Modulation of Inhibition and the Transition to Seizures

  • Marc A. Dichter


Understanding the mechanisms which underlie the transition between interictal and ictal activity is one of the most critical issues in the study of epilepsy. In all forms of epilepsy, the electrical activity in most parts of the brain is normal most of the time. A seizure occurs when neurons in many parts of the brain, including those parts which are normal, develop synchronized activity. In primary generalized epilepsy, the transition between interictal and ictal activity occurs abruptly and without obvious behavioral or electrophysiological warning. In focal epilepsy, the transition appears to occur first in a focal area of abnormality and then spreads to both adjacent and distant areas of normal brain. The phenomena which occur at the cellular level during such transitions have not been well characterized in either the human epilepsies or in most animal models of epilepsy, and therefore relatively few hypotheses have been developed to explain the transition to seizure.


Cortical Neuron Epileptiform Activity Inhibitory Synapse Focal Epilepsy Repetitive Activation 
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© Springer Science+Business Media New York 1988

Authors and Affiliations

  • Marc A. Dichter
    • 1
  1. 1.Department of NeurologyThe Graduate Hospital and The University of PennsylvaniaPhiladelphiaUSA

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