The Effects of Cetelopram on Empathy

When you lower people's serotonin levels, when they're in the role of responder, they're more likely to reject offers they think are unfair. And conversely, when you boost serotonin levels, this makes them less likely to reject unfair offers. So there seems to be this link between having a low serotonin state and being unwilling to let people get away with the things that are perceived as unfair.