Electrical Activity of the Hippocampus of Patients with Temporal Lobe Epilepsy

Abstract

<h3>Introduction</h3> The electrical activity of the hippocampus and related structures in animals has been extensively investigated in recent years. Certain studies have shown that the hippocampus has a relatively lower threshold for local and propagated seizure discharges than the isocortex. Further, a high tendency of background electrical activity of the hippocampus toward synchronization has been found. The pertinent literature has been reviewed by Kaada,¹³Cadilhac,²and Creutzfeldt.³Recently, electrophysiological observations have been made on the intraventricular surface of the cornu ammonis in epileptic patients. Passouant and his associates²³have analyzed the after-discharges of the cornu ammonis induced by electrical stimulation in 14 cases in the course of hemispherectomy or temporal lobectomy. Later, they reported on hippocampal corticography in the waking state and related the results to the histological findings in four epileptic patients treated by hemispherectomy.²⁵Kellaway¹⁶made recordings from the scalp and the