What is a common clinical feature of REM sleep behavior disorder (RBD)?

A common clinical feature of REM sleep behavior disorder (RBD) is acting out dreams. In individuals with RBD, the usual muscle atonia that occurs during REM sleep is absent, which allows for physical movements that can mirror the actions performed in their dreams. This can lead to various behaviors, such as kicking, punching, or other vigorous movements, making it a distinctive characteristic of the disorder. Patients often have vivid recall of their dreams which typically involve action-packed or violent scenarios, and this disinhibition of motor control during REM sleep sets RBD apart from other sleep disorders.

The other options do not accurately describe RBD in the same way. Sleepwalking typically occurs in non-REM sleep rather than REM sleep, making it distinct from RBD. Vocalizations can occur during dreams, but they are not as specific to RBD as the physical enactment of dreams. Sleep apnea is a separate condition characterized primarily by disruptions in breathing during sleep, and it is not related to the dream enactment seen in RBD.