Naughty or Nice? A Brain Chemical May Tell

Naughty or Nice? A Brain Chemical May Tell

Chemicals in your body can influence how generous or selfish you are, and, in recent years, experiments have explored the role of one called oxytocin — which one researcher calls the “moral molecule.” In an experiment known as the ultimatum game, one of two people is given a sum of money, say $100, and told he must decide how to split it with person No. 2. If person No. 2 is dissatisfied with the split, then she can reject it, but then the money vanishes, and neither person gets any.

Neuroeconomist Paul Zak and colleagues have performed many variations on this experiment. In one, they gave some participants a squirt of oxytocin to the nose beforehand, and found that the share of money they offered the other side increased by 80%. Zak’s work indicates oxytocin — once best known as a hormone released during birth and breast-feeding — also plays a fundamental role in promoting social behavior, he told an audience at the New York Academy of Sciences.