Epoch Parameterization by Gabor Atom Density in Experimental Epilepsy

An Electrocorticogram (ECoG), during an epilepsy episode can change dramatically from the normal state into a high amplitude low frequency signal and suddenly return to the normal sate. It is possible to identify some stages in the epilepsy seizure, the most representative of them: basal, preictal, ictal and posictal. ECoG are highly non periodical signals, so they are analyze with T-F algorithms, in order to follow up its frequency evolution through the seizure stages. Each seizure stage has different frequency components and they show up at different time. Experimental epilepsy produce by kindling model in rats is used; signals are recorded at cortex level. The ECoG is decompose by means of the Matching Pursuit algorithm into Gabor atoms, so the Gabor Atom Density could be a measure of the epoch, which tell us if an epoch from an ECoG belong to one of the four seizure stages.