Cognitive fatigue during testing: An examination of trait, time-on-task, and strategy influences

What are the consequences of testing over an extended period? We report a study of 4 hr of nearly continuous testing on two verbal tests (Cloze and Completion). Prior to the testing session, participants completed a series of nonability trait measures, including selected personality and motivation scales. During the study, participants (N = 99) were also administered a series of subjective fatigue and affect measures. We examined the effect of increasing time-on-task on performance and subjective fatigue, along with the relative influences of trait measures in predicting individual differences in subjective fatigue as time-on-task increased. In addition, we examined whether performance strategy differences were associated with either performance or subjective fatigue measures. Results indicated a dissociation between subjective fatigue (increasing over time-on-task) and performance measures (which were stable or showed slight improvements as time-on-task increased). Trait complexes accounted for significant amounts of variance in subjective fatigue and positive affect over the course of the test session. Performance strategies of overactivity, withdrawal, and mixed overactivity and withdrawal were identified, and correlates of the strategies were examined. Implications for analyzing performance strategies to evaluate reactions to cognitive fatigue, and the prediction of individual differences in cognitive fatigue during testing are discussed.