Modality of data processing in Italian subjects with William Syndrome (WS)

Williams Syndrome (WS) is a rare genetic condition, characterized by mental retardation and a specific deficit in spatial abilities. A particular modality of data processing, clearer in many spatial tasks, has been noted in WS subjects: the tendency to process the individual details separately instead of as a whole («analytical modality»). A similar tendency is apparent in adults with right cerebral lesions. The opposite pattern («global») has been noted in subjects with Down Syndrome : the tendency to process the whole instead of the details, as commonly found in adults with left cerebral lesions. In a wider multidisciplinary research on WS, the global/analytical modality of data processing is examined in 5 italian children with WS and 5 children with mental retardation from various causes. The mean C. A. of WS subjects was = 11 years and 10 months, and their M. A. was = 5 years and 6 months. The mean C. A. of control subjects was = 11 years and 10 months, their mean M. A. was = 6 years. The following tests have been administered: Hierarchical Stimuli (Stiles), Rey Complex Figure Test-form B, Visual-Motor Integration Test, Block Design (WISC-R) and Block Construction (Stiles). Mental age was assessed by Leiter International Performance Scale. Using the Hierarchical Stimuli scores the Mann Withney U Test was conducted to compare the two groups. The results were not significant, in either global or local levels. Morever, a qualitative analysis of the performance of some subjects in the tasks of copying shows a great variability among them. Therefore this study does not confirm the analytical modality of data processing as characteristic of this sample of WS subjects. It is possible that further sudies in larger sample would confirm this data.