Sleepwalking is a behaviour that involves a person getting up and walking around or performing other tasks while they are still in a state of sleep. People have been intrigued by the phenomenon of sleepwalking — also known as somnambulism — for hundreds of years. Writings from the 13th and early 14th centuries indicate that medieval theorists believed reason and sensation were disabled during sleep. They posited that this allowed the imagination to take control, resulting in episodes of sleepwalking. A common example of the time described an aristocrat who arose from bed, armed himself, and mounted his horse in his sleep, imagining he was fighting enemies or hunting.
The cultural fascination with sleepwalking persisted and in the 17th century, William Shakespeare’s tragedy Macbeth would feature a leading character, Lady Macbeth, sleepwalking as she recollected memories of her past in one of the play’s most famous scenes. In the 19th century, scientists began studying sleepwalking extensively — since then, research has uncovered interesting and surprising information about the behaviour and why it might occur.
Why do people sleepwalk?
Episodes of sleepwalking happen during the deepest stage of non-rapid eye movement sleep, often one to two hours after a person falls asleep. Sleepwalking is understood to be more prevalent in children than in adults — research from 2016 found that 5% of children are affected by somnambulism, with the figure dropping to 1.5% for adults. A 2015 study suggests that family history may play a role in sleepwalking: children were reported to be more likely to sleepwalk if one or both of their parents had experienced episodes of the behaviour.
Sleep disorders that can cause people to awaken frequently throughout the night — such as obstructive sleep apnea (OSA) — may also spur episodes of sleepwalking.
There are a number of factors believed to be potential triggers for sleepwalking, including:
- Stress and anxiety
- Not getting enough sleep
- Waking up suddenly from a deep sleep (due to a sudden noise, for example)
- Certain types of medication, including some sedatives and antidepressants
What are the symptoms of sleepwalking?
A person’s eyes are typically open when they are sleepwalking, often with a distant or glazed look. A sleepwalker won’t usually respond if someone tries to get their attention (by asking them if they are awake, for example). If they do, their responses may be incomplete or may not make sense.
If the sleepwalker is in a familiar environment, they may be able to navigate their surroundings with relative ease. Activities like getting dressed, preparing food, and talking are known to occur during episodes of sleepwalking — in extreme cases, a person may leave their home and perform a complex task, such as driving a car.
While sleepwalking, a person may be difficult to awaken. When they wake up afterwards, they may be confused for a short time. Most instances of sleepwalking last for less than 10 minutes, but episodes can range in length from a few seconds to half an hour. Often, the sleepwalker will have little or no memory of the episode the following morning.
Is it safe to wake someone who is sleepwalking?
Because a sleepwalking person is not aware of what they’re doing, a sudden awakening can lead to confusion, anger, or fear. Softly guiding a sleepwalker away from potential dangers and back to bed in a quiet voice can help ensure their safety without awakening them.
Injuries from trips, falls, or collisions with objects can occur when a person sleepwalks. In circumstances where it is necessary to wake a sleepwalker, the person intervening should be as gentle as possible and should be aware that the sleepwalker may be disoriented or upset when they awaken.
Treatments for sleepwalking
A number of approaches can be taken to address sleepwalking and ensure the sleepwalker’s safety if they do experience an episode. A person's sleep environment and habits (known as their sleep hygiene) can play a role in sleepwalking. Poor sleep hygiene — such as having an inconsistent sleep schedule — can exacerbate sleep problems and lead to sleep deprivation, which may increase the likelihood of sleepwalking episodes. Practising good sleep hygiene can enhance sleep quality and reduce the risk of sleepwalking episodes triggered by a lack of sleep.
Particularly for children who sleepwalk, a technique known as anticipatory awakening (or scheduled awakening) has been proven to be effective in preventing episodes. Anticipatory awakening involves waking a person up shortly before a potential sleepwalking episode is likely to happen. Sleepwalking is associated with a specific sleep stage, so it often occurs around the same time each night — waking someone up just before that time can prevent them from experiencing the partial awakening that is believed to trigger sleepwalking.
If a person's sleepwalking is linked to an underlying health condition like obstructive sleep apnea, treating that condition may also resolve problems with sleepwalking. In cases where sleepwalking is caused by medication, a doctor will be able to recommend treatment options (such as adjusting the dosage or switching to a different drug).
Occasional sleepwalking is not necessarily a cause for concern — in many sleepwalkers, episodes tend to become less frequent with age and the sleepwalker’s behaviour does not put them or others around them in harm’s way. Keeping sharp objects or weapons locked away, closing and latching doors and windows, and removing tripping hazards from the floor can lower the risk of injury to someone who is sleepwalking. However, It’s important to consult a doctor if chronic or severe episodes of sleepwalking are affecting a person’s day-to-day life or placing them in dangerous situations.