Most of us spend about a third of our lives sleeping. Yet for something that we do so much, there are surprisingly a lot of things about it that we don’t know. There are entire clinics dedicated to helping people with sleep disorders and a large amount of scientific research focusing on all the amazing things that happen after we’ve dozed off.
Sleep is important for so many reasons and a lot goes on in your body and brain while you sleep, though it may not look like it at first glance. Here are 15 weird things that happen when we sleep.
15 You Purge Useless Information
The amount of information that the brain is bombarded with every day is countless. As soon as you step outside each morning, your brain immediately takes in the colors of everything around you, the sounds of passerby talking and a lot of other information that you don’t really need to remember. If you did remember it all, your brain would be overwhelmed and you’d probably have a hard time recalling information since there would be so many pieces to search through. Luckily, your brain sorts information while you sleep and forgets the things you don’t need to remember.
14 You Move Your Eyes Rapidly
If you’ve ever looked closely at someone sleeping, you may have noticed their eyes moving beneath their closed eyelids. Kinda creepy, isn’t it? Your eyes move quickly from side to side during the period of sleep known as REM (Rapid Eye Movement), which makes perfect sense. This is the phase where dreaming occurs and your eye movements correspond to experiencing a change of scene or concept within your dreams. This isn’t the same thing as looking around (or scanning) the scene in your dream, but has to do more with the brain activity that occurs when a concept changes. This explains why even blind individuals experience eye movements during sleep!
13 You Lose Weight
Sleeping is like going on a small fast. You don’t consume anything while asleep but you lose water through sweating and breathing out humid air during the night. This causes some weight loss, especially if you’re getting a full seven or eight hours of sleep. In fact, while sleeping, the average person burns about 60 calories per hour. This can equate to the loss of about 1/10 of a pound. It may not be much, but it all adds up in the end, if you stick with a healthy diet and exercise regime.
12 You Become Paralyzed
During REM sleep, which is a period of deep sleep in which dreams occur, the muscles in your arm become temporarily paralyzed. This is actually very useful. Can you imagine if your arms weren’t paralyzed and you had a dream about punching someone out while sleeping next to your partner? They probably wouldn’t be too happy about that. While this temporary paralysis happens to everyone, there are a few people who have a disorder called sleep paralysis, in which the paralysis lasts a few minutes after waking. It isn’t dangerous but understandably it’s a bit scary for those who experience it. The number of sleep paralysis episodes a person has can be reduced by getting sufficient sleep and reducing stress.
11 You Solve Your Problems
Have you ever gone to bed unable to complete a challenging math question, only to wake up with the answer all of a sudden? This is surprisingly not uncommon and could explain the phrase "sleep on it." While you may think that your brain is resting while you’re asleep, it’s actually working to solve the problems you may worry about during the day. Researchers believe that sleep allows you to access a network of associations in your brain that may help you to solve the problem (this is known as spreading activation).
Another theory is that dreams may serve the purpose of helping us to solve the difficult problems that we face while awake. Since dreams are highly visual, they allow for “out-of-the-box” thinking that certain problems require. There have even been studies which show that sleeping on a problem, at least relatively easy ones, is effective. It’s pretty cool to know that while we may have given up on a problem, there’s another side to us that keeps going.
10 Your Sense Of Smell Plummets
You may wake up to the sweet smell of a delicious breakfast and some coffee, but those sweet scents can’t wake you up. That’s because we cannot smell while we’re asleep. The exact reason for this is unclear, though it may be a result of loss of contextual cues. This is why it’s so important to have a smoke detector. Even if the fumes are intense, you won’t be able to smell it if you’re sleeping. Oddly enough, some people do dream of scents, but these scents are created by the brain.
9 You Pass Gas Easier
When you’re sleeping, your body relaxes and muscles loosen up. Unfortunately, this applies to your anal sphincter muscles, too. This makes it easier for gas to pass. That might make you a bit self-conscious the next time you’re about to go to bed with your significant other. But, luckily our sense of smell is gone while we’re asleep!
8 Your Dreams Keep Repeating
Have you ever had the same dream over and over again? Perhaps during college exams each semester, you’ve dreamed about sleeping in and missing an exam or blanking out while writing. Don’t worry, you’re not alone on this one. Many people experience recurring dreams and maybe it’s time to start paying close attention to those dreams. It’s believed that recurring dreams represent unresolved problems we face in our waking life. While the recurring dream may not be specific to what’s going on in your life, it likely has themes that are relevant. For example, long after you finish college, you may still dream of missing an exam whenever you’re worried about failure in your career. Keeping track of your dreams and learning to face the unresolved problems they represent can definitely be useful and therapeutic.
7 You Think You're Falling
A common, but weird, thing that happens to 70% of people is the feeling of falling just before going to sleep or waking up. Also known as hynic jerks, the sleep disturbance may be caused by remaining daytime energy that bursts out in random movements. Alternatively, they may be caused by confusion of the brain, in which the brain thinks you’re falling since your muscles are relaxing and responds by causing them to tense, so as to “catch yourself.” But it remains unclear as to which, if any, of these theories is accurate.
6 You Release Growth Hormones
There are many reasons why as kids we were told to go to bed early so that we could get a full night’s rest. One of these reasons was so that we could grow and develop. When we sleep, the secretion of growth hormone, by the pituitary gland in our brain, spikes. This hormone is responsible for muscle and bone growth, obviously. It’s also important in regulating sugar and fat metabolism and in stimulating collagen, which keeps your skin youthful-looking. Now the term “beauty rest” makes sense, doesn’t it?
5 You May Even Walk
Maybe you or someone you know sleepwalks, as 1-15% of Americans do. It usually occurs early in the night, when your body has fallen into a semi-conscious state, just before REM sleep. Scientists are still trying to figure out what causes some people to sleepwalk and not others. People do all sorts of things while sleepwalking, from walking down the hall to driving a car! Most of the behaviours are part of their routine, such as going downstairs to grab a bite. Clearly, sleepwalking has the potential to be dangerous, so you should actually wake a person who is sleepwalking, contrary to popular belief.
4 You Might Talk Too
About 5 percent of the population talks in their sleep, but the relatively harmless disorder is more common in children than adults and in men than women. Most people don’t remember the things they say while sleeptalking, but most of us know from experience that things can get pretty weird! Sleeptalking can happen in any stage of sleep, and may get triggered by stress, depression, illness or other sleep issues like sleep apnea.
3 Or You Could Just Text Instead
Something that’s fairly new, thanks to the advent of excessive texting, is sleeptexting. Yes, the dreaded nightmare of sending a text to the wrong person is actually a constant reality for some people when they go to sleep. It’s a growing phenomenon in teenagers and those who constantly feel “on call” during the day. One tip for avoiding this potentially disastrous experience is to keep your phone out of your bedroom during the night (or at least some distance from your bedside).
2 You Think Your Head Exploded
You may not have even heard of exploding head syndrome, but it’s one of the weirdest things that can actually happen when we sleep. People who experience this bizarre phenomenon hear loud, imagined sounds (such as a bomb exploding) just before falling asleep or waking up. That must be pretty scary! In fact, sufferers of this syndrome often have high levels of distress and fear. It’s believed that instead of shutting down properly before sleep, the brain cells responsible for sound fire all at once, creating a blast of energy that the brain interprets as a loud noise. Fortunately, exploding head syndrome is not very common.
1 You Become Aroused
You might think that dreaming about your fantasies is what causes arousal while you’re sleeping, but there’s a more scientific explanation to the phenomenon. During REM sleep, your brain is so active that it requires more oxygen. As a result, the blood flow to your body increases. And you know what a rush of blood down below means. Both men and women may become aroused while sleeping. In rare cases, some people even have sex or engage in sexual behaviours while sleeping, a condition known as sexsomnia. Though the exact causes of this condition are unknown, perhaps being naturally aroused during sleep is a trigger for some.