Abstract
It has been hypothesized that a local processing bias underlies overall visuospatial impairments in Williams syndrome (WS). However, recent studies have challenged this hypothesis by providing evidence against a local processing bias at the perceptual level. The aim of the present study was to further examine drawing and perceptual skills in children with WS using closely matched-hierarchical stimuli. In the drawing task children with WS exhibited a local processing bias. However, no significant preferential bias was found in the perceptual task. This indicates that children with WS do not systematically present a preferential bias for local information. Taken together the findings of the present study suggest that perceptual processing deficits per se are unlikely to explain local processing biases in visuoconstructive tasks often described in people with WS.
We are grateful for the collaboration of the French Williams Syndrome Associations (Associations du Sud Est and Rhone Alpes) and thank the children and their parents for participating in the study. We also thank helpful comments from anonymous reviewers in the preparation of this manuscript.
Notes
1A pilot study revealed that typically developing children individually matched to participants with WS on chronological age performed at ceiling level in the drawing task. Thus, only mental-age-matched controls were included in this study.
2The number of global choices was calculated by subtracting the number of local choices from the total number of trials (N = 36). Thus, if the number of global choices did not result from chance, then it should be significantly different from the number of local choices.