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Normal REM sleep (polysomnogram)

Normal REM sleep in a 12-year-old girl. The EEG shows low-voltage irregular activity, mainly in the 2 to 7 Hz range, without spindles or K-complexes. Chin EMG shows muscle atonia with irregular phasic twitches and isolated potentials. Several rapid eye movements are apparent as rapid deflections in opposite directions in channels 1 and 2. (Contributed by Dr. Michael Aldrich.)

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