The Science Behind Sleepwalking
Neurology estimates that about 3.6 percent of Americans are prone to nocturnal wandering, a.k.a. sleepwalking. This equates to over 8.4 million people that have had a sleepwalking episode in the past year. While this number may surprise you, keep in mind that nearly 30 percent of respondents in the same study reported some form of sleepwalking at some time in their life. Also known as somnambulism, this is considered a disruptive sleep disorder.
When Do People Sleepwalk?
Sleepwalking occurs during NREM sleep – when we sleep the deepest. The sleep cycle ranges from the lightest stage of NREM to the heaviest, then back to the lightest stage of NREM, then to REM sleep. This cycle repeats several times a night. Sleepwalking usually occurs in the deepest NREM stage. Your muscles are paralyzed during REM sleep, which prevents wandering. Within REM, dreaming takes place. Some researchers think sleepwalking might occur when the body tries to go from deep NREM straight into wakefulness, without going through the entire sleep cycle. It can last for anywhere from 30 seconds to 30 minutes, and usually occurs during the first third of the night.
How to Recognize a Sleepwalker
Sleepwalkers have a glassy gaze and a blank expression on their face. They will display clumsy behavior, although they seem to be fully functional. People have been known to cook, wander the neighborhood, play instruments, drive, and even commit crimes while asleep. The fact that this phenomenon occurs in the deepest stages of sleep explains why waking a sleepwalker is more difficult. Controversy exists on if you should wake a sleepwalker or not. Some experts say to avoid it, while others state there is no danger. However, after waking a sleepwalker, they will seem disoriented and confused for a few minutes. Sleepwalkers have no memory of their activities during their nighttime wandering, as they are unconscious. Injuries from tripping or falling are common as motor skills are not at 100 percent.
Why Do People Sleepwalk?
Although multiple studies have been done on sleep and sleepwalking, scientists are still not entirely sure the exact science behind why we need sleep or why some people sleepwalk. Factors that seem to increase the chances of sleepwalking are the amount of time you stay in the deepest stages of NREM, sleep deprivation, fever, and stress. Furthermore, some medications prescribed for depression and sleeping disorders can increase the amount of time you deep sleep. Children tend to be more prone to nocturnal wandering than adults, and usually grow out of it.