Correlations between the electroencephalogram and cortical histochemical changes in experimental brain lesions

Abstract

The relationship of EEG findings, histochemical data on glycogen, and oxidative enzymes (DPN-diaphorase) were studied in experimental cortical lesions in the guinea pig. There was a correlation between more than 50 per cent decrease of oxidative enzyme reaction in cortical tissues, the deposition of glycogen in the tissue, and the appearance of slow-wave activity in the EEG. Slow-wave activity was related to the presence of tissue showing almost normal cell population but markedly decreased enzyme reaction; decrease of enzyme activity in necrotic cortical tissue was without significance for the appearance of slow waves. The significance of these data for the interpretation of a delta focus in the human EEG was discussed, based on histochemical and EEG data from forty-four neurosurgical human biopsies.