Background and objectives

Fatigue is an adaptive state after prolonged effort and often goes hand in hand with changes in behavior and motivation, such as the urge to stop exerting further effort. However, fatigue may become chronic in nature, as seen in multiple psychiatric disorders and chronic diseases, thereby losing its adaptive function. The etiology of fatigue symptoms remains poorly understood. We aimed to investigate whether nocebo information about the fatigue inducing nature of a cognitive task may contribute to the experience of fatigue and the motivational urge to stop.

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.

中文翻译：

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反安慰剂信息对疲劳和停止冲动的影响：一项实验调查

背景和目标

疲劳是长时间努力后的一种适应性状态，通常与行为和动机的变化密切相关，例如停止进一步努力的冲动。然而，疲劳在本质上可能会变成慢性，如多种精神疾病和慢性疾病，从而失去其适应功能。疲劳症状的病因仍然知之甚少。我们旨在调查关于认知任务的疲劳诱导性质的反安慰剂信息是否可能导致疲劳体验和停止的动机冲动。

方法

参与者 ( N  = 46) 在进行认知努力（工作记忆任务）时反复评估当前经历的疲劳。至关重要的是，一半的参与者在此任务之前收到了 nocebo 指令，而另一半只收到了中性信息。

结果

在整个样本中，结果显示随着任务的进行，疲劳和停止的冲动增加。至关重要的是，相对于中性条件的参与者，反安慰剂条件的参与者报告说，在整个任务中停止的冲动更高。没有发现对疲劳有显着影响。然而，有趣的是，在控制负面影响条件之间的基线差异后，条件*任务块交互作用对疲劳有显着影响。

限制

限制包括相对较短的实验协议和男性相对于女性参与者的代表性不足。

结论

这些发现表明，临床医生和治疗师需要提高对他们交流中潜在反安慰剂效应的认识。