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How Sleepwalking Works

Other Parasomnias
Sleep-eating is one side effect of Ambien.
Sleep-eating is one side effect of Ambien.
© Blasius Erlinger/Getty Images

Sleepwalking isn't the only parasomnia. There's also sleepsex, sometimes called sexsomnia or SBS (somnambulistic sexual behavior). It's pretty much what it sounds like -- sexual behavior during sleep. People with this condition might touch themselves sexually or initiate sex while asleep. They only know it happened when their roommate or partner mentions the incident. One man was actually acquitted of rape after using the defense that he was asleep at the time of the assault [source: The Independent]. People with sexsomnia tend to be sleepwalkers or have other parasomnias.

Just as disconcerting? Sleep-eating. You might associate sleep eating with the sleep aid Ambien. As the drug grew in popularity, stories began to crop up about people eating in their sleep. And not just getting up for a sandwich -- eating from tubs of margarine or eating cigarettes and raw meat. People wake up with crumbs in the bed or start putting on the pounds and have no idea why. They might come into the kitchen only to find tortilla chips all over the counters and cheese on the floor -- sloppy preparation seems to be a hallmark of sleep-eating. Ambien outsells all other RX sleep aids in its class, despite the possible strange side effects [source: NY Times]. Some people report that the problem stops after they switch to another drug, and that Ambien itself is the problem. Some doctors say that sleep-eating might just be another symptom of whatever's causing your sleepwalking in the first place.

Some people clench or grind their teeth while they sleep, a condition called bruxism. The grinding noise can be loud enough to wake up your sleeping partner -- some people say it sounds like the person is chewing rocks. It can damage the teeth, give you headaches and make your jaw hurt. If you're awake and grinding your teeth, you'll notice when it starts to hurt and you'll stop, but when you're asleep, the body isn't as attuned. One doctor claims that sleep bruxism results in 250 lbs. of pressure on the tooth [source: NY Times]. Stress makes bruxism worse, and some doctors recomment anti-anxiety medications for strong cases, although a special mouthguard should help.

Sleep bruxism could result in 250 lbs. of pressure on the tooth.
Sleep bruxism could result in 250 lbs. of pressure on the tooth.
Holloway/Getty Images

Sleep talking, sometimes called somniloquy, might wake up the person next to you, but it's harmless. Someone who sleep talks might just make noises, or could have a long one-sided conversation with you. Sleep enuresis is a fancy term for bed-wetting. REM sleep behavior disorder (RBD) is a bit like sleepwalking, only someone with RBD is acting out during REM sleep, the stage where your muscles shouldn't be moving at all. RBD usually results in people acting out their dreams, like the false perception people have of sleepwalking.

For more information on sleep and sleep disorders, there are links on the next page that might interest you.