Location: Fields Institute

March 15, 2011 - 3:30 p.m.
Professor John Milton, Claremont College
Multistability and the onset of epileptic seizures

An understanding of phenomena that occur at the edge of stability may provide important clues for both the detection of impending seizures as well as their prevention. In this talk I discuss the effects of noise and time delay on switching between attractors in a bistable dynamical system. The discussion is motivated by a consideration of the timing of epileptic seizures in patients with nocturnal frontal lobe epilepsy. In this rare, familial form of epilepsy seizures occur only during sleep and most commonly during the transition between sleep stages I and II. Qualitative arguments and computer simulations of a bistable two-neuron network with delayed mutual inhibition are used to demonstrate that neural populations are particularly vulnerable for the production of paroxysmal transient events at times when changes between attractors occur. These paroxysmal events take the form of delay-induced oscillatory transients which can last orders of magnitude longer than the neural conduction delay. These arguments emphasize the importance of careful studies of the timing of seizure occurrences with respect to sleep stage transitions in patients with nocturnal frontal lobe epilepsy. This talk will be assessable to a broad audience.

Audio and slides of the talk

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