Parasomnias
What are they?
Parasomnias are a group of sleep disorders characterized by undesirable physical events, behaviors, movements, emotions, perceptions, or dreams that occur while falling asleep, during sleep, or while waking up.
During these episodes, the brain is caught in a state between full sleep and wakefulness.
Parasomnias are divided into two main categories based on the stage of sleep in which they occur:
Non-REM (NREM) Parasomnias — occur during deep sleep, usually in the first half of the night:
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Sleepwalking: Walking or performing complex activities while still asleep.
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Sleep terrors (night terrors): Sudden episodes of intense fear, screaming, and agitation during sleep, with no memory of the event.
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Confusional arousals: Waking up confused and disoriented, sometimes with inappropriate behavior.
These are very common in children (ages 2–12) and usually resolve with age. They can occasionally persist or begin in adulthood.
REM Parasomnias — occur during dream sleep (REM), usually in the second half of the night:
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REM Sleep Behavior Disorder (RBD): Acting out vivid, often intense dreams by talking, yelling, punching, kicking, or jumping out of bed. Unlike sleepwalking, people with RBD can often recall the dream. RBD is most common in adults over 50 and can be an early sign of neurological conditions such as Parkinson's disease.
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Sleep paralysis: Briefly being unable to move or speak when falling asleep or waking up.
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Sleep-related hallucinations: Vivid, dream-like experiences that occur when falling asleep or waking up.
How are they diagnosed?
Most parasomnias are diagnosed based on a detailed description of the events, often with input from a bed partner or family member. An overnight sleep study (polysomnography) with video recording may be needed, especially to diagnose REM sleep behavior disorder or to rule out seizures.
How are they treated?
Safety first: Making the sleep environment safe is the top priority — removing sharp objects, placing the mattress on the floor, locking doors and windows, and using bed alarms if needed.
Address triggers: Sleep deprivation, stress, alcohol, and certain medications can trigger episodes. Treating other sleep disorders (like sleep apnea) that fragment sleep can also help.
Scheduled awakenings (for children): Waking the child about 15–30 minutes before episodes typically occur can be effective for sleepwalking and sleep terrors.
Reassurance: In children, NREM parasomnias are usually harmless and outgrown. No treatment is needed in most mild cases.
Medications: For frequent or dangerous episodes, medications such as clonazepam or melatonin may be prescribed, particularly for REM sleep behavior disorder.
FAQs
Most episodes are harmless, but there is a risk of injury from falls, walking into objects, or leaving the house.
Safety precautions are important.
It is generally better to gently guide them back to bed rather than forcefully waking them, which can cause confusion and agitation.
Yes. RBD in older adults can be an early sign of Parkinson's disease or related conditions. A neurological evaluation is recommended so that any emerging symptoms can be monitored and addressed early.
In most cases, yes. Night terrors are very common in young children and typically resolve by adolescence.