Why Does Rem Sleep Occur? A Wake-Up Hypothesis
Frontiers in Systems Neuroscience June 1, 2011 W. Klemm
The brain may use rapid eye movement (REM) sleep to help wake itself up after sufficient sleep. Evidence includes that REM episodes become longer and more frequent toward morning, conscious-like dreams occur reliably in REM, the final awakening of the night usually happens during a REM episode, and both REM and wakeful consciousness arise from a similar brainstem arousal system. The hypothesis explains common experiences and aligns with findings on sleep ontogeny, aging, phylogeny, disease, cognition, and behavior. Competing theories do not match this breadth of consistency. Specific tests are proposed to further investigate this wake-up hypothesis.