Parasomnias are abnormal events or experiences that disrupt the sleep and include unwanted perceptions, feelings, behaviors or movements. Parasomnias mostly occur during the phase of deep sleep but can also occur while falling asleep or waking up. People who have parasomnias usually don’t remember the events the next morning. Parasomnias may prevent you from getting a good night’s sleep and can affect your daily activities.

Parasomnias may be hereditary or triggered by stress, traumatic episodes, medications, alcohol or other sleep disorders.

The most common types of parasomnias include:

Confusional arousal: Acting in a strange and confused way when you wake up from sleep by a noise or some other stimulus. You are sluggish and may respond nonsensically to questions and have poor memory of the episode.

Sleepwalking: A parasomnia in which you arise from bed and move around or perform some activity in a state of sleep. Sleepwalkers are usually confused and angry if awoken and may respond aggressively if restrained. Sleepwalking can be dangerous as the sleepwalker is unaware of their surroundings and can injure themselves.

Night terrors: You awake in a fearful state, confused and unable to communicate as you are not fully awake. You fall asleep again after some time and are unable to remember the event the next day.

Nightmares: You may awake from an unpleasant dream and experience feelings of fear and anxiety. The person having a nightmare has difficulty going back to sleep and usually remembers the terrible dream.

Sleep paralysis: Sleep paralysis refers to the temporary inability to move that happens when you are going to sleep or waking up. During these episodes you will be unable to move or speak and may have hallucinations. Sleep paralysis may last a few seconds or minutes or may end when someone touches you or speaks to you.

REM sleep behavior disorder: People with REM sleep behavior disorder act out action and sometimes violent dreams and may hurt themselves or others.

Other parasomnias include sleep-related eating disorders, bedwetting, groaning, and sleep talking.

Parasomnias can occur in individuals of all age groups but sleep walking/talking and bed wetting are more common in children.

Potentially dangerous parasomnias or those affecting your health and daily activities require medical attention. It’s important to consult with a sleep specialist to evaluate and treat the condition. Your sleep specialist may ask you to maintain a diary of your sleep habits and will review your sleep symptoms. Your specialist may also ask about your medical and social history to identify the type of parasomnia and the associated cause. A sleep study such as a polysomnogram is conducted which measures breathing patterns, air flow, blood oxygen levels, electrical activity of the brain, heart rate, muscle activity and eye movements.

To treat parasomnia, your specialist may prescribe medication or recommend lifestyle changes or behavioral therapy. You will be instructed on safety measures to reduce the risk of injury associated with some types of parasomnias. Treating the underlying sleep disorder may help improve the symptoms of parasomnias.

Sleep Medicine of the Brain, Spine & Nerves