Money Affects Theory of Mind Differently by Gender

Theory of Mind (ToM) - the ability to understand other's thoughts, intentions, and emotions - is important for navigating interpersonal relationships, avoiding conflict, and empathizing. Prior research has identified many factors that affect one's ToM ability, but little work has examined how different kinds of monetary incentives affect ToM ability. We ask: Does money affect ToM ability? If so, how does the effect depend on the structure of monetary incentives? How do the differences depend on gender? We hypothesize that money will affect ToM ability differently by gender: monetary rewards increase males' motivation to express ToM ability while simultaneously crowding out females' motivation. This prediction is confirmed in an experiment that varies the structure of monetary rewards for correct answers in the Reading the Mind in the Eyes Test (RMET). RMET scores decrease for females and increase for males with individual payments, and this effect is stronger with competitively-structured payments. RMET scores do not significantly change when monetary earnings go to a charity. Whether money improves or hinders ToM ability, and, hence, success in social interactions, thus depends on the interaction of gender and monetary incentive structure.