L'effet de la fatigue mentale sur la performance cognitive au cours de la vie adulte

peer reviewedBackground and aim. Cognitive aging models propose that cognitive resources available decrease with age, and that older people experience a more pronounced decline in performance over time. Mental fatigue is also known to negatively impact cognitive performance. How available cognitive resources interact with fatigue level across the lifespan remains largely unexplored. Our objective is to identify and compare the effects of an induced mental fatigue state on cognitive performance in young, middle-aged, and older participants. Methods. 43 young, 25 middle-aged and 19 older people performed a 32-min mental fatigue induction task in condition of high or low cognitive load (HCL/LCL). Cognitive load was modulated by the stimuli time duration (STD), with shorter STD leading to higher cognitive load, and thus, higher mental fatigue across task. A repeated measure ANOVA (p<0.05) was conducted to determine the effects of group (young, middle-aged, older), condition (HCL vs. LCL) and time on task (4 blocks of 8 min) on accuracy performance. Results. We observed main effects of group ((F(2,80)=7.31, p=.001), condition (F(1,80)=128.02, p<.001), block (F(3,185)=26.49, p<.001), and a condition by block interaction (F(3,240)=3.09, p=.04). Bonferroni post-hoc (p