Oculomotor Function Following Cerebral Hemidecortication in the Monkey

The role of the primate cerebral cortex in oculomotor function has been extensively investigated with electrical stimulation techniques. Recent experiments have demonstrated that deviational (horizontal and vertical), and centering eye movements may be elicited upon stimulations from almost every point on the cortex or subcortex. In the alert preparation, such as monkeys with cervical transection or chronically implanted electrodes,¹²,²²the evoked ocular movements are usually of the deviational type. As a rule the binocular movement is horizontal and contralateral in direction. In the occipital lobe, vertical or oblique movements are more frequently obtained than from other areas of the brain.²⁰Electrical stimulation in the anesthetized preparation, in contrast, induces more of eye centering; horizontal movements are less frequent, and vertical are rare.¹¹These observations suggest that the entire cerebrum influences oculomotor function. In man, there seems to be some cortical specificity for ocular responses. Electrical stimulations elicit