Which feature is associated with REM Sleep Behavior Disorder?

REM Sleep Behavior Disorder (RBD) is characterized by inappropriate behaviors that occur during REM sleep, the sleep stage associated with dreaming. Individuals with RBD may demonstrate vocalizations, such as talking or shouting, and exhibit vigorous motor movements while they are still asleep. This is in contrast to the usual muscle atonia that normally accompanies REM sleep, which prevents individuals from acting out their dreams.

The presence of vocalizations and motor movements is specific to RBD and highlights the dysfunction of the mechanisms that typically allow REM sleep to be a state of atonia, thus leading to the enactment of dreams, which can sometimes be violent or aggressive. Understanding this characteristic helps differentiate RBD from other sleep disorders, such as sleepwalking or non-REM sleep disorders, which involve different patterns of behavior and occur in different sleep stages.