Ego Depletion - Key Experimental Evidence

Key Experimental Evidence

Roy Baumeister and his colleagues proposed a model that relates self-control to a muscle, which can become both strengthened and fatigued. Initial use of the “muscle” of self-control will cause a decrease in strength, or ego depletion, for subsequent tasks. Various experimental findings support this muscle model of self-control and ego depletion.

A key experiment by Roy Baumeister, Ellen Bratslavsky, Mark Muraven and Dianne Tice in 1998, demonstrated some of the first evidence that ego depletion has effects in many 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. Interestingly, this effect was not nearly as strong when individuals were not given a choice and were "forced" to write a counter-attitudinal speech. Thus, it is believed 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 is not 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.