Framing effort: How expectation shapes the experience of mental fatigue

The way a task is presented can shape how effort is consciously appraised and, in turn, influence the subjective experience of mental fatigue. Despite widespread use of laboratory-based induction paradigms, the role of expectation and contextual framing in modulating awareness of effort remains underexplored. In a 3 × 3 between-subjects design, 108 participants completed one of three 10-min tasks (Stroop task, Mackworth Clock, or watching a documentary), each presented with either an easy/straightforward, fatiguing/challenging, or neutral instruction frame. Participants rated mental fatigue, task demand, and motivation post task. Analyses tested main and interaction effects of task and framing and whether motivation was associated with mental fatigue responses across conditions. Task type significantly influenced ratings, with the Stroop task evoking the highest mental fatigue. Instructional framing affected mental fatigue perception, with both the easy and fatiguing frames eliciting higher mental fatigue than neutral instructions. No Task × Framing interaction emerged. Self-reported motivation was associated with lower mental fatigue only in the video condition. Instructional framing influences the conscious experience of effort and mental fatigue, even when objective task demands remain constant. These findings suggest that mental fatigue arises from expectation-driven appraisal rather than a fixed outcome of cognitive load, highlighting the importance of contextual factors in shaping perceived mental fatigue. (PsycInfo Database Record (c) 2026 APA, all rights reserved).