Abstract View EXTRACELLULAR POTASSIUM DYNAMICS CONTROLS TRANSITIONS BETWEEN FAST AND SLOW SEIZURE-LIKE OSCILLATIONS
Computational models of cortical networks were used to investigate the effects of extracellular K+ dynamics on seizure-like synchronous oscillatory activity similar to that observed in anesthetized cats in vivo and during LennoxGastaut types of seizures in humans. Active and passive K+ transport through the cell membrane, glial buffering, and diffusion in the extracellular space were included in the model. In a single cell, increase of [K]o caused slow (2-3 Hz) periodic bursting; progressive decrease of [K ]o triggered a switch to fast (~10 Hz) oscillatory firing (fast run). The cell eventually returned to its resting potential. In a network of cortical