TEMPORAL PRIORITY OF PREMOTOR CORTEX OVER NEARBY AREAS IN RECEIVING VISUAL CUES IN PRIMATES

Neuronal activities in the premotor cortex (PM), supplementary motor area (SMA), and precentral motor cortex (MC) were recorded while monkeys performed a visually triggered task. Kendall's partial correlation coefficient analysis was applied to the data, to determine whether changes in neuronal activity were dependent on visual-stimulus or movement-onset. The proportion of cells in which neuronal activity changes were significantly related to visual-stimulus was 22% in PM cells, 7% in SMA cells, and 0% in MC cells. The sampling populations for visual-stimulus related coefficients were greatest in PM, followed by SMA, then MC. These results indicate that the PM has temporal priority over the SMA and MC in the receipt of visual cues.