Why Do People Sleepwalk?

Watching a person sleepwalk must be one of the most eerie events you could ever experience.  Until I witnessed it myself, I thought sleepwalking was just something that happened on Saturday morning cartoons.  My perception of the phenomenon was changed forever when I was just a kid, and I was woken up in the middle of the night by the sound of our doorbell ringing. I cautiously opened my bedroom door and peered down both ends of our hallway, scared that it could be someone dangerous. My mom and dad followed soon after, wondering what on earth I was up to.  "Nothing," I remember saying. "I think someone's at the door."  We crept together in alarm toward the front door, and then we suddenly heard a loud knock-- which really scared me half to death.  Angered, my dad quickly swung open the door... only to find my kid sister standing there in her pajamas. "ASHLEY! What are you doing??" came my father's booming voice.  My poor sister just stood there, looking terribly confused.  "I don't know, I don't know," she insisted, and started to cry.  Shocked to find his baby girl outside so late at night, my Dad really started to get upset, until my mom finally suggested that Ashley had perhaps been sleepwalking.  Apparently, my little sister had wandered outside while she was asleep, and had ended up locking herself out of the house.  She finally woke up only because it was so cold!

This story presents an accurate description of what usually happens when a sleep walker is awakened, as feelings of disorientation and utter confusion are typical after-effects from this sort of incidents.  But what happens during the rest of the process? What could make certain people suddenly arise and take a midnight stroll-- all while fast asleep?  Researchers everywhere are fascinated by this question, and are at last beginning to make some headway in the research of the underlying causes.

Sleepwalking is a particular disorder that occurs when the normal physiological functions of the body are active at what would normally be considered "inappropriate" times1. In fact, people who sleep walk have been found performing an intriguingly wide range of activities, from simply raising upright in bed to attempting to cook a complete meal in the kitchen.  The unusual occurrence originates during the sleep cycle period known as Non-Rapid Eye Movement, or NREM.  This is the deepest portion of sleep that people experience every night, and is the period that proceeds dreaming.  Because NREM activity occurs more frequently early in life, children are often much more susceptible to sleepwalking events.  Though the reason this is true is still unknown, one thing that's quite clear is that the condition is genetically passed along from one generation to the next.

Although the mysteries behind sleepwalking are as yet unsolved, there are some interesting theories that are worth talking about.  Some research, for example, suggests that fatigue contributes to the level of frequency at which sleepwalking occurs.  Other researchers have suggested that particular chemicals are released during NREM which tell your brain to perform normal daytime functions.  In a recent study at the University of Montreal, 40 participants were chosen to be observed during two periods of sleep. The first period was referred to as "baseline" sleep which consisted of a normal, healthy night's rest.  The next period, however, was observed after those in the study were kept awake and monitored for 25 hours.  Out of said 40 participants, fully 32 showed such signs of abnormal activity from playing with the bed sheets to actually attempting to jump over the rails of the bed.  If you're someone, therefore, who is known to sleepwalk, do make sure you are getting plenty of rest, and this may go a long way to alleviate the condition.

Oftentimes, this "mixed state" of being exists when someone is simply aroused during their sleep mode.  And, to contribute to the idea that fatigue leads to sleepwalking, those that suffer from sleep deprivation disorders [such as insomnia and sleep apnea] are also known to sleepwalk.  A few simple solutions that are worth a try should you find yourself or someone you love having difficulty keeping from nighttime wanderings include getting to bed earlier, watching what you consume in the evening, and avoiding disturbances that could arouse consciousness during the restful state.

Finally, be aware that the conventional wisdom suggesting that awakening a sleepwalker has permanent effects which can be harmful to one's well being is only a myth.  The worst it could do, in fact, is embarrass the one who's doing it... and waking them up may help save you from disturbing late-night doorbell rings.