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Electrophysiology of the Interictal-Ictal Transition in Humans

  • Michael R. Sperling

Abstract

Since the discovery of the spike in the EEG by Gibbs and colleagues in 1935, cerebral electrical activity has been the subject of intensive investigation in the study of epilepsy. The focus of most investigators has been upon abnormalities seen in the interictal state, the examination of seizures being limited to relatively few specialized laboratories. Early studies of the transition from the interictal to the ictal state characterized amplitude and frequency changes in the EEG, and while attention was paid to underlying mechanisms, in humans, a decided emphasis has been placed upon localization of a seizure focus for purposes of resective surgery (1,27,29,31,55,67,92). Key features of the ictal state, compared with the interictal state, are the capacity for development of self-sustaining discharges and spread to other cortical and subcortical areas. The purpose of this discussion is to review the electrophysiologic features in focal epilepsy of the transition from interictal to the ictal state.

Keywords

Temporal Lobe Temporal Lobe Epilepsy Ictal Onset Seizure Focus Complex Partial Seizure 
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© Springer Science+Business Media New York 1988

Authors and Affiliations

  • Michael R. Sperling
    • 1
  1. 1.Department of NeurologyThe Graduate Hospital University of PennsylvaniaPhiladelphiaUSA

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