The original idea
Roy Baumeister and colleagues proposed that self-control works something like a muscle that tires. In their early studies, people who resisted a tempting food gave up sooner on a later difficult puzzle. Hundreds of studies followed, using many pairs of tasks.
The replication problem
Re-analysis of the literature suggested that published effects were inflated by selective reporting. A preregistered multilab replication then found an effect close to zero. A further large project led by proponents reported at most a very small effect. Claims that glucose restores self-control have also fared poorly.
Where this leaves the idea
Few researchers now accept the original limited-resource account in its strong form. Alternatives suggest that after effort people shift their motivation and attention toward rewarding activities, or that beliefs about willpower shape the effect. Fatigue after long, demanding work is real, but a reliable depletion effect from brief laboratory tasks has not been established.
Further reading
- Baumeister, R. F., Bratslavsky, E., Muraven, M., & Tice, D. M. (1998). Ego depletion: Is the active self a limited resource? Journal of Personality and Social Psychology, 74, 1252-1265.
- Hagger, M. S., et al. (2016). A multilab preregistered replication of the ego-depletion effect. Perspectives on Psychological Science, 11, 546-573.
- Vohs, K. D., et al. (2021). A multisite preregistered paradigmatic test of the ego-depletion effect. Psychological Science, 32, 1566-1581.