Sleep deprivation makes you behave like an asshole, film at 11.

When you stay up half the night acting like a raging workaholic, apparently that makes your brain all funny:

In a forthcoming paper in the Academy of Management Journal, highlighted recently in the Financial Times, Michael Christian of the University of North Carolina’s Kenan-Flagler Business School and Aleksander Ellis of the University of Arizona’s Eller College of Management studied sleep-deprived nurses and students who’d pulled all-nighters in a sleep lab. They found that a lack of sleep led not just to poor performance on tasks that require “innovative thinking, risk analysis, and strategic planning”—though studies have shown all those to be true—but also to increased deviant and unethical behavior in both groups. Examples included rudeness, inappropriate responses and attempts to take more money than they’d earned.

Right. So, if I’m curt, tactless or otherwise less than pleasant with you these days, it’s probably because I was up late following my editor’s instructions and my prefrontal cortex isn’t up to snuff. Well, that and I was never really gifted in the finer points of small talk and cheeriness, anyway.

(As long as I’m on the subject of good manners: this is a friendly reminder that you are not entitled to stand next to your friend on the escalator. Stand to the right, walk to the left. The Metro is filled to bursting with sleep-deprived Washingtonians trying to get to work on time, and we’re not known for being all sunshine and light.)