A depleted mind feels inefficacious: Ego-depletion reduces self-efficacy to exert further self-control

Recent research has found that ego-depletion undermines self-control by motivating cognition that justifies conservation of mental resource. One potential cognitive mechanism is reduction of self-efficacy. Specifically, we propose that ego-depletion might demotivate self-control by making people believe that they are inefficacious in exerting self-control in subsequent tasks. Three experiments support the proposal. First, we demonstrated that (a) ego-depletion can reduce self-efficacy to exert further control (Experiments 1 to 3) and (b) the temporary reduction of self-efficacy mediates the effect of depletion on self-control performance (Experiment 2). Finally, we found that (c) these effects are only observed among participants who endorse a limited (versus non-limited) theory of willpower and are, hence, more motivated to conserve mental resources (Experiment 3). Taken together, the present findings show that decrease in self-efficacy to exert further self-control is an important cognitive process that explains how ego-depletion demotivates self-control. This research also contributes to the recent discussion of the psychological processes underlying ego-depletion.