Lots of people know that dreaming tends to occur during REM sleep. What many people do not realize however, is that when we are in REM sleep our bodies are paralyzed. It’s Mother Nature’s protection mechanism to keep us from acting out our dreams. It is a good thing that this happens because it allows us to remain peacefully in our beds as our dreams play out.
There are a few people in whom this protection mechanism does not work and they are free to swing their arms as they enjoy an afternoon swim in their dream. This is called REM Behaviour Disorder or RBD for short. It is often very dangerous and the person with the disorder usually ends up injuring themselves. In one case study, we saw a patient who dreamed that he was playing baseball. As he slid into home plate in his dream, he actually dove into his dresser — head first! He woke up in a pool of blood and ended up with 39 stitches across his forehead.
People with REM Behaviour Disorder will often hurt their bedpartners without meaning to do so. They will punch them, grab them, kick them and even try to strangle them. It is the bedpartner who is usually the first to notice these unsettling behaviours. The person with the disorder often has no recollection of the event in the morning. They may wake up with their feet on the pillow and their blankets in a mess, yet they do not remember how they got that way.
REM Behaviour Disorder is not the same thing as sleepwalking. Sleepwalking is most common in children and occurs during the deepest stages of sleep, stages 3 & 4, usually in the first-third of the night. Our bodies are not paralyzed during stages 3 & 4 and that is why we are able to get up and walk around. There is usually no dream recall when someone sleepwalks. With REM Behaviour Disorder on the other hand, people can recall a dream if you wake them up during the episode. Since REM is most prominent in the second half of the night, most of the RBD episodes happen in the early morning hours. REM Behaviour Disorder is most common in elderly individuals, particularly males over the age of 60.
Some common themes that have been reported by REM Behaviour Disorder sufferers are dreams of fishing, shoveling snow, delivering a speech, and running away from something. The first signs noticed by bedpartners are often talking, laughing, singing, chanting, reaching, yelling, jumping, swearing, sitting up, flailing arms and kicking legs. Imagine lying next to someone with REM Behaviour Disorder who was dreaming they were Karate fighting and suddenly you find that you are the opponent. Ouch!
It is important to note that although they can be violent in their sleep, REM Behaviour Disorder sufferers are not usually violent individuals and they don’t mean to hurt their bedpartners. Someone who suspects that they have this disorder should be referred to a sleep lab for proper diagnosis and treatment. Often times there is a disorder of the central nervous system involved which will need further investigation. There are medications which can help by inhibiting muscle activity during REM sleep. In the meantime, there are other precautions which you should take:
- It is important that the sleep environment be secure.
- Try to move objects away from the bedside.
- Place a mattress on the floor next to the bed to help cushion any falls.
- Bedpartners should consider sleeping in another room for their own safety.
- Restraints have sometimes been used. People have used belts and/or rope to tie themselves into bed. Still however, many manage to escape these restraints by dreaming of undoing the ropes.
Here’s a typical case study:
A patient came to the sleep laboratory because he was keeping his family awake all night with shouting and jumping around in bed. His wife was forced to sleep in a different room not only to get some sleep, but also because she feared for her own safety. The patient managed to fall out of bed on a nightly basis, often injuring himself in the process. He was a war veteran and would dream of trying to avoid enemy attack. Thinking that it would help, he purchased a hospital bed with railings. Still he managed to climb out over top of the railings and fall to the floor night after night. Finally, the patient had to resort to sleeping on a mattress on the floor. When he was monitored in the sleep lab, and he entered REM sleep, abundant muscle tone was detected when it should have been absent. Talking, laughing, shouting, flailing of the arms and kicking of the legs were all observed. He nearly fell head first out of the bed on several occasions that night. For treatment, the patient was prescribed a medication which makes his muscles relax during REM sleep so that he will no longer acts out his dreams. The patient is now doing fine and is again sleeping with his wife in their bed.
Thanks to L. Orr, BA, RPSGT for her help with this article.