Hippocampal oscillatory patterns during working memory in epileptic patients

Rationale: Theta oscillations are thought to mediate memory processing in the hippocampus. We examined oscillatory patterns in the human hippocampus and correlated oscillatory power with pathology and IQ. Methods: During a working memory task (Sternberg task) oscillatory pattern in the hippocampus were recorded utilizing bilateral depth electrodes in eight epileptic patients. Patients were enrolled while undergoing epilepsy surgery. Trial averaged spectrogram and power spectrum were calculated after differentiating the signal to eliminate 1/f noise. Results: Oscillatory patterns and power spectra could clearly d…