EFFECT OF MENTAL FATIGUE ON SPEED–ACCURACY TRADE-OFF
V. ROZAND, * F. LEBON, C. PAPAXANTHIS AND R. LEPERS
The aim of this study was to investigate the effects of mental fatigue on the duration of actual and imagined
goal-directed arm movements involving speed–accuracy trade-off.
The present study demonstrated that mental fatigue induced by a prolonged cognitive task increased actual movement duration, while maintaining Fitts’ law. The increase in movement duration was also present for
imagined task, suggesting that proactive changes occurred during the preparatory state of the movement.
Our results attested that CNS adapted motor planning to preserve task success in presence of mental fatigue.
This finding provides better insights into the role of the brain in regulating performance with mental fatigue, as
previously suggested on endurance performance (Marcora et al., 2009). Although this study was performed on healthy subjects, the results may benefit to the comprehension of patients affected by chronic fatigue syndrome
that is associated with slowed psychomotor and/or processing speed (Marshall et al., 1996; Davey et al., 2001). Future neuroimaging studies could help understand the regulatory mechanisms of motor task performance in the presence of mental fatigue.