Don't Blame Me... My Brain's the Asshole
Link

Researchers from the University of Chicago...wanted to learn whether the brain of an aggressive youth responds differently to violence than the brain of someone who is not a bully. In a chilling finding, the researchers found aggressive youths appear to enjoy inflicting pain on others.
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When the aggressive youths watched people intentionally inflicting pain on another, the scan showed a response in the part of the brain associated with reward and pleasure. The youths who were not aggressive didn’t show the same brain response. The study, published in the current issue of the journal Biological Psychology, suggests that the brain’s natural impulse for empathy may be disrupted in the brain of a bully, leading to increased aggression.

I wonder if there is some basis for the assumption that "the brain's natural impulse" is "for empathy". Doesn't it seem just as likely that the development of empathy disrupts the brain's natural impulse for aggression, instead of the other way around? (and which would be better news, by the way?) Is that just a telling bias here, or do we really have a reason to believe that empathy is the "natural" state?

Beyond that, is this even news? Did we really think the world's bullies are reluctant aggressors? Of course they enjoy it, and of course that enjoyment (like all emotional response) shows up somewhere in the brain. The bigger questions are: At what age does it first register as enjoyment? Did cultural/social behavior nurse the growth of this neural pathway (or whatever it is)? Behavior that could be avoided? How prevalent is this response? Do a high percentage of males share this reaction but have simply learned to curb their actions to suppress it?

If you're interested you can read the study here.(pdf) It might have the answers to some of my questions but it's written in science, so it's hard for me to make heads or tails of it, at least with just a scan.