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Surprising sleep myths and facts you should know

That little jump you do while falling asleep has a scientific name.

Amanda Capritto
5 min read
Charles O'Rear/Getty Images

Sleep is complex, interesting, abstruse and sometimes just weird. Isn't it strange that we all fall into a slumber for several hours each night? What's especially strange is that sometimes sleep comes easy and sometimes it takes hours to fall asleep; sometimes you toss and turn and sometimes you wake up in the same position you started in. Sometimes you remember your dreams and sometimes you don't. Those aren't the only weird things about sleep -- these quirky sleep facts will make you raise an eyebrow. 

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Myth: If you remember your dreams, it means you slept better

Many people believe that remembering their dreams means they had a good night's sleep. That's not necessarily the case, says Ariel Garten, co-founder of Muse, a neuroscience and meditation company. People actually remember dreams when they're woken up during them, she says, which indicates poorer sleep. It also has something to do with sleep stages: You're more easily woken up during REM sleep, which is when dreams happen, Garten says. 


Remembering your dreams doesn't always mean you slept better.

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Myth (sort of): You can die from not sleeping

It's unlikely for sleep deprivation to be a cause of death, but sleep deprivation can increase your chances of death because of effects like immune system suppression and increased risk of vehicle accidents. There is one medical condition linked to death from sleep deprivation called "fatal familial insomnia," which involves degeneration of the central and autonomic nervous systems, but this condition is genetic and extremely rare

In the past, gamers have died during gaming marathons of 20-plus hours, but their deaths are usually attributed to something else -- not sleep deprivation -- such as one gamer in Taiwan who died of cardiac arrest during a gaming marathon. In other cases, the cause of death isn't specified.

Fact: Dreams are like file cabinets for your brain


When you dream, your brain processes, stores and trashes information.

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Dr. Shelby Harris, a licensed psychologist board-certified in behavioral sleep medicine, tells CNET that dreaming is your brain's way of filing away important tidbits of information for later. "A lot happens during the day, and our brains have a clear-cut way of trying to figure out what to make a file to have for the future, should we need that info again," she says. 

"Dreaming is the brain's way of consolidating emotions, memories and cognitive experiences into a nice, neat file and shredding what we don't need," Dr. Harris explains. "While dreams are often jumbled, pieces of them tend to represent what might be going on." 

Fact: Humans didn't always sleep in one chunk of time at night

Humans used to engage in biphasic sleep, or two sleep "shifts" rather than one long chunk of sleep. Some anthropologists and historians believe the invention of electricity and increasingly standardized work and school schedules (i.e., 8-hour days, as originally stipulated by social reformer Robert Owen) influenced our current sleep behavior. 


Single-phase sleep wasn't always a thing.

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Fact: Deep sleep cleans your brain

Every time you fall asleep, your brain takes a shower -- in a sense. During sleep, your brain "washes away" toxins and waste by flushing cerebrospinal fluid in and out in a wave-like manner. This process is thought to promote healthy cognitive function, which just adds one more reason to prioritize sleep. 

Fact: Some people can thrive on less than 6 hours of sleep

Researchers have discovered a "short sleep gene" that appears in people who can sleep for just a few hours each night with no ill effects. It's possible that many high achievers, such as CEOs and other leaders, have this gene. 

Fact: Einstein reportedly got 10 hours of sleep per night

Take it from Einstein: Good sleep is key to smarts and success. Unless you're Nikola Tesla

Fact: More sleep isn't always better

Most sleep research shows that both short and long sleep durations are associated with higher overall mortality, says Annie Miller, psychologist at DC Metro Sleep and Psychotherapy. Oversleeping can lead to health complications just like undersleeping can. "This information can go a long way when people are worrying about not getting enough sleep and how it will impact them long term," she says. 

Myth: You can 'catch up' on missed sleep

Speaking of more sleep, Miller explains that catching up on sleep is a modern fantasy. "Some people try to make up for sleep lost during the week on vacations or holidays, but this doesn't work," she says. "Our brain thrives on habit and routine. If we vary our wake times, we create what's called 'social jet lag' and this actually makes the sleep problem worse."

Fact-ish: Some people dream only in black and white


Older generations reported dreaming in only black and white.

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In 2008, a research study found older adults to dream in black and white more than younger people. Specifically, the paper says adults 55 and older reported dreaming primarily or only in black and white, while people 25 and younger report almost never dreaming in black and white. This might have something to do with exposure to color television because in the 1940s, 70% of participants in a study said they dream only in black and white. Or, those people are just "profoundly mistaken" and only remember their dreams in black and white.

Myth: You shouldn't wake someone who is sleepwalking 

Conventional wisdom tells us to leave sleepwalkers alone to do their thing, as it could be dangerous to wake them. But the National Sleep Foundation says sometimes waking a sleepwalker is necessary, such as in cases where the sleepwalker endangers themself or others. If you can, it's best to guide the sleepwalker back to their bed without waking them, the National Sleep Foundation says.  

Fact: Fear isn't the main emotion in nightmares

Research shows that more people report feeling confusion, disgust, guilt and sadness during bad dreams, not fear. Anxiety is also a common emotion people feel during bad dreams and nightmares. 


Scary dreams often involve more confusion than fear.

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Fact: Some people are afraid of falling asleep

Somniphobia, also called hypnophobia and sleep dread, is the fear of falling asleep or sleeping itself. Don't confuse this with insomnia, which is the inability to fall asleep. Someone with somniphobia may experience severe anxiety about going to bed. 

Fact: Sleep deprivation is a treatment for depression

While most of us worry about not getting enough sleep, science shows that deliberate sleep deprivation can alleviate depressive symptoms. Researchers don't yet understand the biological mechanisms behind this, but there's clearly a link.  

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Fact: No one knows if your brain can create unique dream people

You may have heard someone say your brain can only dream about people or combinations of people it's seen before -- that it can't create new and unique people. This is an enthralling theory, but there's no sound way to know if it's true, according to Stanford University. 

Fact: Twitches while falling asleep are called 'hypnic jerks'

If you've ever jerked yourself awake just as you were settling into sleep, you've experienced a hypnic jerk. These twitches are relatively common, affecting about 60 to 70% of people, researchers estimate. They're totally harmless, unless you twitch so hard you fall out of bed.

The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.