Blue Sky Science: What’s going on in the brain when people sleepwalk?

Molly Torinus


What’s going on in the brain when people sleepwalk?

When we sleep we go through different types of sleep stages. You have slow-wave sleep, which is like your deep sleep, and then there’s dream sleep, which is called REM sleep.

We go through sleep cycles at night and alternate deep sleep and REM sleep. Sleepwalking tends to happen in your deep sleep or slow-wave sleep, usually in the first third of your night.

So what’s happening in your brain, to get to that question, is you’re actually in sleep when you’re sleep walking, and specifically in deep sleep or slow wave sleep. This is why people don’t remember what they’re doing when they’ve walked in their sleep.

There’s a continuum when it comes to sleepwalking or sleep actions. You can be just thrashing around and half awake in your bed, you could be sitting up frightened and screaming, or you could be getting out of bed and walking. They’re all non-REM, or non rapid eye movement, parasomnias.

Sleep terrors or night terrors happen often in younger children, and sleepwalking tends to happen in older children. But it’s the same thing happening in the brain.

Sleepwalking tends to happen in families, so if your parents or close relatives walk in their sleep you’re more likely to. Though it’s not a guarantee that you will.

There’s this idea out there that if you wake a sleepwalker, it’s dangerous. It’s probably not dangerous to them, but they are sleeping and don’t know what’s going on. It can be frightening or difficult for them to go back to sleep if they’re fully woken up.

What’s most important is to keep them safe. You can help by leading them back to their room, so they’re not walking outside or doing something dangerous, but also not trying to fully wake them up.