: Good slides often use "montages" that combine EEG with EOG (eye movement) and EMG (muscle tone) data, which is necessary to identify REM sleep accurately.
| Rhythm | Frequency | State | | :--- | :--- | :--- | | Beta | 13-30 Hz | Awake, alert, anxious | | Alpha | 8-13 Hz | Awake, relaxed, eyes closed | | Theta | 4-8 Hz | Light sleep (N1), drowsiness | | Delta | 0.5-4 Hz | Deep sleep (N3), regeneration | eeg and sleep physiology ppt