Seizure Termination in Neural Network Models of Neocortical Neurons
Piotr J. Franaszczuk, Gregory K. Bergey, Pawel Kudela
Department of Neurology, Johns Hopkins University School of Medicine and Epilepsy Center, Johns Hopkins Hospital , Baltimore, Maryland U.S.A.
RATIONALE: Epileptic activity terminates spontaneously, typically lasting only seconds or minutes. In addition synchronous epileptiform activity often terminates spontaneously in all local regions. The actual mechanisms for this spontaneous termination are not well established. We have studied burst termination in model neural networks previously shown to have characteristics similar to neocortical neuronal assemblies.
METHODS: Networks up to 62,500 neurons were modeled based on the modified Av-Ron/Rinzel model for single neurons. Each neuron had two excitatory connections per neuron, but not inhibitory inputs.
RESULTS: In this restricted model of neuronal networks, a synchronous burst ended spontaneously and in many instances, the pattern of cessation was one of termination in all channels rather then in isolated network regions.
CONCLUSIONS: Models of neuronal networks can be developed that reveal patterns of seizure termination. Simultaneous or near-simultaneous cessation in all regions can be modeled in networks that do not have synaptic inhibition. Seizure termination may therefore not require intact synaptic inhibition but may depend upon other membrane or network characteristics.
(Supported by the Epilepsy Foundation , NIH NS 38958-01,and NIH NS 33732-01)
Epilepsia Vol. 40, (Suppl. 7): 12, 1999