Ego Depletion Decreases Trust in Economic Decision Making

Three experiments tested the effects of ego depletion on economic decision-making in the investment game. Participants completed a self-control task or simplified version not requiring self-control. Then participants divided $10 between themselves and another person. The ostensible other person received triple the amount given and could return any portion to the participant. Giving less money, and therefore not trusting the other person, is the safe, self-interested response. Participants who had exerted self-control and were depleted gave the other person less money than those in the non-depletion condition (Experiment 1). This effect, however, was only observed among participants who were told they would never meet the other person. Amounts given did not differ for depleted and non-depleted participants who expected to eventually meet the other person (Experiment 2). Additionally, depletion did not cause decreased trust when participants believed they were interacting with a person very similar to themselves (Experiment 3). The implication is that self-control facilitates trust and enables people to override uncertainty in favor of socially constructive actions, especially when there are no other situational cues that motivate people to prioritize collective (versus individual) outcomes. The decrease in trust observed among depleted participants was strongest among neurotics.