Non-rapid eye movement (NREM) parasomnias involve disordered sleep-related behaviors that occur during the first few hours of sleep. Common treatment options typically include medication and psychotherapy.

Sleep is an essential part of our overall wellness, yet tens of millions of people in the United States alone live with conditions that make it difficult to sleep well. Between sleep apnea, insomnia, and other related disorders, sleep doesn’t always come easy to everyone.

Parasomnias are a group of sleep-related disorders that cause disruptive or unusual behaviors during sleep, as you’re falling asleep or waking up. Some parasomnias occur during the non-rapid eye movement phase of your sleep cycle.

Below, we’ll share everything you need to know about NREM parasomnias, including symptoms, causes, diagnosis, treatment, and more.

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NREM parasomnias describe disordered behaviors that happen when someone is in NREM sleep. Non-rapid eye movement (NREM) sleep is the first stage of sleep, and it includes three stages that span light and deep sleep.

Sleepwalking and sleep terrors are among the most common behaviors, although there are several different types of NREM parasomnias:

  • Sleepwalking: These episodes are characterized by routine activities, such as sitting up or walking, while asleep. Sleepwalking usually happens during stage 3 of NREM sleep, often within the first few hours of falling asleep.
  • Sleep terrors: Also known as night terrors, this condition is characterized by episodes of intense fear and terror during sleep. Sleep terrors also happen within the first few hours of sleep and are much more common in children than adults.
  • Confusional arousals: These are episodes of wakefulness characterized by disorientation, confusion, and other memory-related symptoms. Confusional arousals can happen immediately after waking up from NREM sleep.
  • Sexsomnia: Also known as sleep sex, this condition is characterized by sexual behaviors and activities during sleep. People with sexsomnia aren’t consciously aware of these behaviors and have no recollection of them after they wake up.
  • Sleep-related eating disorder (SRED): This condition is characterized by episodes of unusual eating and drinking behaviors that happen while asleep. Similar to sexsomnia, people with SRED have no awareness or recollection of their behavior.

Parasomnias are one of the most common sleep-related disorders, affecting an estimated 4% to 67% of adults. Sleepwalking is the most common NREM parasomnia, followed by confusional arousals and night terrors.

While researchers still aren’t entirely sure of what causes parasomnias, we know that NREM parasomnias typically occur during stage 3 or 4 of NREM sleep. Because of this, disruptions during these stages of sleep appear to play the largest role in causing these behaviors.

Some of the most common disruptions that can happen during NREM sleep include:

Because researchers aren’t certain of what exactly causes NREM parasomnias, it can be difficult to narrow down the exact risk factors for these conditions.

However, some of the possible underlying factors that may increase the risk of someone experiencing NREM parasomnias include:

  • family history
  • lack of sleep
  • natural body movements
  • loud noises or physical touch
  • restless leg syndrome
  • sleep-related breathing disorders
  • alcohol use
  • increased stress
  • fever and illnesses

If you believe you’ve been experiencing NREM parasomnias, a doctor will start by reviewing your medical history and performing a thorough physical exam.

Doctors can diagnose NREM parasomnias using criteria from two sources:

  • the International Classification of Sleep Disorders, Third Edition (ICSD-3)
  • the Diagnostic and Statistical Manual for Mental Disorders, Fifth Edition (DSM-5)

To be diagnosed with NREM parasomnia, your symptoms will need to match the following:

You regularly experience:

  • incomplete awakening from sleep
  • a lack of response to efforts of others to intervene or redirect you during the episode
  • limited or no associated dream imagery
  • partial or complete amnesia about the episodes

Your symptoms should also:

  • occur during the first third of the major sleep episode
  • cause you to feel confused or disoriented for several minutes or longer after the episode
  • not be better explained by another health condition, such as another sleep disorder

After a thorough review of your symptoms and medical history, a doctor may also refer you to a sleep specialist for more testing. Polysomnography (PSG) and other tools like home video recordings can be helpful for diagnosing parasomnias.

Generally, the treatment for NREM parasomnias involves a combination of multiple approaches, including medication, therapy, and lifestyle measures.


People who experience frequent or more severe parasomnia episodes might benefit from medication to help reduce their recurrence.

Some of the medications that may be helpful for managing parasomnias include:

As research on the effectiveness of these medications for NREM parasomnia is limited, it may take some time to find the medications that work for you.


Cognitive behavioral therapy (CBT) is a type of psychotherapy that has been shown to decrease the symptoms of mental health conditions like depression and anxiety.

Research suggests that certain CBT approaches may help manage NREM parasomnias by addressing underlying mental health risk factors.

Lifestyle measures

Other lifestyle measures that may help manage NREM parasomnias include:

  • improving sleep hygiene
  • creating a safe sleep environment
  • addressing other underlying health conditions, such as:
    • sleep apnea
    • anxiety
    • depression
    • post-traumatic stress disorder (PTSD)
    • Parkinson’s disease

What is the main cause of parasomnia?

The main cause of parasomnia is typically mental health conditions such as anxiety, depression, and PTSD.

Is parasomnia dangerous?

While parasomnia itself is not dangerous, it can increase the risk of you injuring yourself or others.

What are examples of parasomnias?

Common examples of parasomnias include sleepwalking, night terrors, and sleep paralysis.

NREM parasomnias encompass several different disordered sleep behaviors that occur during NREM sleep — typically during the first half of the night. Sleepwalking and night terrors are two of the most common types of NREM parasomnias, especially in children.

NREM parasomnias can have a significant effect on not only someone’s sleep quality but also their day-to-day life. However, with the right treatment, people who experience these parasomnias can learn how to manage symptoms in the long run.