Researchers at the University of Geneva developed an economic game in which a participant is challenged with the fair behavior of one player and the unfair aggravations of another player. They observed which areas were activated as the participant experienced injustice and anger. Then scientists gave the participant the chance to take revenge. For the first time, the role of DLPFC in revenge has been known and is separate from focused areas of anger in the amygdala and superior temporal lobe.