Title: Origins and consequences of cognitive fatigue

Speaker: Mathias Pessiglione (Paris Brain Institute (ICM), Pitié-Salpêtrière Hospital, Paris)

Location: In Person & Online via Zoom

Abstract: Computers can play chess continuously for as long as they are plugged. Why is the human brain susceptible to fatigue after just a few hours? Although it has been studied for more than a century, there is still no mature theory of cognitive fatigue. In this seminar, I will provide some behavioral and neuroimaging evidence that might cast light on the origins and consequences of cognitive fatigue, understood as an objective post-effect of cognitive control exertion on brain and behavioral activities. The origin would be the accumulation of potentially toxic by-products that increase the cost of recruiting the cognitive control brain system. The consequence would not necessarily be fatigue sensation or performance decline, which can be ignored or compensated, but a shift in cost-benefit tradeoffs that drive decision-making. When fatigued, people indeed avoid taking actions that involve cognitive control – instead, they go for immediate gratifications that can be obtained without investing time or effort. This decision bias, a reliable fatigue marker observed in healthy participants after a period of hard work, might be exacerbated in pathological conditions plagued with cognitive fatigue, such as burnout, depression and cancer.