Frequency flow dynamics of epileptic brain.

Epilepsy affects 1%-2% of the general population, almost 50% of whom are medically refractory and poses a huge burden. A device can possibly be designed for responsive brain stimulation of the epileptogenic focus for seizure control but optimal seizure detection patterns and stimulus parameters are not yet determined. To explore the possibility of identifying a signature prior to the seizure, we studied the dynamic evolution of frequency from electroencephalography (EEG) of three patients with partial epilepsy using the method of frequency flow. We found that prior to seizure, the frequency flow dynamics exhibit a buildup of 5-12 Hz activity which remains high during the initial stage of the seizure with a characteristic time constant and may be used for seizure detection and/or anticipation. We conclude that dynamics of frequency flow in the 5-12 Hz range can be a potential marker for the detection and/or the anticipation of the seizure in temporal lobe epilepsy.