ROLE OF THE LEFT AND RIGHT SUPPLEMENTARY MOTOR AREAS IN MEMORY-GUIDEDSACCADE SEQUENCES

Six right-handed patients with a lesion affecting the left (3 patients ) or right (3 patients) supplementary motor area were studied using si ngle and sequential memory-guided saccade paradigms. Accuracy of singl e saccades was preserved in both groups, compared to control subjects, and the chronology of saccade sequences was disturbed in the group wi th the left lesion but not in the group with the fight lesion. The res ults suggest that neither side of the supplementary motor area is invo lved in spatial memory, and that the left supplementary motor area pla ys a greater role in motor sequencing than does the fight supplementar y motor area.