Functional and Structural Changes in the Monkey's Brain During and After Concussion

Abstract

Concussion was produced by hydraulic or pendulum technics. Electrodes were placed in the brain and physiologic changes observed. Formalin fixation and buffered thionin staining were used for histologic results. Functions of the motor cortex were more adversely affected than was function of cranial motor nuclei, e.g.: although corneal reflex abolished, threshold of facial motor nucleus for eyelid closure was unchanged. Chromatolysis was observed in certain irterneuron systems of the brain stem. Other changes were seen in pyramidal cells of the motor cortex. Primary motor neurons of the brain stem were not affected.