The next time you wake up smelling like a bar tray and feeling like you've spent the previous several hours inside the spin cycle of a washing machine, blame your brain.
You knew what would happen when you started taking tequila shots at 10 pm; it's happened before. You know what a hangover feels like; it sucks. Yet you insist on staying on Drinky Time Highway until you're well past the Hangover exit. According to researchers at the University of Washington, this happens for a couple of reasons.
First, something called "positive memory bias" causes you to remember what you did while under the influence as much more awesome than it actually was. Like that time you danced on your friend's card table and broke it, or that time you almost got into a fight with that guy who told you that your favorite team sucks. Or that time you and your best friend spent over an hour trying to get a cab home on New Year's Eve and eventually just flagged some random guy in a car down and got in his backseat before he could object and made him drive you back to your house.
Secondly, cognitive dissonance can be blamed for our continuing to occasionally binge in spite of negative behaviors the activity brings out. We have a certain unflappable perception of who we are and how we act, and thus when we deviate from the self-dom we've established for ourselves, we justify our behavior by chalking it up to an anomaly. So, yes, you may have propositioned your friend's cousin who you know has a girlfriend, but you're not the type to do that. As Jamie Foxxxxxxxx (I forget how many x's he uses in his name; better safe than sorry) would say, you blame it on the a-a-a-a-a-alcohol.
Basically, your brain does a bunch of gymnastics moves to convince you in retrospect that the fun times were way more fun than they really were, the bad times weren't really so bad, and that how you act when you're drunk isn't your fault. Put them in a cocktail shaker, pour it over some ice, and you've got yourself a bad decision repeated over and over and over again; for some people, almost every weekend for the better part of a decade.
And this is why you can't get out of bed today, Drunkenstein. You'll never learn!