Sleepwalking isn’t something you can decide to do on command. It’s an involuntary behavior that happens when your brain gets stuck between deep sleep and wakefulness, leaving your body mobile while your conscious mind stays offline. About 5% of children and 1.5% of adults experience it in any given year, and whether you sleepwalk largely comes down to genetics, sleep habits, and specific triggers rather than willpower or technique.
If you’re here because you want to understand what causes sleepwalking, what makes some people prone to it, or what’s actually happening in the brain during an episode, here’s what science knows.
What Happens in the Brain During Sleepwalking
Sleepwalking occurs during the deepest stage of non-REM sleep, typically in the first third of the night. During this phase, your brain produces large, slow electrical waves called delta waves. In people who sleepwalk, these delta waves show unusual patterns of instability. Instead of maintaining steady deep sleep, the brain flickers between states, producing incomplete arousals where some regions wake up (enough to move your body and navigate a room) while others stay deeply asleep (so you have no awareness or memory of what you’re doing).
Sleep researchers have found that sleepwalkers show this instability even on nights when they don’t sleepwalk. Compared to people who never sleepwalk, their deep sleep in the first two sleep cycles of the night has measurably less delta wave power. This means sleepwalking isn’t just a random event. It reflects a fundamentally different pattern of deep sleep architecture in people who are prone to it.
Why Some People Sleepwalk and Others Don’t
Genetics play the biggest role. If one or both of your parents sleepwalked, your chances go up significantly. Researchers have identified a specific immune-system gene variant, HLA DQB1*05:01, that appears in about 35 to 41% of sleepwalkers compared to only 13 to 24% of the general population. A separate study traced sleepwalking susceptibility in one family to a region on chromosome 20. The trait runs in families so reliably that a child with two sleepwalking parents has a notably higher risk than the general population.
Children sleepwalk far more often than adults because their brains spend more time in deep sleep and their arousal systems are still maturing. Most children who sleepwalk grow out of it by adolescence as their sleep architecture changes. When sleepwalking persists into adulthood or starts for the first time in an adult, it often signals that something is disrupting normal sleep patterns.
Triggers That Provoke Episodes
Even if you carry the genetic predisposition, sleepwalking usually needs a trigger to set off an episode. The most reliable one is sleep deprivation. When you haven’t slept enough, your brain compensates by diving into deeper sleep than usual, which increases the chance of those unstable partial arousals. This is why people often sleepwalk after pulling late nights or during periods of inconsistent sleep schedules.
Other known triggers include:
- Fever or illness: Being sick, especially with a fever, disrupts normal sleep cycling and can provoke episodes in people who are predisposed.
- Stress and anxiety: Emotional stress fragments sleep and increases the number of brief arousals during the night.
- A full bladder: The physical sensation of needing to urinate can partially wake the brain, just enough to trigger walking but not full consciousness.
- Environmental noise: Sounds that partially rouse you from deep sleep without fully waking you can set off an episode.
- Certain medications: The FDA has placed its strongest warning label on three prescription sleep medications (zolpidem, eszopiclone, and zaleplon) because they carry a notable risk of causing sleepwalking and other complex sleep behaviors, even in people with no history of it.
- Thyroid conditions: An overactive thyroid can occasionally cause sleepwalking, though this is uncommon.
What a Sleepwalking Episode Looks and Feels Like
During an episode, a sleepwalker typically sits up in bed and rises to walk with a blank, glassy-eyed expression. They’re difficult to wake and largely unresponsive to people trying to talk to them or redirect them. Episodes can be as simple as sitting up and looking around or as complex as walking through the house, opening doors, or even attempting to leave. Some people talk incoherently. Others perform routine actions like getting dressed.
The sleepwalker has little or no dream imagery during the episode, which is one of the ways it differs from acting out a dream (that’s a separate condition tied to REM sleep). Afterward, they typically have complete or near-complete amnesia for the event. If woken during the episode, they’ll often appear confused and disoriented for several minutes.
Why Sleepwalking Is a Safety Concern
Because sleepwalkers navigate the physical world without conscious judgment, injury is a real risk. They can fall down stairs, walk into furniture, attempt to leave the house, or interact with sharp or breakable objects. The lack of awareness means they can’t assess danger or respond to pain normally during an episode. This is the primary reason sleepwalking is treated as a medical issue rather than a curiosity, particularly when episodes are frequent.
How Sleepwalking Episodes Are Reduced
No medication is specifically approved for treating sleepwalking, and no large clinical trials have tested treatments head to head. The approaches that show the most benefit with the fewest downsides are behavioral rather than pharmaceutical.
The most effective technique is called scheduled waking. You (or a parent or partner) track the time sleepwalking episodes typically occur over several nights, then set an alarm for 15 to 30 minutes before that time. Gently waking the sleepwalker fully, keeping them awake for a few minutes, and then letting them fall back asleep interrupts the deep sleep cycle before the partial arousal can happen. This needs to be done every night for two to three weeks to reset the pattern.
Hypnosis has also been used with some success. In this approach, a clinician plants the suggestion that the sleepwalker will wake up fully the moment their feet touch the floor. The idea is to train the brain to complete the arousal rather than getting stuck in that half-awake state.
Beyond those strategies, reducing triggers makes a meaningful difference. Keeping a consistent sleep schedule, getting enough sleep, managing stress, and avoiding alcohol before bed all lower episode frequency. For safety, bedrooms should be on the ground floor when possible, windows and exterior doors should be locked, and breakable objects should be moved out of the path between the bed and the door.
If Someone Near You Is Sleepwalking
The best response is to gently guide them back to bed without startling them. Shaking, shouting, or slapping a sleepwalker is not helpful and can cause confusion or distress. Children in particular should simply be steered back to bed calmly. If the person is in immediate danger, like standing near a staircase, you can wake them, but expect several minutes of disorientation afterward.