Definition
Rapid Eye Movement — the sleep stage characterized by rapid eye movements. The majority of dreams occur during this phase. The brain is highly active while the body experiences temporary paralysis.
Related Terms
Sleep Cycle
A cycle of approximately 90 minutes consisting of NREM and REM stages, repeating 4-6 times per night. REM duration increases with each cycle, and dreams become more vivid.
Sleep Paralysis
A temporary condition where the body cannot move while consciousness is awake during sleep onset or awakening. May be accompanied by hallucinations and fear. Culturally associated with 'the nightmare' or incubus.
NREM Sleep
Non-REM sleep stages. Consists of three phases: light sleep, medium-depth sleep, and deep sleep. Dreams can occur in these stages but are typically less vivid and shorter.