures, such as those seen in typical development, until after they have acquired language. Moreover, they may have difficulties in areas of social referencing as they often become fixated with unfamiliar faces. The purpose of the present study was to examine the production of nonverbal communicative behaviors of young children with WS and their relation to vocalizations. Participants included 12 children with WS and 30 typically developing controls matched on mental ages, as calculated by the Bayley Mental Development Index. All data were previously collected via video recording by Dr. Ursula Bellugi as part of the Project in Cognitive and Neural Development at UCSD. Nonverbal communicative behaviors were measured by means of tasks from the Laboratory Temperament Assessment Battery (Lab Tab). Four questions were addressed: (1) Do toddlers with WS produce nonverbal communicative behaviors? (2) If children with WS are producing nonverbal behaviors with communicative intent, what do these behaviors look like? (3) Provided children with WS produce nonverbal communicative behaviors, will such behaviors co-occur with vocalizations? (4) Will children with WS look more at a person than an object? In exploring such questions, the present study sought to explore the overall question: Do children with WS use nonverbal forms of communication during language development similar to children of typical development? Results suggest that when including a more broad range on nonverbal behaviors, children with WS do produce nonverbal behaviors with communicative intent.
