HIGH FREQUENCY OSCILLATIONS DYNAMIC IN EPILEPTIC SEIZURES RECORDS

Abstract

Epilepsy is a chronic neurological disease that affects 1 in 200 people. In 30 \% of those affected there is a negative response to drug treatment, called this type refractory epilepsy, which are indicated as treatment surgical intervention. Its success consists in finding the cortical area responsible for the generation of crisis, called the epileptogenic zone.
In this work, the electrical record of this area in a patient with refractory epilepsy was studied in order to discern the oscillatory mechanisms underlying the epileptic process and to study the intrinsic dynamics of brain oscillations in the high frequency range. Neural activity was recorded for the baseline and preictal periods corresponding to a crisis using intracerebral electrodes implanted in the patient to achieve greater resolution of the local field potential.
When estimating the frequency spectrum using the Fourier transform for oscillation bands from 0.1 Hz to 50 Hz and from 50 Hz to 500 Hz (called high frequency oscillations), it was observed that the latter are very important in the epileptic phenomenon since they present a much more complex frequency structure in the preictal period compared to the baseline.