Ego depletion

Ego depletion refers to the idea that self-control or willpower is an exhaustible resource that can be used up. When that energy is low (rather than high), mental activity that requires self-control is impaired. In other words, using one's self-control impairs the ability to control one's self later on. In this sense, the idea of (limited) willpower is correct. In an illustrative experiment on ego depletion, participants who controlled themselves by trying not to laugh while watching a comedian did worse on a later task that required self-control compared to participants who did not have to control their laughter while watching the video.

Much of the early research on ego depletion was performed by Roy Baumeister, Mark Muraven, and their colleagues. In a recent series of studies, they suggest that a positive mood stimulus could help restore the depleted energy. They report on four studies where the positive mood stimulus was a surprise gift or short clips of stand-up comedy by Robin Williams and Eddie Murphy. They do not claim a general benefit in positive affect, i.e, benefit to people who had not previously engaged in self-regulatory tasks, rather the positive stimulus restores the capacity to self-regulate. The work is experimental and does not consider in depth the mechanisms by which performance is restored, whether it is because of an actual restoration of self-regulatory resources or provides an additional motivation to press on with a depleted self remains an open question.