Electroencephalographic Classification of the Epilepsies

The demonstration that specific patterns of electrical discharge from the brain, recorded through the unopened skull, are related to epileptiform disorders of cerebral function has given a new approach to the diagnosis, treatment and general understanding of the nature of the epilepsies. Different forms of electrical disturbance have been found with different forms of clinical seizures, so that the electroencephalogram has given a new basis for classification. The validity and possible significance of such a classification of the epilepsies form the subject of the present report. Gibbs, Davis and Lennox1first observed a characteristic form of electrogram2with petit mal attacks distinct from that obtained during grand mal attacks. Later Gibbs, Gibbs and Lennox3discovered still another pattern of waves to characterize the electrogram during epileptic equivalent states or automatisms, which they prefer to call psychomotor attacks. These three forms of epileptic discharge are described as follows