Rapid Eye Movement (REM in English) is a sleep phase that is characterized by rapid eye movements while they are closed. BAD for older people usually takes about 20-25% of the sleep, which is about 90-120 minutes each night.During the BDO-sleep, our body is paralyzed by a mechanism coming from our brains. It aims to protect us from making real movements caused by our sleep. It is possible that this mechanism is triggered before, during or after our normal while our brain actually wakes up.
source:econ.bg