Epileptic Focus Location: Spectral Analysis Method

A spectral analysis technique for locating the site of an epileptic focus in the cat brain with the use of multielectrode data, obtained during a generalized seizure, is described. The data, indicating widespread appearance of epileptic activity, does not lend itself to conclusive analysis by conventional means. Three channels of data are examined at a time. One channel is said to drive the other channels if the first channel explains or accounts for the linear relation between the other two over a frequency interval corresponding to the interval of greatest energy concentration. The method of analysis involves computation of the coherence and partial coherence between data from all electrode pairs.