Abstract
The study focused on separation of sleep electroencephalogram (EEG) of patients
after ischemic stroke and sleep EEG of healthy subjects. A prognostic value of the
characteristics as regards patients' recovery was also studied. Many spectral measures and
measures of complexity and interdependence were evaluated for EEG of 50 patients and 52
healthy subjects. The patients had higher sleep efficiency, and they spent more time in slowwave
sleep (SWS) but less time in rapid eye movement sleep in comparison to controls.
During waking, high delta power relative to the reduced power of alpha and faster waves was
found after stroke. During SWS, on the contrary, fewer delta waves and more of faster waves
was observed in EEG of patients as compared to controls. The complexity of EEG of patients
was lower during wake and higher in SWS in comparison to healthy subjects.
Interdependence between the hemispheres was found to be lower for the sleep EEG of
patients. It was also found that, the lower relative power in 4-8 Hz and higher relative power
in 30-40 Hz of EEG 5-7 days after stroke, the worse prognosis regarding withdrawal of
symptoms within the next 90 days.
Go back