Expression des états mentaux chez les enfants atteints du Syndrome de Williams : analyse d'interactions collaboratives mère-enfant

People affected by Williams syndrome (WS), a rare genetic disease, are characterized by a personality noted for its “hypersociability” along with relatively spared language in the face of significant cognitive deficit. Our research focuses on the intersection of two domains by examining linguistic markers of this sociability: how do children with WS perform in a collaborative interaction? Do they express mental states, how and what kind? And do they answer to the mental states expressed by others? We present data from three matched groups of 12 each: children with WS, children with Down syndrome (DS) and control group (CO) in a task in which the mother and child interacted in a standardized collaborative situation with a social stake (a precise aim to reach). The children with WS had comparable difficulties to those with DS in the interaction: they produced fewer turns and fewer utterances than controls. Children with WS produced more expressive mental states than either the DS or CO group. The WS children had more difficulties cooperating than did either the DS or CO children: the unrealized requests by the children are more numerous in the WS group. Thus in a collaborative interaction, the children with WS present a unique profile: difficulty in maintaining and participating in the interaction contrasting with a facility in expressing mental states about feelings and emotions.