UNIQUE PROFILE OF VISUO-PERCEPTUAL SKILLS IN A GENETIC SYNDROME

Williams syndrome (WS) and Down syndrome (DS) are genetic disorders wi th characteristic neuropsychological profiles. Subjects with WS show s urface similarities to subjects with right hemisphere damage (RHD) in their relative preservation of linguistic skills, their poor visuo-con structive skills, and their hierarchical processing biases. Ten adoles cents and young adults with WS acid nine matched subjects with DS were administered a battery of visuospatial perceptual tasks to test wheth er the profile of performance in WS would resemble that in RHD. It was found instead that the WS subjects showed a distinctive clustering of skills, with particular preservation of facial discrimination, but im pairment of other perceptual skills. Subjects with DS showed a more ho mogeneous profile. The WS profile may map onto the functional dichotom y between ventral and dorsal visual pathways in the cerebral cortex. ( C) 1995 Academic Press, Inc.