A parasomnia is a sleep disorder that causes abnormal behavior while sleeping. The behavior can occur during any stage of sleep, including the transition from wakefulness to sleeping and vice versa.
If you have a parasomnia, you might move around, talk, or do unusual things during sleep. Other people might think you’re awake, but you’re actually unconscious. You typically don’t remember the incident.
While parasomnias are common, they can make it difficult to get restful sleep. The behavior might also disrupt the sleep of other people near you.
Additionally, some parasomnias can be dangerous because you’re unaware of your surroundings. They can also have health-related side effects, such as psychological stress.
Like other sleep disorders, parasomnias are treatable. Read on to learn about the causes and types of parasomnias along with treatment options.
Types of Parasomnia
While each parasomnia carries distinct symptoms and diagnostic criteria, these behaviors can be categorized into three general groups3: NREM-related, REM-related, and “other.”
Non-rapid eye movement sleep constitutes the first stage of one’s sleep cycle, known as “shallow” sleep, and the second, third, and fourth stages, during which the sleep becomes gradually deeper. Collectively, these stages usually last about 90 minutes.
The most common NREM-related parasomnias are known as disorders of arousal. These parasomnias are characterized by recurrent episodes of incomplete awakening, limited responsiveness to other people attempting to intervene or redirect the sleeper, and limited cognition during the episode. Most people who experience disorders of arousal have little to no memory of their episodes. These disorders include:
- Confusional arousals: The sleeper exhibits mental confusion or confused behavior in bed. Most people who experience confusional arousals display very little autonomic arousal in the form of mydriasis (dilated pupils), tachycardia (accelerated heartbeat), tachypnea (accelerated breathing), or perspiration. Confusional arousals are also known as Elpenor syndrome.
- Sleepwalking: Also known as somnambulism, sleepwalking occurs when people get out of bed while still asleep but exhibit limited awareness or responsiveness to their surroundings. They may exhibit other complex behaviors such as sorting clothes. Sleepwalking can also lead to injuries if the individual loses their balance or collides with other objects.
- Night terrors (or sleep terrors): People who experience night terrors often scream in their sleep, though most are not responsive to outside stimuli and will have no recollection of the source for their terror upon waking. Most night terror episodes last between 30 seconds and three minutes.
- Sleep-related sexual abnormal behaviors: Known colloquially as “sexsomnia,” this specific parasomnia subtype is characterized by unusual sexual behaviors during sleep, such as aggressive masturbation, initiation of sexual intercourse, and sexual noises.
Studies have shown that males and females are equally susceptible to disorders of arousal, though age appears to play a role. Parasomnias have been reported in roughly 17% of children ages three to 13. For children and adults 15 and older, the prevalence rate falls between 2.9% and 4.2%.
Another common NREM-related parasomnia is sleep related eating disorder, which is characterized by episodes of dysfunctional eating that occur after arousal from sleep. Most people with this condition exhibit limited responsiveness during their eating episodes, and have little to no memory of the events. Hazards associated with sleep related eating disorder include ingestion of toxic substances, injuries from cooking or preparing food, and physiological effects of unhealthy or excessive eating.
Rapid eye movement sleep occurs following the first four NREM stages of the sleep cycle. Following the first complete sleep cycle, NREM and REM stages will repeat in a cyclical fashion every 90 minutes or so for the rest of the night. As the name suggests, a person’s eyes will move rapidly beneath their eyelids during REM sleep4. They will also experience faster breathing, and increases in both their heart rate and blood pressure.
Common REM-related parasomnias include:
- REM sleep behavior disorder: This disorder – RSBD for short – is characterized by unusual vocalizations or movements during REM sleep, often as a reaction to a dream. It is usually attributed to dysfunction in the muscles responsible for skeletal muscle atonia, the extremely relaxed state that occurs in the REM stage. People with RSBD may undergo polysomnography examinations that record brain activity during the REM stage. This condition is most common in people aged 50 or older. Clinical findings of RSBD may be noted in patients taking certain anti-depression medications5.
- Recurrent isolated sleep paralysis: People with this condition feel complete bodily atrophy during sleep onset – the period before they fall asleep – or upon waking. They will not be able to move any part of the body during these episodes, which normally don’t last more than a few minutes. Sleep paralysis can lead to anxiety or distress about falling asleep.
- Nightmare disorder:Everyone has unpleasant dreams every now and then. Nightmare disorder is limited to those who experience recurrent, vivid dreams defined by threats to survival or security that result in fatigue, distress, reduced cognition, and other daytime impairments. Nightmare disorder is a common component of Post-Traumatic Stress Disorder (PTSD). Motor activity is often limited during nightmare episodes. For children with nightmare disorder, severe psychosocial stressors are often to blame.
The “other” category for parasomnias is dedicated to behaviors that occur during the transition between sleep or wakefulness, as well as those that can occur during NREM or REM sleep. These parasomnias include:
- Exploding head syndrome: Also known as sensory sleep starts, people with this condition will hear a loud noise or feel an exploding sensation in their head when they wake up. They may also “see” an imagined flash of light upon waking. This sensation can leave the sleeper with lingering feelings of palpitation, dread, and anxiety, but it is usually painless. Some people may experience multiple episodes per night.
- Sleep related hallucinations: People with this condition experience hallucinations either during sleep onset (hypnagogic) or when they wake up (hypnopompic). These hallucinations may be visual, auditory, tactile, or kinetic in nature. In extreme cases, sleepers may leave their bed in an attempt to escape what they are experiencing. The hallucinations may persist for up to several minutes after the sleeper awakens.
- Sleep Enuresis: Known throughout the world as “bedwetting,” sleep enuresis refers to involuntary urination during sleep. Bedwetting is quite common in young children. To be considered a parasomnia, it must occur in people ages five and older and occur at least twice per week for at least three months. Primary sleep enuresis refers to people who never wake up feeling dry, while secondary sleep enuresis occurs in individuals who have not previously experienced bedwetting episodes for at least six months before the first episode occurs.
This list of parasomnias is not exhaustive, but merely reflective of the most common parasomnia types. If you believe you are experiencing a parasomnia, consult with your physician to learn about prevention tips and parasomnia treatment options.
There are many possible causes of parasomnia. The disorder might be associated with multiple triggers, including:
- substance use
- certain medications
- irregular sleep schedules, like shift work
- other sleep disorders, like insomnia
- sleep deprivation
- neurological conditions, like Parkinson’s disease
Parasomnia in children
Parasomnia affects more children than adults. It’s most common in children who have neurological or psychiatric conditions, such as epilepsy or ADHD.
Causes like stress and sleep deprivation can also trigger child parasomnia.
However, parasomnia in children usually happens because their sleep-wake cycle is immature. This means the boundaries between wakefulness and sleep are underdeveloped, resulting in a mixed state of consciousness.
Most children grow out of it by adolescence.
Compared to adults, children with parasomnia might experience more crying and fear. They might be scared to go to sleep alone.
If your child has abnormal sleep behaviors, remember that they’re not doing it on purpose. Focus on being supportive instead of punishing them.
For example, if they wet the bed, encourage them to use the bathroom before bedtime.
Aside from the unusual behavior during sleep, parasomnia can cause other symptoms. You might:
- wake up confused or disoriented
- wake up wondering where you are
- not remember doing certain activities
- find unfamiliar cuts on your body
- have difficulty sleeping throughout the night
- feel daytime sleepiness or fatigue
Your primary care doctor can help diagnose parasomnia. They’ll likely have you see a sleep specialist, who can further examine your sleeping behavior.
Diagnosis often includes:
- Medical history. Your doctor will ask about underlying medical conditions, current medications, family history, and lifestyle.
- Sleep history. A sleep diary can show your sleep behavior patterns. If you live with someone, they can observe how you sleep.
- Polysomnogram. In a Polysomnogram, you sleep in a lab overnight so a specialist can analyze your sleeping behavior. They’ll record your brain waves, breathing, and heart rate to make a diagnosis.
Parasomnia treatment depends on the type and severity. Your doctor might recommend the following:
If your parasomnia is frequent or recurring, medication can help manage it. The best choice depends on your symptoms.
Examples of medications used to treat parasomnias include:
- dopamine agonists
- benzodiazepines, like clonazepam
On the other hand, if your symptoms are actually due to a certain medication, your doctor might recommend an alternative medication or different dose. Don’t stop taking a medication without your doctor’s OK.
Cognitive behavioral therapy
Cognitive behavioral therapy(CBT) is a common parasomnia treatment. That’s because parasomnia is often related to mental health concerns, like stress and anxiety.
Other methods that may be used alongside CBT include:
- relaxation therapy
Some treatments can be done at home. Your doctor may suggest:
- Scheduled awakenings. Scheduled awakenings are when you wake up your child about 15 to 30 minutes before they spontaneously wake up. It may help minimize behaviors that follow a certain pattern. It’s often used for sleepwalking and night terrors.
- Safer sleep environments. If you sleepwalk or have RBD, you might need to sleep alone or remove dangerous items from your home. You can also lock windows and doors, place the mattress on the floor, and sleep with extra padding.
Parasomnia can make it hard to get quality sleep. It may also increase the risk of accidents and health problems due to lack of rest.
Fortunately, parasomnia is treatable, so it’s important to see a sleep doctor if you have unusual sleep behaviors. They can explore underlying causes and provide the best treatment for your symptoms.
- Schwab, R. (2020, June). Parasomnias. MERCK MANUAL Consumer Version.https://www.merckmanuals.com/home/brain,-spinal-cord,-and-nerve-disorders/sleep-disorders/parasomnias?query=parasomnia
- 2. Markov, D., Jaffe, F., & Doghramji, K. (2006). Update on Parasomnias: A Review for Psychiatric Practice. Psychiatry (Edgmont), 3(7), 69-76.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2958868/
- 3. American Academy of Sleep Medicine. (2014). International Classification of Sleep Disorders (Third Edition), 228-279 [E-book].https://learn.aasm.org/Users/Catalog.aspx
- 4. Office of Communications and Public Liaison, National Institute of Neurological Disorders and Stroke, National Institutes of Health. (2019, August 13). Brain Basics: Understanding Sleep. National Institute of Neurological Disorders and Stroke.https://www.ninds.nih.gov/Disorders/patient-caregiver-education/Understanding-sleep
- 5. Kierlin, L., & Littner, M. R. (2011). Parasomnias and antidepressant therapy: a review of the literature. Frontiers in psychiatry, 2, 71.https://doi.org/10.3389/fpsyt.2011.00071
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