Sleep is important for our physical and mental health, but this is hindered for millions of people due to unusual behaviors referred to as parasomnias. According to the American Academy of Sleep Medicine, approximately 10% of people will experience some form of parasomnia during their life, and many go undiagnosed.
The most common types of parasomnias include sudden, unintended movements while sleeping, or, possibly, experiencing some form of hallucination. Parasomnias can disrupt sleep in adults and children, with the possibility of confusion, poor sleep, and safety concerns afterward.
In this blog, we will outline many of the different types of parasomnias, some symptoms that one might see, and current treatments to help avoid or minimize these disruptive sleep behaviors.
What is Parasomnia?
Parasomnia is a category of sleep disorders involving abnormal movements, behaviors, emotions, perceptions, or dreams that occur while falling asleep, during sleep, or during arousal from sleep. Parasomnias can disrupt sleep and can sometimes create the possibility of harm to oneself or another person, especially when movements are involved (sleepwalking, or acting out dreams). Parasomnias are generally classified by the sleep stage during which they occur (NREM or REM).
Types of Parasomnias
Parasomnias are typically classified based on the sleep stage in which they occur—NREM (Non-Rapid Eye Movement) or REM (Rapid Eye Movement) sleep. Some parasomnias can also occur during transitions between sleep and wakefulness. Here's a breakdown of the main types:
1. NREM-Related Parasomnias
NREM-related parasomnias occur during the deep stages of Non-Rapid Eye Movement (NREM) sleep, usually in the first third of the night. These episodes often involve incomplete awakenings where the person may appear confused, disoriented, or even engage in complex behaviors—without full consciousness or memory of the event.
Common features include:
- Sudden arousals with confusion or fear
- Partial awareness with no recollection afterward
- Physical behaviors like sitting up, walking, or talking
These are more common in children, but adults can experience them too, especially under stress or sleep deprivation.
2. REM-Related Parasomnias
REM-related parasomnias happen during Rapid Eye Movement (REM) sleep, the stage when most dreaming occurs. Normally, the body is temporarily paralyzed during REM sleep to prevent dream enactment—but in REM-related parasomnias, this mechanism fails.
Key characteristics include:
- Vivid, often disturbing dreams
- Physical movements like kicking, punching, or shouting
- Full recall of dream content upon awakening
These disorders are more prevalent in older adults and may sometimes be linked to neurodegenerative conditions like Parkinson's disease.
NREM-Related Parasomnias
These usually occur during the deeper stages of NREM sleep (typically in the first third of the night):
Sleepwalking (Somnambulism)
Sleepwalking involves getting up and walking around while the person sleeps quite deeply. They might do stuff to get dressed, move things, or leave the house, without awareness that anything has happened. Sleepwalking usually occurs during the first few hours of the night and is more prevalent in children, but in adults it can occur due to stress, drinking alcohol, or lack of sleep.
Sleep Terrors (Night Terrors)
Night terrors are abrupt episodes of intense fright, kicking, screaming, or flailing while sleeping that are often accompanied by a rapid heartbeat or sweating. Unlike nightmares, the person never wakes completely, and they almost never have any memory of the incident. Night terrors are most prevalent in children and usually occur during the first few hours of the night during deep sleep.
Confusional Arousals
During a confusional arousal, a person wakes from deep sleep completely confused and fundamentally disoriented. They may sit up, mumble, or look awake but are not responsive or awake in a conventional sense. A confusional arousal can last for several minutes and usually has no memory of the arousal after it is over. A confusional arousal can often be preceded by sleep deprivation, sleep disruption, and stress.
Sleep-Related Eating Disorder (SRED)
Sleep-Related Eating Disorder (SRED) involves episodes of eating or drinking during partial arousals from sleep—that is, during sleep with little to no awareness. It can involve ingesting unusual or even inedible things, and the behavior may lead to excessive weight gain, injury, or health problems. SRED is more common in women and may occur with other sleep disorders or after routine use of sedatives.
REM-Related Parasomnias
These occur during REM sleep, often involving vivid dreams:
REM Sleep Behavior Disorder (RBD)
Rem Sleep Behavior Disorder (RBD) occurs when the normal paralysis that happens during rem sleep is absent, allowing a regular sleeper to physically act out their dreams. The acts can involve kicking, punching, jumping out of bed, or shouting. The sleeper may injure themselves or their bed partner. RBD is more common in men over 50 years and may be an early indicator of neurologic diseases such as Parkinson's or Lewy body dementia.
Nightmare Disorder
Nightmare Disorder involves recurring vivid or disturbing dreams that typically awaken the dreamer and leave him or her feeling anxious, fearful or upset. Unlike night terrors in which the person remains asleep during and until they must re-orient themselves in the morning, the person with Nightmare Disorder will wake fully and often recall the dream in great detail. Chronic nightmare disorder can impair sleep quality or be triggered by stress, trauma, or certain medications.
Sleep Paralysis
Sleep paralysis is a temporary inability to move or speak while falling asleep, or waking up, with the mind awake. Each 'episode' of sleep paralysis can last from a few seconds up to a few minutes. Sleep paralysis can be accompanied by visual and auditory hallucinations and a feeling of pressure on the chest.
Sleep paralysis can be frightening, but is typically harmless. The episodes are most common during periods of increased stress, difficulty sleeping, or irregular sleep patterns.
3. Other Parasomnias
These don’t fit neatly into the NREM or REM categories and may occur during transitions:
Exploding Head Syndrome
A harmless but disturbing state where a person hears a sudden loud sound—like an explosion or crash—while they transition into or out of sleep. There is no sound, and sometimes the sound is associated with light or a jolt. It is not dangerous, but it can induce anxiety and disrupt sleep.
Sleep Enuresis (Bed-wetting)
Involuntary urination while sleeping is a condition almost always associated with children but can be found in adults. Bed-wetting in adults may be genetically associated, or related to events that increase stress, and other medical conditions, or sleep cycle of varying depths. Most children will outgrow bed-wetting, however, persistent cases may warrant medical intervention.
Sexsomnia
This parasomnia is rare, and involves the engagement in sexual acts—such as masturbation, petting, and intercourse—while asleep, with no recollection of the event after, often associated with other parasomnias like sleepwalking, and may cause legal or relationship issues.
Sleep Talking (Somniloquy)
Talking during sleep, or somniloquy, can occur without the person being aware they are talking. Talking can include speech from basic sounds to complex conversations. It isn't harmful, but could be disruptive to people sharing a bed, and may occasionally indicate stress or sleep disorders.
What are the Symptoms of Parasomnia?
- Unusual movements or activities while sleeping - Movements may include walking, sitting up, or doing activities while not fully awake.
- Sitting up or getting out of bed with a confused look on their face - Individual is not awake or aware, may appear awake but is usually unresponsive.
- Nighttime screaming or emotional episodes - Sudden terror or screaming - common in night terrors.
- Physical aggression or arm flailing while sleeping - physical actions occur during sleep; REM sleep behavior disorder; potentially dangerous to self or others.
- Dream-enactment behavior - sleeper engaged in active dream; expresses intense emotions; for example: someone dreams of going to work but grabs their work equipment and leaves or someone can-engaged in persistent violence to dream, while looking sleeping but expressing physically.
- Sleep-related sexual activities with no recall - includes sexual behaviors while sleeping-fondling, sexual intercourse with no recall.
- Bed-wetting (Sleep Enuresis) - involuntary urination while sleeping, beyond early childhood. Confusing wake-up - waking up with fogginess, confusion about where they are or what they did when they were asleep.
- Serious injury to the self or bed partner while sleeping - parasomnia episodes can involve unintentional injury to self or others.
- Sleep talking, mumbling, shouting while sleeping - talking or communicating while sleeping; range from mild to intense, soft mumbling to yelling.
- Sudden awakening in distress or panic - waking up from sleep in fear or panic, commonly related to night terrors.
- Poor recall of the event upon waking - Most people recall very little or nothing at all about the parasomnia event.
- Excessive daytime sleepiness - Disturbances during sleep may result in poor sleep quality and thus cause sleepiness during the day.
- Hallucinations during sleep transitions - Visual and/or auditory hallucinations may occur while falling asleep or arousing.
- Recurrent nightmares or unsatisfying dreams - Distinct, recurrent bad dreams that interrupt sleep and/or disturb sleep as they are woken with distress feelings associated with the dream.
Causes of Parasomnias
Parasomnias can be caused by many different factors that disrupt regular sleep architecture or brain function during sleep. Some common causes of parasomnia include the following:
1. Sleep Deprivation: Insufficient sleep raises the risk of abnormal sleep behaviors, particularly during deep NREM sleep.
2. Stress and Anxiety: High levels of emotional stress or anxiety can distort normal sleep architecture, contributing to more parasomnia episodes.
3. Genetics: If someone has a family history of parasomnias (particularly sleepwalking or night terrors), this could put them at higher risk, particularly in children.
4. Breaching of Medications and Substances: Some medications such as sedatives or antidepressants, alcohol or recreational drugs can both trigger and exacerbate parasomnias.
5. Poor or Irregular Sleep Schedules: Changing your bedtime frequently or working shift work can disrupt your circadian rhythm and increase risk.
6. Sleep Disorders: Parasomnia episodes are often associated with sleep disorders including obstructive sleep apnea (OSA), restless leg syndrome, and insomnia.
7. Neurological Conditions: Parasomnia may also be associated with certain brain disorders such as epilepsy, Parkinson's disease, or dementia, particularly REM sleep behavior disorder (RBD).
8. Fever and or Illness: High fevers, particularly in children, can lead to night terrors or hallucinations during sleep.
9. Environmental Triggers: Noise, light, or being awakened suddenly can interrupt normal stages of sleep and elicit parasomnia behaviors.
Factors that Trigger Parasomnia
Here are some everyday life factors that can trigger parasomnia:
- Stress from work or personal life
- Irregular or insufficient sleep
- Consuming alcohol or caffeine close to bedtime
- Taking certain medications like sleeping pills or antidepressants
- Using electronic devices late at night (blue light exposure)
- Sleeping in an unfamiliar environment
- Sudden loud noises during sleep
- Skipping meals or eating late at night
- Physical exhaustion or overexertion during the day
- Changes in daily routine or travel (jet lag)
Treatment of Parasomnia
Treating parasomnias typically involves a combination of lifestyle changes, safety measures, and sometimes medical interventions, depending on the severity and type of the disorder.
- Improving Sleep Hygiene
Establishing regular sleep schedules, creating a calm bedtime routine, and ensuring a comfortable sleep environment can reduce episodes. Here are some essential tips for better sleep hygiene.
- Managing Stress and Anxiety
Techniques like meditation, therapy, or relaxation exercises can help lower stress levels that may trigger parasomnias.
- Medication
In some cases, doctors may prescribe medications such as benzodiazepines, antidepressants, or melatonin to manage specific parasomnias.
- Treating Underlying Sleep Disorders
Addressing conditions like sleep apnea or restless leg syndrome can often reduce parasomnia episodes.
- Safety Precautions
For behaviors like sleepwalking, securing the sleeping area to prevent injury is essential—locking doors and windows, removing sharp objects, and using bed alarms if needed.
- Behavioral Therapy
Cognitive-behavioral therapy (CBT) or scheduled awakenings may be recommended, especially for children or those with frequent episodes.
- Avoiding Triggers
Limiting alcohol, caffeine, and certain medications, and minimizing sleep disruptions can help control symptoms.
Is there a Cure for Parasomnia?
While parasomnias are not typically "cured," many cases can be managed and improved with the right approaches and lifestyle modifications. For some people—especially kids—parasomnias like sleepwalking or night terrors will sometimes remit on their own when the brain develops.
In adults, managing underlying causation, like stress, sleep disorders, or side effects of medication may reduce or stop episodes entirely. In cases like this, medications or therapeutic behavioral modalities can help control symptoms for a prolonged duration of time.
Although it is often not possible to completely "cure" parasomnias, many people manage to achieve restful, safe sleep through the use of various suggestive strategies, as well as addressing the parasomnia itself.
How to Diagnose Parasomnia?
Diagnosing parasomnia involves a thorough evaluation of sleep habits, medical history, and sometimes specialized testing. Here’s how the process typically works:
1. Clinical History
Your healthcare professional will discuss in-depth information about your sleep patterns, sleep behaviors, daytime symptoms, family history, and possible triggers, such as stress, medications, and substances. If you have a partner in bed or someone sleeps with you, they may be asked for their input during this portion.
2. Sleep Diary or questionnaire
Your healthcare provider may ask you to keep a sleep diary for one to two weeks to track your sleep-wake cycles (when you wake, when you sleep, any behaviors, and if there are any abnormal events). They may also utilize questionnaires (Ex. Epworth Sleepiness Scale) regarding sleep quality and daytime sleepiness.
3. Physical and Neurological Exam
The doctor may perform a physical exam to rule out potential other medical or neurological conditions contributing to the symptoms
4. Polysomnography
If the episodes are severe, dangerous, or it isn't clear what is occurring, your provider may refer for a polysomnography, or sleep study. While you are asleep, the study can measure brain waves, heart rate, breathing, eye movement, and muscle movement. This will allow the provider to observe or find abnormal behaviors, and what stage of sleep the behaviors occur in.
5. Video Monitoring
Any of the above studies can also use video EEG or infrared video to record what is occurring physically during the episodes, especially when the parasomnia episodes are complex or resemble seizures.
When to Consult with a Doctor?
You should see a health-care professional for parasomnia if it is occurring often, is intense, or is potentially destructive. This includes behaviors such as sleepwalking, night terrors, or acting out dreams that result in harm or injury to yourself or someone else.
Other signs to consult a doctor for parasomnia include excessive daytime sleepiness also known as Hypersomnia, impaired concentration, and feeling tired even after sleeping—that is a huge indication that your sleep is disrupted, either from an unidentified parasomnia or another sleep disorder. An early assessment can help identify underlying issues, leading to adequate treatment and preventing more serious outcomes.
Final Thoughts
Parasomnias can be unsettling—for both the person experiencing them and those around them—but they are more common than many realize and often manageable with the right approach. Understanding the types, symptoms, triggers, and treatment options is the first step toward regaining control over your sleep.
Whether caused by stress, irregular routines, or underlying health conditions, these sleep disturbances should not be ignored. With proper diagnosis, lifestyle adjustments, and in some cases medical support, most people can significantly reduce or even eliminate parasomnia episodes—leading to safer, more restful nights and healthier days.
