Inside the fascinating world of sleepwalking

Rearranging furniture, making meals, wandering the streets – sleepwalking is a fascinating and potentially dangerous disorder. But what causes it?

Most of us welcome the blissful state of slumber (some of us spend large parts of the daydreaming about it).

But for Perth TV producer and podcaster Doug MacLaurin, night time when he was younger could be fraught.

“I was a sleepwalker, and I did a fair bit of it,” Doug says.

“One time I wandered out to the garden, right through a party my parents were having and filled a bucket up with water.

“I had absolutely no recollection the next day of doing it.”

How common is sleepwalking?

Doug is far from alone. In 2016, UK singer songwriter Robbie Williams wrote on social media that his sleepwalking episodes saw him raiding his fridge and cupboards for food.

So, just how many of us are nocturnal wanderers?

Research has found 6.9 per cent of us sleepwalk at some point in our lives, with child sleepwalkers outnumbering adults.

Clinical psychologist and somnambulism (sleepwalking) expert Dr Helen Stallman, who authored a 2017 review of the latest science on sleepwalking.

She says the condition is often misunderstood and under-recorded.

“We don’t know exactly how many people sleep walk because most people have no memory of doing it,” Dr Stallman says.

“It’s probably why more married people reportedly sleepwalk than single people, because there’s someone who notices.”

What causes sleepwalking?

Sleep expert from The University of Western Australia Dr Ian Dunican says sleepwalking belongs to a category of sleep disorders known as the “parasomnias”, that also include night terrors.

“It occurs during the deepest stage of sleep, the stage known as non-REM sleep,” Dr Dunican says.

He says adults have less non-REM or slow wave sleep as they get older, which may explain why numbers are lower than with kids, who tend to get more sleep.

“Sleepwalking often only lasts minutes and could involve just sitting up in bed, but it can go longer and involve more complex behaviours, such as walking around and even driving a car,” he says.

While the precise causes of sleepwalking are still being investigated by scientists, Dr Stallman says family history may play a part, along with certain medications.

“That’s the first thing we rule out in clinical practice when we’re looking at adults who sleepwalk – any medications they’re taking that may cause sleepwalking,” she says.

Is sleepwalking dangerous and how can I stop it?

It can be. A study published in 2013 followed 140 sleepwalkers in Montpellier in France, videoing them while they slept, concluding it was “a potentially serious condition”.

Dr Stallman says sleepwalking can result in injury, such as falling from a high point or walking through glass doors or windows.

But she says it has been associated with other sleep problems such as night terrors, sleep talking and teeth grinding.

“These sorts of sleep disorders, rather than sleepwalking itself, have been found to account for issues such as daytime tiredness and behavioural and emotional problems,” she says.

“We recommend locking windows and external doors and removing breakable objects, but not locking sleepwalkers in their bedrooms, which can be a fire risk.”

Dr Stallman says scheduled sleep-waking, which involves waking child sleepwalkers briefly 15 to 30 minutes before they would normally sleepwalk, and hypnosis for adult sleepwalkers, are treatments that may be successful in preventing sleepwalking.

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Written by Liz McGrath.