What are parasomnias?

Parasomnias are events or experiences that disrupt sleep. They happen while a person is sleeping or going between different states of sleep (e.g., while trying to fall asleep or waking up). Parasomnias include disorders like:

• sleep walking
• sleep talking
• sleep eating
• nightmare disorder
• night terrors

What causes parasomnias?

The exact cause of parasomnias is not known.

While most people sleep, the nervous system is quiet and messages aren’t sent to the muscles. This is how the body protects itself, so a person doesn’t act out their dreams. With a parasomnia, the nervous system is “turned on” during sleep and messages are sent to the nervous system, muscles, or parts of the brain. Sometimes when this happens, a person acts out their dreams. Other times, the mind tries to make sense of this increased activity and creates experiences with the activity, so a person is “dreaming out their acts”.

Parasomnias happen most often when someone is waking up. They may be triggered by waking up suddenly from a deep sleep. The boundaries between sleep and being awake are blurred and parasomnias can happen during this time.

If someone is sleep walking, they'll suddenly wake up from a deep sleep. While sleepwalking, a person can do complex tasks because there is lots of brain activity like when the person is awake. But, the sleepwalker thinks they're still asleep. Other types of behavior can happen when the nervous system is active. For example, a person might drive somewhere, but not remember doing it for a few seconds or even minutes. In this case, the brain activity looks like the person is sleeping, but they can still do a complex task like driving.

Do I have a parasomnia?

A parasomnia is diagnosed based on your history. You'll need to see your doctor and talk about your sleep. You may then be referred to a sleep specialist.

You might need a sleep study to make sure you don’t have another health problem (e.g., seizures). But a sleep study can’t tell for sure if you have a parasomnia. If you have another type of sleep problem (e.g., sleep apnea), it can make a parasomnia worse.

Do I need treatment?

Most people don’t need treatment for parasomnias. Treatment may be needed if the behaviours:

• can harm the person or their partner
• or experiences are very hard for the person to deal with

The treatment depends on the type of parasomnia. It's most important to get good quality sleep. Being sleep deprived may increase how often parasomnias happen and sometimes increasing total sleep time or treating insomnia works well.

Stress may make parasomnias worse. For some people, lifestyle changes or cognitive behavioural therapy works well.

Sometimes medicines like clonazepam, some types of antidepressants, or seizure medicine is used to treat parasomnias. Your doctor will tell you what the best treatment is for you.

Types of Parasomnias

• Nightmare disorder: A person has scary dreams, which cause a faster heart rate, faster breathing, sweating, and waking up. A nightmare is different than a sleep terror because the person is completely awake afterwards and can remember the dream.
• Sleep terror disorder: Sleep terrors often cause extreme panic (e.g., a loud scream during sleep) followed by an activity like hitting things or moving in and out of the bedroom. Sometimes people have dream-like experiences with a night terror (e.g., seeing a snake or insect in the bed or shadows that look like someone is in the room). This is a disorder of arousal that happens most often during stage N3 of sleep.
• Sleepwalking disorder: Like night terrors, this happens during stage N3 of sleep. Sleep walking behaviours at times can be very complex. Some people remember parts of sleepwalking, while others don’t remember any at all.
• REM sleep behavior disorder: The person can act out their dreams, normally in a violent or physical way. For example, the person may dream of attacking ninjas and then start attacking their partner. REM behaviour disorder happens during REM sleep. It happens because the person’s muscles can move, which is not normal during this stage of sleep.