Abstract
Previous studies have found that pediatric patients with resections of the ventral visual pathway retain mostly normal visuoperceptual abilities. It is not clear whether visuomotor computations, carried out by the dorsal pathway, follow a similar behavioral pattern. We examined visuomotor and visuoperceptual behaviors in a pediatric patient TC, who underwent a cortical resection that includes portions of the left ventral and dorsal pathways. TC used her right and left hands to estimate perceptually the width of blocks that varied in width and length, and, in a separate condition, to grasp the same objects across their width. Consistent with previous studies, TC’s perceptual performance was comparable to that of controls. In contrast, TC had reduced visuomotor sensitivity to object shape but only when she grasped the objects with her contralesional right (and not ipsilesional left) hand. These results provide evidence for a striking difference in the reorganization profiles of the two visual pathways. This difference might be attributed to a greater degree of hemispheric specialization of the dorsal pathway, as well as to differential maturation rates of the two pathways, such that the dorsal pathway maturation precedes that of the ventral pathway.