Abstract
We have recently shown that mental fatigue leads to decreased visuomotor adaptation early in training and is associated with decreased engagement of explicit processes (i.e., conscious strategy). In the current research we asked if mental fatigue hinders the engagement of explicit contributions to visuomotor adaptation once they have been established. Participants (n = 20) trained to reach with distorted cursor feedback which was rotated 40° relative to hand motion. Explicit contributions were determined based on participants’ reach direction when they were instructed to reach while using any strategies they had developed during the rotated reach training trials. Following confirmation that participants had adapted their reaches and explicit processes were engaged, participants completed a mentally fatiguing task for 32 minutes. A self-report questionnaire confirmed that participants experienced mental fatigue following the fatiguing task. Furthermore, explicit adaptation assessed immediately after the fatiguing task indicated that participants were able to engage in explicit reaching strategies. This engagement in explicit adaptation was maintained at a similar level before and after the mentally fatiguing task (explicit adaptation pre-mentally fatiguing task: 22.1°; vs post-mentally fatiguing task: 23.3°; p = 0.768). Thus, while mental fatigue may interfere with one’s ability to develop explicit reaching strategies, the results of the current study suggest that mental fatigue does not impact the engagement of explicit strategies once they are established.
