Bastien BLAIN (Institut du Cerveau et de la Moelle Epinière, Paris) donnera une conférence le 28 juillet sur la fatigue exécutive et la prise de décision.
Cet événement (invitation 
) se tiendra à l'UCL dans la salle "Centre Faculté 3" (Bibliothèque, RDC), à 17 heures, sur le campus de Louvain-en-Woluwe.
Abstract : While we understand quite well why muscles ache after prolonged exercise, the origins of mental fatigue still appear totally mysterious. Existing theories remain at a psychological level, with scarce supporting evidence. In a first study, we have showed that performing hard cognitive tasks (N = 27) for hours (>6 hours) induced an increase in the proportion of immediate reward chosen (impulsivity) over a higher delayed reward (intertemporal choice) more than while performing easy versions of the same tasks or playing video-games (N=26). At the neural level, a particular brain area in the LPFC, which was involved both in hard cognitive tasks and choice, decreased with time and mediated this effect. We then applied this paradigm to show that cognitive fatigue also arose while medical students (N = 52) rehearsed their lessons for hours before their examination. Impulsivity increased with time on tasks and was not related to subjective fatigue, hunger, or stress. At the computational level, this effect was due to an increase in a bias toward the immediate reward instead of the delay discounting rate. We finally applied this measure to study burnout syndrome of athletes following overtraining. An 50% overload of training (N = 19) increased choice impulsivity and decreased LPFC activity compared to a control group (n = 18). Altogether, these results support a concept of executive fatigue assuming that fatigue arises from the prolonged use (hours or weeks) of a system involved in executive control and is observable in decision making but not during executive tasks.
Contact : Dr. Alexandre ZENON (alexandre.zenon@uclouvain.be)