Global spatial organization by individuals with Williams syndrome

Williams syndrome is a genetically determined disorder with a characteristic cognitive profile. Overall IQ tends to be lower than in the normally developing population, performance on measures of linguistic ability is somewhat higher than would be expected given the levels of IQ typical for this group, and there is a particular weakness in visuospatial construction (e.g., block design tasks). A well-known hypothesis about the deficit in visuospatial construction is that people with Williams syndrome are strongly inclined to be focal spatial processors. We report a test of this hypothesis that used a visual search task sensitive to spontaneous global spatial organization A sample of adults with Williams syndrome produced a pattern of data demonstrating that they spontaneously organize spatial displays at a global level. Indeed, individuals with Williams syndrome found it more difficult to change from global to local processing than participants with normal intelligence. We suggest that the primary problem with visuospatial construction in people with Williams syndrome is not in the salience of single levels of organization but rather in the difficulty of changing between organizations.