Fig. 4: Neurophysiological data: background EEG activity.
Selected results from ASEEGA algorithm (Physip®). On the x-axis: time of the polysomnography. On the y-axis, from top to bottom: time-frequency analysis of EEG (normalized power spectral density in dB), mean frequency of spindles per 30-seconds epoch, 5-class hypnogram. Results are presented for a healthy subject then for each patient. An illustration by raw EEG pages is provided for the most relevant patterns. A Patient 1 at T2: Abnormal wakefulness pattern with a pathological wake EEG on the left and an N3 period on the right (Delta dominant frequency corresponding to a slow wave sleep period). On the time-frequency analysis, the increase of Theta-Delta frequency during the prolonged wake period at T2 can be compared to the time-frequency analysis made on a 20-min EEG at T1 (predominant Alpha-Theta frequency without Delta rhythms) and to the pattern of the healthy subject. B Patient 2: Abnormal sleep-wake architecture with: i) prolonged periods of wake during the evening (on the left) and the night (around midnight for instance); ii) prolonged sleep periods during the day (N2 period in the middle) and the night (N3 period on the right). EEG bipolar montage, pages of 20 seconds, filters = 0.053 – 60 Hz, amplitude = 50 microV/cm. W = Wake N1-2-3 = Sleep stage 1-2-3 R = REM sleep Art: Artefacts
