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10 Horrible Things Pulling An All-Nighter Does To Your Brain

If HANGRY = hungry + angry, would that mean that SLANGRY = sleepy + angry? Asking for a friend.

You know the rules: Adults should get about seven or eight hours of sleep a night. EVERY NIGHT!

And teens need even more than that.

But sometimes that just... doesn't happen. Maybe you've got a big exam to study for.

Or maybe you're all about that party till the breaka-breaka dawn thing.

Or maybe you have a really bad read-the-internet-all-night-long issue.

Either way, pulling an all-nighter can do some funky and awful stuff to your brain. Like these 10 things:

1. You'll have trouble remembering anything you tried to learn during the day (or night).

2. You'll stay stuck on any complicated problems you can't figure out.

3. Your circadian rhythm will be thrown off, making you feel like absolute garbage.

4. Toxic metabolic refuse builds up in your brain.

5. Your brain legit stops functioning as well as it normally does.

6. Your judgment will go out the window.

7. So will your ability to process sensory information.

8. You'll be moody as all hell.

"After just one night of lost sleep, people have moodiness problems," Morgenthaler says. "They become crabby and not stable emotionally."

9. You could suffer from a "sleep attack," where your brain forces you to pass out in spite of your every intention not to — which can be deadly.

Throughout the day, as ATP molecules are used to burn energy, adenosine byproducts get left behind. As the adenosine levels build up, that sends a stronger and stronger signal to your brain that you need sleep. Once it hits critical mass, that can trigger a switch in your brain that forces you to fall asleep immediately and involuntarily. "It's almost like fainting, but it's an involuntary sleep attack," Czeisler says.

During a boring lecture, this isn't a big deal. But if you're driving a car, it just takes a few seconds to veer off the road or into oncoming traffic, killing yourself or others. "These types of accidents are much more likely to have a higher fatality rate than other types of accidents," Czeisler says. "If you're drunk, you're at least moving the steering wheel. But when you fall asleep, you don't take any evasive maneuvers and you just sail right into whatever you're about to hit."

10. You will drive like a drunk person.

Even if you don't fall asleep behind the wheel, you're still a danger to yourself and others after pulling an all-nighter. "If you've been awake for 24 hours, your performance is as impaired as if you were legally drunk and had a 0.1 BAC," Czeisler says.

And here's a fun fact:

"Chronic sleep deprivation is more dangerous" in a number of ways than not sleeping for a night or two, Morgenthaler says. More on that another day.

But first... nap time.

The longer you stay awake, the more you use up available ATP molecules for fuel. An earlier version of this article misstated that the molecules themselves get degraded into less complex sources of fuel.