What's the cause of bar fights? Well... in addition to alcohol

Peter Giancola & Michelle Corman of the University of Kentucky have determined why drunks at the bar get into fights. Here's how they did it and the pretty nifty results:

The scientists tested this idea on a group of young Kentucky men. Some of the men drank three to four screwdrivers before the experiment, while others stayed sober. Then they had them all compete against another person in a somewhat stressful game that required very quick responses. Every time they lost a round, they received a shock varying in intensity. Likewise, when they won a round they gave their opponent a shock. The idea was to see how alcohol affected the men's belligerence, as measured by the kinds of shocks they chose to hand out.

But there was more to it. Giancola and Corman also deliberately manipulated some of the volunteers' cognitive powers. They required them--some drinkers, some not--to simultaneously perform a difficult memory task. The idea was to see if they could distract those who were "under the influence" from their "hostile" situation. If they could tax their limited powers of concentration, perhaps they wouldn't process the fact that someone was zapping them with electricity.

And that's exactly what happened. As reported in the July issue of Psychological Science, the drunks who had nothing to distract them were predictably mean, exhibiting aggression towards their adversaries. However, the drunks whose attention was focused elsewhere were actually less aggressive than the sober non-drinkers. This seems counterintuitive at first, but it's really not: The sober men were cognitively intact, so they would naturally attend to both provocations and distractions in the room, resulting in some low level of aggression.

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So what's the moral of the story. Yes... force everyone to perform difficult memory tasks at the bar. No talking, no making out, no easy tasks like darts. Memorize random sequences of number and letters and it will be fun for all!