JOURNAL OF EXPERIMENTAL SOCIAL PSYCHOLOGY 3,41-46 (1967) Effect of Expectancy of Task Duration on the Experience of Fatigue’ BILL WALSTER University of Minnesota AND ELLIOT ARONSON University of Texas If a person is performing a fatiguing task and firmly expects that he must continue for a great length of time, feelings of extreme fatigue will have unpleasant consequences: Either he will termi- nate the task, or he will be miserable while completing it. Conse- quently, in order to avoid unpleasantness, people will suppress feelings of fatigue until their task is virtually complete, when they shouldexperience a sharpincrease in fatigue-since such feelings are no longer troublesome. In an experiment, subjects performed a series of fatiguing tasks. After a given number of tasks, those individualswho were led to believe that their chorewas virtually at an end reported a greater increase in fatigue than those who expected that they must continue for a longer period of time. The experience of fatigue is undoubtedly influenced by psychological as well as physical factors (e.g., Bartley and Chute, 1947). One important psychological factor determining a person’s feelings of fatigue might be the individual’s expectation concerning the amount of work that he has yet to do. If a person feels very fatigued while performing a task, and if it is important that he complete a task in a given period, the veridical perception of his own fatigue might have unpleasant consequences; i.e., he would either quit or be very unhappy while continuing. A person can avoid or reduce these unpleasant consequenceseither by “ignoring” his fatigue or by underestimating it. Consequently, if an individual is en- gaged in a task that he wishes to complete, he will avoid considering how tired he is until his task is very near completion. If feelings of fatigue do occur to an individual in spite of his avoidance of such conscious con- ‘This study was supported by National Science Foundation Grants GS 202and GS 750 to Elliot Aronson. 41