Somnambulism is the medical term for sleepwalking. People experiencing somnambulism get up and walk around while they're still asleep, with no memory of doing it when they wake up.

A person who sleepwalks is called a somnambulist.

Somnambulism happens during deep sleep, when part of the brain wakes up enough to control movement but not enough to be conscious or form memories. A sleepwalker might sit up in bed, walk to the kitchen, or even go outside, all while genuinely asleep. Their eyes might be open, but they're not really seeing or thinking clearly.

Somnambulism is most common in children and usually stops as they get older. Scientists still don't completely understand why it happens, though stress, exhaustion, and irregular sleep schedules can make it more likely. While sleepwalking might seem mysterious or even funny in movies, real somnambulism can be dangerous because the person isn't aware of obstacles or hazards around them.