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Tonic activity of submental muscle denoted indicating REM sleep without atonia (polysomnogram)

A polysomnographic recording of increased REM tonic activity (denoted by purple arrow) in chin EMG lead for greater than half of the 30-second epoch. (Contributed by Dr. Muna Irfan.)

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  • Multiple sclerosis
  • Multiple system atrophy
  • Narcolepsy
  • Nightmare disorder
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  • Shy-Drager syndrome
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  • Synucleinopathies
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