Saccade adaptation in Williams-Beuren Syndrome.

PURPOSE To investigate the capacity for rapid saccade adaptation in Williams-Beuren Syndrome (WBS), a genetic neurodevelopmental disorder, in which it has been observed that saccadic accuracy is severely reduced. METHODS Saccade amplitude modification was elicited by backward steps (30% of target eccentricity) during the primary saccade in a classic saccade-adaptation paradigm. RESULTS Patients with WBS showed a significant decrease in saccade amplitude. Furthermore, we observed that higher saccade accuracy before adaptation was related to more adaptation. CONCLUSIONS The increased variability in motor performance does not abolish the ability for saccadic adaptation in subjects with WBS. Our results are congruent with the notion that part of the behavioral deficits observed in WBS may have a cerebellar origin.