At what stage of the sleep cycle does somnambulism (sleepwalking) most commonly occur?

• A. During non-REM stage 3 (deep sleep)
• B. During non-REM stage 1 (light sleep)
• C. During REM sleep
• D. During the transition from wakefulness to sleep

Answer: (A)

Verified step by step guidance

1. Understand the different stages of the sleep cycle: Non-REM stage 1 (light sleep), Non-REM stage 3 (deep sleep), REM sleep, and the transition from wakefulness to sleep.
2. Recognize that somnambulism, or sleepwalking, is a parasomnia, which typically occurs during deep sleep rather than lighter sleep stages or REM sleep.
3. Recall that Non-REM stage 3 is also known as slow-wave sleep or deep sleep, characterized by slow brain waves and minimal muscle activity.
4. Note that parasomnias like sleepwalking are most common during Non-REM stage 3 because the brain is in a deep, restorative state but motor pathways can still be active.
5. Conclude that somnambulism most commonly occurs during Non-REM stage 3 (deep sleep).