ELECTRICAL STIMULATION OF THE CORTEX CEREBRI OF CATS

Abstract

Although much has been done to advance knowledge of the effect of electrical stimulation of the cortex cerebri in various species of animals since the primary work in this field, interpretation of the results has been difficult because of the multiple factors for variation which appear in every experiment. One of the most potent influences for variation of responses to cortical stimulation is the state of anesthesia. During the exploration of cortices of normal cats we frequently observed that a state of lightness of anesthesia was accompanied by a lowered threshold to stimulation and, conversely, that when the cat began to make spontaneous movements because of the lightness of anesthesia and the ether supply was increased, it was immediately necessary to increase the strength of stimulus to produce the usual response from a point. The depth of narcosis could be made so great that the cortex failed to respond to