PHILADELPHIA (CBS) - There have been many studies that have been designed to look at bullies and how to prevent problems or determine the personality types prone to bullying and being bullied. But with growing scientific research and better technology we are getting improved looks at the brain.

A University of Chicago study is an example.

Researchers gave several bullies—teenage boys– functional magnetic resonance imaging brain scans while the boys watched a video clip of someone inflicting pain on another person; basically stepping on a foot. The brain scans revealed that boys with aggression problems tended to have activity in at least one of the reward centers of their brain.

This suggests they enjoyed the experience. In contrast, boys without aggression problems showed no brain activity at all.

Reported By Dr. Brian McDonough, KYW Newsradio Medical Editor