EEG MICROSTATES ANALYSIS IN PATIENTS WITH EPILEPSY

Analysis of EEG microstates is a promising topographical method that is currently being studied for diagnosis of neuro-psychiatric diseases such as schizophrenia, dementia, etc. The aim of our study is to describe the possibility of using the microstate analysis of electroencephalographic recordings (EEG) for examination of the epileptic activity. The EEG recordings were measured on patients with epilepsy and on control subjects (with no epileptic pathology) in the system 10 - 20. The data are analysed in average montage and filtered with bandpass from 0.5 to 30.0 Hz. We calculate the global field power (GFP) curve to extract microstates from the EEG recordings. We take local maxima (peaks) of GFP curve to create amplitude topographic maps. The microstate 1 seems to have higher occurrence for the non-epileptic controls than the patients with epilepsy. The duration of the microstate 4 seems to be higher in the epileptic patients than the non-epileptic controls. We have found that there is a significant difference in the duration, occurrence and contribution of the amplitude topographic maps between the non-epileptic controls and the patients with epilepsy.