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  • Ah, sleep!

  • You can never have enough of it, it seems.

  • In fact, sometimes it literally feels like you aren't getting enough.

  • But what if you stopped sleeping altogether?

  • Strangely, science understands relatively little about why we sleep or how it evolved in the first place.

  • After all, laying unconscious and dormant for hours on end while predators lurk hardly seems advantageous or smart.

  • But we have discovered a few correlations.

  • For example, adults who sleep between six to eight hours a night tend to live longer.

  • Excessive sleep, however, can lead to medical problems, including cardiovascular disease and diabetes.

  • Similarly, chronic sleep deprivation has been linked to aspects of cardiovascular disease, obesity, depression, and even brain damage.

  • But what if you stopped sleeping right now?

  • Well, after your first sleepless night, your mesolimbic system becomes stimulated, and Dopamine runs rampant.

  • And this may actually trigger some actual energy, motivation, positivity, and even sex drive.

  • Sounds appealing, but it's a slippery slope.

  • Your brain slowly begins to shut off the regions responsible for planning and evaluating decisions, leading to more impulsive behavior.

  • Once exhaustion sets in, you'll find yourself with slower reaction times and reduced perceptual and cognitive functions.

  • After a day or two of no sleep, the body loses its ability to properly metabolize glucose and the immune system stops working as well.

  • In some cases, three days of no sleep has led to hallucinations.

  • Care about how you look?

  • Studies have shown a direct correlation between sleep deprivation and a person's perceived beauty.

  • That is to say, sleep-deprived individuals appeared less healthy and less attractive than when they were well-rested.

  • The longest scientifically documented case of being awake was 264 hours or eleven days.

  • And while they did develop problems with concentration, perception, and irritability, the surprising truth is that they suffered no serious long-term health effects.

  • In fact, no individuals under these documented conditions experienced medical, physiological, neurological, or psychiatric problems.

  • But there are limited studies and this doesn't mean permanent damage couldn't be inflicted with more time.

  • Sleep deprivation experiments on rats, for example, generally lead to death after about two weeks.

  • But scientists aren't totally sure if they're dying from the lack of sleep or from the stress of constantly being woken up.

  • Perhaps we should look at Fatal Familial Insomnia for an answer:

  • A rare genetic disease of the brain which causes progressively worsening insomnia, or sleeplessness, leading to hallucinations, dementia, and ultimately death.

  • This disease has only affected around 100 people in the world, but their average survival span was around eighteen months.

  • Over time, the lack of sleep becomes worse and the body's organs begin to shut down.

  • So, while lack of sleep won't necessarily kill you quickly, continual sleep deprivation will have a negative effect on your body.

  • Sleep tight! But not too much.

  • Got a burning question you want answered? Ask it in the comments or on Facebook and Twitter.

  • And if you can't get enough science in your life, check out the Science Alert Facebook page, which is one of the best out there to keep you up-to-date and entertained with the latest news and breakthroughs.

  • And subscribe to ASAP Science for more weekly Science videos.

Ah, sleep!

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