1WILLIAMS SYNDROME: AN UNUSUAL NEUROPSYCHOLOGICAL PROFILE

3As a genetic experiment of nature, Williams syndrome (WMS) is expressed on multiple biological levels. Ultimately, WMS presents an unusual neurobehavioral profile, affording the opportunity to study both neurobiology and neuropsychology within a single, genetically-defined paradigm. The Salk Institute's Laboratory for Cognitive Neuroscience (LCN) has been engaged in a comprehensive program of study which spans multiple biological levels in WMS. These levels include the linguistic, the neuropsychological, the neuroanatomic, the neurophysiologic, and the genetic. The fundamental goal of these combined investigations is to help elucidate the brain bases of behavior. In this chapter, we present first the unusual neuropsychological profile of WMS, a profile of peaks and valleys of abilities within and across domains of higher cognitive functioning. We then review the results of recent studies on the neuroanatomic basis of WMS and its neurophysiological characteristics, and the implications of this research program for an understanding of the neural systems that subserve language and cognitive functioning. A more complete discussion of the neuroanatomic and neurophysiologic investigations in WMS is presented in the chapters which follow. Importantly, these cross-disciplinary studies all are carried out on the same subjects, and thus give us the unusual opportunity to relate findings from cognitive, neuroanatomical and neurophysiological levels