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NREM Parasomnias

Parasomnias are sleep disorders. They are abnormal movements that a person experiences while he sleeps. A person can also experience these in between sleep stages. Some experience them during arousal and they may involve abnormal behaviors and emotions. There are even some parasomnias that result in abnormal perceptions or dreams.

REM sleep behavior disorder and sleep paralysis are examples of parasomnia. Both of these happen while a person is in the Rapid Eye Movement Sleep stage. Some parasomnias, however, occur when a person is in the Non-REM (NREM) sleep stage. There are more NREM sleep parasomnias compared to REM sleep parasomnias. This is not surprising because a person spends more time in NREM sleep compared to REM sleep.

An NREM parasomnia is something that a person can experience while the brain is partly in Non-REM sleep and partly awake. This means that the brain is awake enough to perform complex activities. A person is not consciously aware though of what he or she is doing. An NREM parasomnia occurs during Slow Wave Sleep (SWS). NREM Parasomnias often doesn’t have any underlying medical conditions. This means that they are not the result of another disease. They are also treatable most of the time.

What are the types of NREM Parasomnias?

Confusional Arousals

During an episode of confusional arousal a person acts in a strange or confusing way. Confusional arousals happen when a person is waking up. An episode can also happen right after a person wakes up. During an episode the patient is often unaware of where he is. The patient is also unaware of what he is doing. This is why patients often describe it as being in a foggy state of mind. Everything seems to be unclear or blurred. It is also common for a patient to sleepwalk during an episode. Some shout during an episode. Some patients even grind their teeth. These episodes generally last for a few minutes. Some episodes, though, last several hours.


Sleepwalking’s formal name is somnambulism. This is a disorder that originates from a deep sleep. Just like what its name suggests, a person walks while sleeping as a result of an episode. Some patients even perform complex activities even though they are asleep. An episode starts during deep sleep. The symptoms of this disorder, however, present themselves when a person is in the lighter stages of sleep.

The symptoms of sleepwalking are not limited to walking. Some symptoms are simple. A person may just end up sitting up in bed. Others are quite complex. Some patients may end up walking around the room or the house. It is even possible for some patients to leave the house and end up driving long distances. This is why sleepwalking is a very dangerous disorder. It can lead to injuries or even fatal accidents.

Sleep Terrors

A sleep terror or a night terror is a parasomnia similar to a nightmare. This is a disorder that causes fear in a sleeping person. Although it is common among children, it can also affect adults. This is something that’s distressing not just to the patient but also those around the patient.

A common sign of sleep terror is the flailing of the patient’s limbs. Some patients emit frightened screams during an episode.  A typical episode of sleep terror lasts between 30 seconds to 3 minutes. Some episodes can last longer.

Sleep Sex

Sleep sex is a parasomnia where a person engages in sexual acts while asleep. It is a relatively new parasomnia. The first official case got reported in 1986. Sexsomnia is another name for sleep sex. It is different from sexual dreams in the sense that dreams do not involve any physical actions. The most that can happen with sexual dreams is that a person ejaculates. It is very difficult to study sleep sex because the episodes occur randomly.

During an episode of sleep sex a patient usually touches himself or herself sexually. An episode can also involve sexual motions. It can also cause a person to unknowingly seek sexual intimacy. Sleep sex often occurs at the same time as other parasomnias like sleepwalking.

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