Researchers have spent a lot of time looking at the question of why some people are more aggressive than others. They have suggested that these people have different kinds of brains, suffer from cognitive impairment or immaturity, or possess a “warrior gene” that predisposes them to risky behavior. One psychologist, Michael Apter of Georgetown University, theorized that aggression is driven by the pursuit of a pleasure sensation that comes from seeing a rival’s fortunes reversed.
