Changes in the Cerebral Cortex Produced by Thermocoagulation

Recently the method of laminar thermocoagulation has been described1as a method of approach to the physiology of the various layers of the cerebral cortex. It was established that local application of moderate heat for short periods to the exposed surface of the cortex results in destruction of its nerve elements. "Dosing" the heat applied allows the limitation at will of the depth of the lesion to any number of consecutive cortical layers. Thus, application of 65 C. for two seconds destroys the two superficial layers, 70 C. for three seconds, the three outer layers, and 70 C. for four seconds, the four outer layers; application of 80 C. for five seconds destroys all the layers. For a description of the technic and of the necessary simple equipment we refer the reader to the papers already published.1In this communication we shall discuss the pathologic observations, especially some