Odd Things People Do in Their Sleep

Sleepwalking is actually a type of sleep disorder called a parasomnia. Learn even more uncommon things people do while asleep, from eating to having sex.

Some sleep disorders are actually quite common. Most people talk in their sleep, and some are prone to sleepwalking.

But other parasomnias are more unusual, like sleep sex or sleep crime. “Parasomnia is abnormal behavior that occurs during sleep,” says David A. Neumeyer, MD, a sleep specialist at the Lahey Clinic in Burlington, Mass. “Some of these behaviors can be kind of weird and scary.” People acting out a parasomnia have no conscious control of their actions, which can be both disturbing and dangerous.

Sleep Sex

This sleep disorder is called sexsomnia. You may see occasional cases in the news, for example as a defense used by someone accused of rape. The argument is that they were asleep and don’t remember a thing. “It could be true, but it’s very hard to prove,” says Dr. Neumeyer. Sleep sex is very rare and, like other sleep disorder parasomnias, could be triggered by sleep deprivation, alcohol, antidepressant medications, or sleep aid medications.


If you have ever awoken from sleep to the terror of a mysterious stranger at the foot of your bed, you have probably experienced a hypnagogic hallucination. Sleep-related hallucinations can be vivid and realistic, sometimes making them a terrifying sleep disorder. They are usually visual, but they can also involve the false sensation of sound or touch. More than half of adults have likely experienced them at least once. Hallucinations and other sleep disorders may be more common in people who have sleep apnea or restless leg syndrome.

Waking Up Angry

Almost everyone has woken up on the wrong side of the bed, usually because of poor sleep habits. But people with confusional arousal disorder wake up frighteningly mean. This sleep disturbance can happen in children as well as adults (in fact it often runs in families), and it affects up to 4 percent of the population. People wake up in a state of total confusion and may become very agitated or aggressive. It’s more likely to happen if someone is forced awake during the early stages of sleep. The aggression tends to wear off after they fully awake, usually within 5 to 15 minutes. They will have no memory of their earlier behavior.

Sleep Eating

Nocturnal sleep-related eating disorder is a sleep disorder similar to sleepwalking. “People with this sleep disorder may get up at night, raid the fridge, and have no memory of eating the next morning,” Neumeyer says. “The only sign may be that the leftovers are gone.” This disorder has been known to cause unexplained weight gain in some cases. Sleep eating is rare, usually occurs in women, and may be triggered by antidepressants or sleep medications.

Sleep Driving

Like sleep sex and sleep eating, it’s possible to wake up, go for a spin, go back to bed, and not remember a thing. As you can imagine, sleep driving is very dangerous. The increased use of sleep aid medications may be increasing its prevalence. In fact, the U.S. Food and Drug Administration now requires a warning label on all sleep aid drugs about the potential of developing these types of sleep disorders.

Acting Out Your Dreams

Even if you’re dreaming about dancing with George Clooney, your body is likely staying put in bed. For some people, though, their bodies act out whatever they’re doing in their sleep. “The sleep disorder called REM sleep behavior disorder can cause someone to do just that,” says Neumeyer. “Normally when you are in the deep stage of dreaming sleep called REM sleep, only your eyes and your breathing muscles move. In this sleep disorder, those restrictions fail and you actually do your dream.”

More men are affected by this sleep disorder, usually after age 50.

Committing Crimes

It may sound like something out of a horror movie, but people with REM sleep disorder often have dreams that are action-packed and violent. “This has led to several cases in the medical literature where people have committed violent crimes and then claimed that they did it while they were asleep,” Neumeyer said. “Sleep studies can show that people do act out their dreams, but who knows if they were dreaming when they committed their crime.” REM sleep disorder occurs in less than 1 percent of the population. The disorder may be related to Parkinson’s disease, as about 40 percent of people with this sleep disorder go on to have Parkinson’s.

Night Terrors

Night terrors are uncommonly vivid nightmares, occurring in about 2 percent of adults. This type of nightmare can cause the dreamer to actually jump out of bed and try to escape through a door or window. Night terrors tend to run in families and, like other sleep disorders, may be triggered by poor sleep habits and medications. If better sleep habits don’t solve this problem, talk to your doctor. Acting on your dreams can cause some nightmares to become real dangers.

Chris Iliades, MD