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All of Those After-School Fights Lowered Your IQ

But only if you lost.
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Medical News Today, a repository of some of the weirdest medical research to still be legitimate, highlights a study by Florida State University criminologists on the neurological effects of teenage fisticuffs. It's not good.

We usually think about developmental fragility in terms of younger children and fetuses. Think of all of the ink spilled debating whether or not pregnant women should avoid alcohol, or what watching a violent movie in your living room does or doesn't do to your six-month-old baby, playing nearby.

Losing two IQ points for an adolescent is the equivalent of missing one year of school, in terms of both emotional maturity and reasoning ability.

As it turns out, adolescent brains are just as easy to dent. The FSU study found that kids who had gotten in fights rough enough to cause injury lost 1.64 IQ points on average for boys, and more than three points for girls. Injury occurs in about one in 20 schoolyard brawls, the study claimed.

That doesn't sound like much—I'm sure I lost an IQ point or two viewing Iron Man 3. But losing two IQ points for an adolescent is more serious. It's the equivalent of missing one year of school, in terms of both emotional maturity and reasoning ability, the study claimed.

The FSU research looked at 20,000 teens and followed them into adulthood. The large sample was available from the National Longitudinal Study of Adolescent Health, a data set created between 1994 and 2002 which periodically measured health, including psychological and neurological health, in a cohort of teens tracked well into adulthood.

One question the study didn't answer was whether only the injured party in a fight lost IQ points, or whether both did, from the emotional impact of scrapping. It seems like the former: When the criminologists controlled for head injuries specifically, the IQ loss got, as you might suspect, a lot worse.

But if that's so, then the study's message could be read two ways. The right way is "Kid's shouldn't fight." The other, unfortunately, is "If you get in a fight, make sure the other kid is the one who ends up in the nurse's office, not you." That's probably not the conclusion the researchers had hoped for.