DO INDIVIDUALS WITH WILLIAMS-SYNDROME HAVE BIZARRE SEMANTICS - EVIDENCE FOR LEXICAL ORGANIZATION USING AN ONLINE TASK

Williams syndrome, a neurodevelopmental disorder, has attracted a grea t deal of debate concerning the purported intactness of language in th e face of other serious cognitive deficits. As more in-depth studies o f specific aspects of WS language have emerged, the notion of a preser ved language module has been seriously challenged. Although WS vocabul ary scores are often impressive, several investigators have claimed th at WS semantics are aberrant. All studies hitherto have been based on off-line experiments which necessarily involve metalinguistic processe s. This clearly affects the performance of individuals with cognitive deficits. We report here an on-line study probing the semantic structu re of the WS lexicon, using a task - semantic priming - which minimise s metalinguistic demands. We show that WS subjects display the same ta xonomic/category and thematic/functional priming effects as normal con trols. The results are discussed in terms of the differences between r eceptive and expressive language, as well as the fact that although se mantic memory and the automatic access to semantic information for ind ividual words is normal in WS, the integration of semantic information into sentence comprehension may be abnormal. The importance of online tasks to highlight such differences is stressed.