University of Minnesota
June 12, 2012
U neurology professor Mark Mahowald has found that about 29 percent of people have been sleepwalkers at some point in their lives.
Sleepwalking is more prevalent—and less problematic—than originally thought
By Rick Moore
Of all the behaviors associated with sleep, sleepwalking is likely the most mysterious. After all, everybody can relate to stories of bizarre dreams. But how do we account for people being half awake and half asleep at the same time?
As it turns out, sleepwalking is far more prevalent—and “normal”—than we might have imagined, according to research by U neurology professor Mark Mahowald. In a recent study published in the journal Neurology, Mahowald found that 3.6 percent of adults have sleepwalked in the past year, and about 29 percent of people have been sleepwalkers at some point in their lives. More than 19,000 adults were surveyed in the first extensive study to quantify somnambulant behavior.
“The take-home is that sleepwalking is very, very common, and when you understand sleepwalking you understand a bit more about how the brain works,” says Mahowald.
A normal part of the human condition
In essence, when people are sleepwalking, different parts of their brain are simultaneously awake and asleep, says Mahowald, former director of the Minnesota Regional Sleep Disorders Center and a visiting professor at Stanford University, which hosted the study.
The part of the brain responsible for very complex motor behaviors is awake, which accounts for the actual walking and other physical activities. Meanwhile, the part that’s asleep is responsible for monitoring what we’re doing, as well as recording the affiliated memories.
Indeed, it’s possible to unintentionally elicit sleepwalking, which many parents do when they wake their sleeping youngsters to transfer them to bed. “It can be induced in normal individuals under appropriate circumstances,” Mahowald says.
Speaking of normal, sleepwalking is essentially just that, despite the misconceptions that society still holds.
One is that sleepwalking is acting out dreams. In reality, sleepwalking “does not come from dream sleep; it comes from non-dream sleep,” says Mahowald.
Another misconception is that sleepwalking is the manifestation of repressed aggression or hostility, or worse yet, that when exhibited in adulthood it’s a sign of mental illness.
“It really doesn’t correlate with any serious psychiatric disease,” he says.
About last night
Still, sleepwalking has likely gone underreported over the years. Adults tend not to want to be labeled as sleepwalkers, and they’re not always forthcoming about all of their nighttime behaviors.
For instance, people have shared with Mahowald their stories of getting up in the middle of the night, presumably with a full bladder, and relieving themselves in non-porcelain receptacles, like a shoe or a wastebasket.
“If you’re at a cocktail party, you don’t say, ‘Look what I did last night,’” Mahowald quips. “That’s not polite party conversation.”
At the very least, sleepwalkers should take solace in knowing that they’re definitely not alone, even if they choose not to share all their stories.
“[Sleepwalking is] just incredibly common,” Mahowald says, “but nobody talks about it.”