Active or Passive? Investigating Different Types of Cognitive Fatigue

Research in cognitive fatigue has identified the negative impact that cognitive exertion can have on subsequent task performance. An underexamined question is whether there are different types of fatigue, particularly: active fatigue, similar to cognitive fatigue, and passive fatigue, similar to boredom. This online study examined whether active and passive fatigue can be elicited and differentiated using computerized cognitive tasks. We compared subjective and behavioural outcomes to look for distinctions between fatigue types in response to different cognitive tasks. A sample of 122 participants (53% male; age 30.04 +/- 3.50 years) rated their subjective state before and after one of three 8-min cognitive task conditions (TloadDback, Mackworth Clock, Documentary/Control). Next, participants also completed a second cognitive task (Flanker task). The task expected to be actively fatiguing (TloadDback) was rated the most difficult, effortful, and mentally and temporally demanding. The task expected to be passively fatiguing (Mackworth Clock) had the greatest increases in subjective fatigue, boredom, and sleepiness, and the greatest decrease in "want-to" motivation. There were no differences between conditions for Flanker performance. We showed that different fatigue types could be elicited using different computerized cognitive tasks. The passively fatiguing task had the most negative influence on subjective fatigue and motivation, suggesting a nonengaging or "boringly fatiguing" task induces a more detrimental type of fatigue. A key next step is to examine longer cognitive tasks to determine whether effects from different fatigue types become more prominent with time-on-task.