Following the game, participants were placed inside an MRI machine and then saw their fellow players zapped with electricity. The activity in their brain was recorded as they watched.
The scans revealed changes in activity as players who had cooperated got zapped, compared with those who had double-crossed them in the game. The results suggest that men get a much bigger kick than women from seeing revenge physically exacted on someone perceived to have wronged them. (emphasis mine)
Click here for the whole thing.
Does this really surprise too many people? My experience is that men are much less likely to be forgiving of being crossed than women, and much more likely to enjoy seeing the people who crossed them get their comeuppance.
HT: Mahalanobis at The Alpha And Omega.