In what sleep stage does somnambulism typically occur?

Somnambulism, commonly referred to as sleepwalking, typically occurs during the N3 stage of sleep, which is also known as slow-wave sleep (SWS) or deep sleep. This stage is characterized by the presence of delta waves on an EEG and is crucial for restorative processes in the body. During N3, the brain is less responsive to external stimuli, making it an ideal time for the body to engage in complex motor activities, such as walking, without the individual being conscious of their actions.

Sleepwalking is not typically seen during lighter sleep stages (N1 and N2) or during REM sleep when the body experiences muscle atonia (temporary paralysis) to prevent acting out dreams. Thus, the unique characteristics of N3, particularly its depth and the level of consciousness, explain why somnambulism most frequently occurs during this stage.