Which term describes REM sleep, highlighting the paradox of an active brain with a paralyzed body?

• A. Paradoxical sleep
• B. Narcolepsy
• C. NREM sleep
• D. Jet lag

Answer: (A)

REM sleep embodies a striking contrast: the brain is highly active, similar to wakefulness, while the body is effectively paralyzed to prevent acting out dreams. This paradox is captured by the term paradoxical sleep, highlighting the coexistence of wakeful brain activity with muscle atonia. The other terms don’t fit: narcolepsy is a disorder involving sudden sleep attacks and REM intrusion, not the name of the sleep stage; NREM sleep is the non-REM stage with lower brain activity and no dream-driven paralysis; jet lag describes circadian disruption from travel, not a sleep stage.