Excessive transient muscle activity during REM sleep is most strongly associated with which disorder?

Excessive transient muscle activity during REM sleep is most strongly associated with which disorder?

• A. REM behavior disorder
• B. Rhythmic movement disorder
• C. Amyotrophic lateral sclerosis
• D. Obstructive sleep apnea disorder

Answer: (A)

Normal REM sleep includes muscle atonia to prevent movement. When excessive transient muscle activity occurs specifically during REM, it points to REM Behavior Disorder, because the loss of this REM atonia allows dream enactment with vigorous or complex movements. Rhythmic movement disorder tends to occur in children and involves repetitive movements outside of REM atonia loss, not a REM-specific phenomenon. Amyotrophic lateral sclerosis is a progressive motor neuron disease with weakness, not a sleep-stage–specific behavior. Obstructive sleep apnea involves airway obstruction and arousals across sleep stages, not prominent REM-related motor enactment.

Normal REM sleep includes muscle atonia to prevent movement. When excessive transient muscle activity occurs specifically during REM, it points to REM Behavior Disorder, because the loss of this REM atonia allows dream enactment with vigorous or complex movements. Rhythmic movement disorder tends to occur in children and involves repetitive movements outside of REM atonia loss, not a REM-specific phenomenon. Amyotrophic lateral sclerosis is a progressive motor neuron disease with weakness, not a sleep-stage–specific behavior. Obstructive sleep apnea involves airway obstruction and arousals across sleep stages, not prominent REM-related motor enactment.