Sleep paralysis is classified as a REM-related parasomnia, and it describes a situation in which a person is not being able to move or talk, usually upon falling asleep or waking up. These episodes typically last only a few moments, but some are reported to last for a couple of minutes.
Often, sleep paralysis is accompanied by very vivid hallucinations, that can sometimes be terrifying. People described a pressure like somebody is sitting on their chest, and either seeing some frightening creatures, hearing them or sensing some presence in the room where they were sleeping. Throughout history, people have correlated these sleep paralysis episodes with demons, ghosts, and other mythical creatures, but today we know quite a few things about sleep paralysis and how to prevent it.
Most dreams occur during REM sleep. Thalamus is a brain structure that is in charge of getting the outside sensations from our senses and then sending them further to the cerebral cortex, where this information is interpreted and processed. Usually, the thalamus is inactive during most of your sleep, so you don’t get disturbed from the outside world. During REM sleep, however, it is very active, sending your cerebral cortex pictures, sounds, smell and, other sensations, and that is when your dreams happen. During this stage, your muscles are deeply relaxed, so that you don’t try to recreate your dreams and end up hurting yourself.
This process happens every night, whether you remember your dreams or not. But the problem occurs when you wake up during your REM sleep, and your brain doesn’t realize it. Your muscles are steel deeply relaxed, preventing you to move, and your mind is still in the REM stage of sleep, so that is why hallucinations may occur.
While this experience can be frightening and unpleasant, it doesn’t mean that there is some underlying problem with you, and sleep paralysis is mostly not a dangerous sleeping disorder.
As much as 8% of adults have reported experiencing an episode of sleep paralysis at least once in a lifetime. That number rises to 32% in psychiatric patients, and 28% in students. And even though it affects people of all ages, it is more common in teenagers and young adults, and it is less likely to happen as people age.
Sleep paralysis can affect the quality of your sleep, as some people will feel anxious to go to sleep because of the unpleasant episodes. In this article, we reviewed some of the most common symptoms and causes, as well as how to prevent, diagnose and treat sleep paralysis.
Most people experiencing sleep paralysis have reported one of these symptoms:
- Inability to move upon falling asleep or waking up
- Not being able to speak or move the eyes
- Difficulty breathing, described as somebody is crushing their chest
- A feeling of fear and dread
- Seeing or feeling an evil presence in the room
Causes and Risk Factors
Sleep paralysis occurs when rapid eye movement (REM) sleep happen while you are awake. Scientists are still not entirely sure why this happens, but several conditions are increasing chances of sleep paralysis occurring and are considered risk factors:
- Not getting enough (insomnia or sleep deprivation), or getting irregular sleep (jet lag, shift work)
- Increased levels of stress
- Sleeping on your back has been reported to induce more sleep paralysis episodes than other sleeping positions
- Having a sleep disorder, especially narcolepsy, sleep apnea, and shift work disorder
- Having a family history of sleep paralysis
- Use of hallucinogenic drugs and substance abuse in general
- Having nightly leg cramps
- Having a mental disorder, such as anxiety, depression, bipolar disorder, schizophrenia
When To See A Doctor
In many cases, sleep paralysis is a single accident, and it doesn’t happen again. It isn’t harmful and is usually not a sign of an underlying problem. However, you might want to see a doctor if:
- You experience episodes of sleep paralysis regularly
- You are struggling to get enough sleep, or you feel anxious to go to sleep
- You feel sleepy during the day, and sometimes suddenly lose muscle control or fall asleep. These can be symptoms of narcolepsy; a sleep disorder people sometimes suffer along with sleep paralysis.
Your doctor will give you sleeping tips to improve your sleeping habits or refer you to a sleeping specialist if your symptoms are more severe.
Even though sleep paralysis is mostly harmless, visiting a sleeping specialist is required if it affects your sleep.
The doctor will need to know when the sleep paralysis first started, how often it occurs, and how long the episodes last. They’ll also need to know your complete medical history, as well as past or present medication use.
You should also tell your doctor if you have ever had any sleep disorder. Try and find out if there’s anyone in your family with a sleep disorder, as they can also have a genetic background. People with a family history of sleep disorders are more likely to develop one themselves.
Sometimes, a doctor will ask you to fill a sleep diary for a few weeks. Keeping a sleep diary will help them get the needed information about your sleep patterns and habits, and give them an idea about what’s causing your problem, so they can advise you on how to correct it.
In most cases, that is all your doctor will need, but if your symptoms are more severe, you may be required to stay for an overnight sleep study called polysomnography.
Polysomnography keeps track of your brain waves, heart and breathing rate, the oxygen level in your blood, as well as eye movement. The sleep technician will also observe your body positions and actions, snoring and other noises you may make while sleeping. With this detailed data, a sleep specialist can diagnose any condition you might have, and give you the best possible treatment.
They might require an electromyogram (EMG) as well. EMG will show the level of electrical activity in your muscles, which is supposed to be low during the sleep paralysis.
If you experience a lot of daytime sleepiness, your doctor may request a daytime nap study called a Multiple Sleep Latency Test (MSLT). The MSLT will keep track of how fast you fall asleep when taking a nap and what kind of sleep you get during that time. These results can help your doctor determine if your sleep paralysis episodes are a sign of narcolepsy.
Treatment and Prevention
Sleep paralysis is usually harmless, so in most cases, it won’t require any special treatment. Treatment is mostly aimed at any underlying reason, if there is one of course, and it can include:
Improving your sleep habits. Getting sufficient sleep and avoiding sleep deprivation is very important. It is best to go to bed and wake up at the same time every day, and stick to that schedule as long as possible as it will improve the quality of your sleep.
Setting a comfortable bedroom atmosphere. It is crucial to feel comfortable in your bedroom, as that will help you relax and fall asleep faster. Remove any noises you may hear, leave nice neutral colors that will suit your eye, and set the right temperature. Also, avoid using bright and blue lights before bed, which means keeping your smartphone and laptop out of your bedroom.
Avoid using alcohol and cigarettes. These stimulants can mess with your natural daily rhythms and reduce the quality of your sleep.
Consider changing your sleep position. If you are sleeping on your back, you might want to consider switching to another position.
Exercise regularly. Remember that exercise improves the quality of your sleep. Try to exercise three to five times each week, but avoid doing it too close to bedtime, as it can be counterproductive.
In some more severe cases, the doctor will prescribe some antidepressant medications. These will alter your REM sleep and are usually used at a much lower dose than for treating depression.
Treating other sleep and mental disorders that are contributing to sleep paralysis is recommended.
The best thing you can do to prevent sleep paralysis from happening is to lead a healthy lifestyle with a healthy diet, exercise regularly and stick to good sleeping habits. If the sleep paralysis is occurring for the first time, try to stay calm during the episode, tell yourself that it will soon be over and probably won’t happen again. If the incidents continue, consider visiting your doctor.
Dusan is a biologist, a science enthusiast and a huge nature lover. He loves to keep up to date with all the new research and write accurate science-based articles. When he’s not writing or reading, you can find him in the kitchen, trying out new delicious recipes; out in the wild, enjoying the nature or sleeping in his bed.