To cope with ever-increasing work demands, people often turn to multitasking. Although it is known that multitasking harms objective task performance, we know relatively little about how multitasking influences subjective experience. In this article, we develop hypotheses about the subjective experience of multitasking. Namely, we hypothesize that people multitask more often in the presence of challenge stressors (like workload, responsibility, and time pressure), that multitasking is one of the reasons why challenge stressors produce feelings of mental fatigue, and that multitasking feels especially mentally fatiguing for people with fewer cognitive resources—as people with fewer cognitive resources paradoxically must use particularly resource-demanding self-regulation processes to multitask. Using an experience sampling design, in Study 1 (N = 248 participants; 5,191 responses), we find support for these hypotheses. Given the increasing prevalence of multitasking, we then ask what can be done to reduce its negative consequences. Drawing on recent findings that mindfulness training increases the efficacy of self-regulation, we hypothesize that mindfulness training will compensate for cognitive resources by empowering people with fewer cognitive resources to multitask without feeling mentally fatigued. Pairing experience sampling with a long-term mindfulness training, in Study 2 (N = 114 participants; 1,197 responses), we replicate our initial findings and extend them: multitasking feels mentally fatiguing for people with fewer cognitive resources in the control condition but not in the mindfulness training condition. Taken together, these findings shed new light on the interface of work design, self-regulation, and mental fatigue.
