Ego depletion

Ego depletion refers to the idea that self-control or willpower draw upon a limited pool of mental resources that can be used up. When the energy for mental activity is low, self-control is typically impaired, which would be considered a state of ego depletion. In particular, experiencing a state of ego depletion impairs the ability to control oneself later on. A depleting task requiring self-control can have a hindering effect on a subsequent self-control task, even if the tasks are seemingly unrelated. Self-control plays a valuable role in the functioning of the self on both individualistic and interpersonal levels. Ego depletion is therefore a critical topic in experimental psychology, specifically social psychology, because it is a mechanism that contributes to the understanding of the processes of human self-control. There have both been studies to support and to question the validity of ego-depletion as a theory.

The word "ego" in "ego depletion" is used in the "psychological" sense rather than the colloquial sense.

Some meta analyses and studies have questioned the size and existence of the ego depletion effect. The ultimate validity of those later studies are not universally agreed about.

American social psychologist Roy Baumeister and his colleagues proposed a model that described self-control like a muscle, which can become both strengthened and fatigued. The researches proposed that initial use of the “muscle” of self-control could cause a decrease in strength, or ego depletion, for subsequent tasks. Later experimental findings showed support for this muscle model of self-control and ego depletion.

A key experiment by Baumeister, Ellen Bratslavsky, Mark Muraven and Dianne Tice in 1998, demonstrated some of the first evidence that ego depletion had effects in diverse contexts or situations. They showed that people who initially resisted the temptation of chocolates were subsequently less able to persist on a difficult and frustrating puzzle task. They attributed this effect to ego depletion, which resulted from the prior resisting of a tempting treat. Additionally, it was demonstrated that when people voluntarily gave a speech that included beliefs contrary to their own, they were also less able to persist on the difficult puzzle, indicating a state of ego depletion. This effect was not nearly as strong when individuals were not given a choice and were "forced" to write a counter-attitudinal speech. Thus, they proposed that both the act of choice and counter-attitudinal behaviors draw upon the same pool of limited resources. While giving a counter-attitudinal speech is expected to produce ego depletion, introducing the element of choice further increases the level of experienced depletion. These findings demonstrated the effects of ego depletion in differential situations and emphasized that ego depletion may not be context-specific. This experiment was critical in that the researchers synthesized ideas proposed by prior studies that had suggested evidence for a strength model of willpower. With this study, Baumeister and his colleagues therefore provided the first direct experimental evidence of ego depletion, and initiated research interest on the subject.

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