CORTICAL NETWORKS FOR VISUAL REACHING

The cortical anatomical substrates by which visual information may inf luence the frontal areas controlling reaching movements to visual targ ets were studied in monkeys. A reaching task was employed to character ize the arm-related regions of the frontal lobe. Injections of retrogr ade tracers into these physiologically defined cortical fields reveale d a gradient of parallel cortico-cortical pathways originating in the superior parietal lobule and impinging upon different frontal regions. These results support the hypothesis that the superior parietal lobul e can supply the frontal motor and premotor areas not only with the pr oprioceptive information but also with the visual input required for t he control of reaching.