RELATION BETWEEN ELECTROENCEPHALOGRAPHIC AND HISTOLOGIC CHANGES FOLLOWING THE APPLICATION OF GRADED FORCE TO THE CORTEX

Abstract

THE electroencephalographic effects of trauma to the brain have been studied by a number of investigators. Williams and Denny-Brown,¹among others, have shown that a pathologic condition is indicated by the presence of slow waves of increased amplitude following a blow on the skull. These effects were produced experimentally on cats. The pathologic changes in the various cytologic elements following injury to the brain have also been studied by a number of investigators. The recent work of Rand and Courville describes in detail such histologic changes.² The present experiments were designed to investigate the possible relationship between the electroencephalographic patterns and the histopathologic changes occurring simultaneously after the application of graded force to the cortex. In order to investigate these changes a specially designed apparatus was used. MATERIALS AND METHODS Apparatus. —The traumatizing element (fig. 1AandB) consists of an electromagnet with a hinged armature tuned