A SECOND MOTOR CORTEX IN THE MONKEY

Publisher Website
Google Scholar
Abstract
The authors describe a 2d motor cortex in the monkey; this lies on the lateral (exposed) and medial (buried) walls of the fronto-parietal operculum and the posterior portion of the insula. The arrangement of body-parts in this area is roughly that of the arrangement of the 2d sensory cortex which lies posteriorly overlapping the motor cortex. The face region is anterior-superior and comes onto the lateral hemispheric surface. The foot region is posterior-inferior, adjacent to the supratemporal plane. The hand region, by far the largest, lies between the others. The movements obtained with 4/sec. stimulation are individual isolated ones. Those from the distal portions of the body are much more readily obtained than those from the proximal portions. In all cases, the movements are contralateral to the area stimulated. Stimulation of the anterior half of the insula caused respiratory slowing and arrest in expiration. Movements of the vocal cords were obtained from operculum anterior to the inferior precentral dimple. Eye movements are obtained from the anterior-superior portion of the insula near the intrafrontal plane. Stimulation of the posterior third of the superior (buried) surface of the middle temporal gyrus produces ipsi-lateral twitches of the pinna; stronger stimulation causes spread to other muscles innervated by the facial nerve.

This publication has 2 references indexed in Scilit: