The influence of nocebo information on fatigue and urge to stop: An experimental investigation

Methods

Participants (N = 46) repeatedly rated currently experienced fatigue while engaging in cognitive effort (working memory task). Crucially, half of participants received nocebo instructions prior to this task, whereas the other half only received neutral information. Results: Over the entire sample, results showed an increase in fatigue and urge to stop as the task progressed.

Crucially, participants in the nocebo condition reported a higher urge to stop throughout the task relative to participants in the neutral condition. No significant effects were found for fatigue. Interestingly however, after controlling for baseline differences between conditions in negative affect, there was a significant Condition*Task block interaction effect on fatigue.

Limitations: Limitations include the relatively short experimental protocol and the underrepresentation of male relative to female participants. Conclusions: These findings suggest that heightened awareness among clinicians and therapists about potential nocebo effects in their communication is warranted.