Histogram of 12 sleep features in Wake, N1, N2, N3, and REM stages of 30 PSG data.

Abstract

The X-axis represents the normalized feature values and the Y-axis represents the number of epochs. Features are power: (A) 0–30 Hz EEG, (B) 0–30 Hz EMG; power ratio: (C) 0–4 Hz / 0–30 Hz EEG, (D) 8–13 Hz / 0–30 Hz EEG, (E) 22–30 Hz / 0–30 Hz EEG; power (F) 0–4 Hz EOG; spectral frequency: (G) 0–30 Hz mean frequency EEG, (H) 0–30 Hz mean frequency EMG; duration ratio: (I) alpha ratio EEG, (J) Spindle ratio EEG, (K) SWS ratio EEG; amplitude: (L) mean amplitude EMG.</p