Parasomnias: Things That Go Bump in the Night
A mother is awakened in the middle of the night by aterrifying scream. She races to the room of her 3-year-old son. He is sitting up in bed with tears running down his face, his heartpounding. The more she tries to soothe him, the more agitated hebecomes. A college student walks into her parents' bedroomwhile they are sleeping and pours a glass of water into her mother'sdresser drawer.What these two situations have in common is that, in the morning,they do not remember a thing.These stories—all true—are examples of parasomnias, which are defined as unpleasant or undesirable behavioral or experiential phenomena during sleep.
Defining ParasomniaAbnormal things that can happen to people while they are sleeping are called parasomnias. Examples of parasomnias include sleepwalking andnight terrors. While they can be frightening to observe, most parasomnias areharmless and require no treatment beyond some simple safety measuresto keep people from injuring themselves during an episode.Parasomnias are more common in children than in adults because the condition most often occurs during deep sleep, which decreases as we age.
The Difference Between REM and Non-REM DisordersParasomnias fall into 2 main categories—disorders of REM sleep and non-REM (NREM)sleep.REM, short for rapid eye movement, sleep is the most active stage of sleep during the second half of the night. This is when most dreams and nightmares occur. During REM sleep, our muscles become relaxed and immobile to keep us from acting out our dreams. In those with REM behavior disorder, the muscles do not relax and people act out their dreams as though awake. Some things that may occur during this time are hitting, punching, or yelling. This disorder can lead to injury of the dreamer or the bed partner. During this time, the dreamer is really asleep.For most of the night, we are in NREM sleep, which includes the deep sleep. This is when sleepwalking and night terrors occur.A major difference between the nightmares of REM sleep andthe night terrors of NREM sleep is that nightmares involve acomplex plot that may be recalled in detail, while the imagesinvolved with night terrors are primitive and simplistic, suchas fire, a monster, or the ceiling falling down that are not recalled.
SleepwalkingSleepwalking is more prevalent in children than adults. There are many reasons people sleepwalk, but one of them may be hereditary.During this time, the sleepwalker may be unresponsive and appear awake. Sometimes awakening the sleepwalker can trigger aggression and violent behavior. It is best not to wake the sleepwalker. Try to redirect the person back to bed if possible.
Night TerrorsNight terrors differ from nightmares. They occur during non-REM sleep, generally in the first third of the night. They may include incomplete arousal, confusion, unresponsiveness, and amnesia. They can occur in a small minority of children up to 8 years old. Night terrors may also be accompanied by sleepwalking.Keep in mind that night terrors may render a child inconsolable for several minutes. Once relaxed, the child will often fall back to sleep.
How Do You Treat Parasomnias?The good news is that most of these things eventually go away on their own. Some people however, need more involved treatment. This may include educating family members on how to respond to parasomnias, relaxation therapy, and, rarely, medication.
Prevention TipsYou can help prevent parasomnias by having your child keep the same sleep schedule and get enough sleep. This will prevent the increase in deep sleep that can trigger sleepwalking, night terrors, and other parasomnias.
Other Safety MeasuresThere are some general safety precautions you can take if you orsomeone you know experiences parasomnias:
- Lower the bed to the floor. It is harder to get up out of a mattress on the floor.
- Sleep in a sleeping bag. It is harder to get out of than typical blankets.
- If bedrooms are on the second floor, move the bed to the firstfloor.
- Latch windows and lock doors.
- Put gates across stairwells.
- Put bells or alarms on door knobs.
- If a person is staying in bed during a night terror, then no harm will occur. Do not try to restrain the person; it can result in agitation.
National Heart, Lung, and Blood Institute
National Sleep Foundation
Better Sleep Council Canada
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- Reviewer: Michael Woods, MD
- Review Date: 01/2015
- Update Date: 01/02/2015