Public Health and Sport Sciences, University of Exeter, St Luke's Campus, Heavitree Road, Exeter, EX1 2LT, UK.
Behav Res Methods. 2024 Apr;56(4):3995-4008. doi: 10.3758/s13428-023-02191-5. Epub 2023 Aug 3.
Mental fatigue is a commonplace human experience which is the focus of a growing body of research. Whilst researchers in numerous disciplines have attempted to uncover the origins, nature, and effects of mental fatigue, the literature is marked by many contradictory findings. We identified two major methodological problems for mental fatigue research. First, researchers rarely use objective measures of mental fatigue. Instead, they rely heavily on subjective reports as evidence that mental fatigue has been induced in participants. We aimed to develop a task which led to not only a subjective increase in mental fatigue, but a corresponding performance decrement in the mentally fatiguing task as an objective measure. Secondly, current mental fatigue paradigms have low ecological validity - in most prior studies participants have been fatigued with a single repetitive task such as the n-back or Stroop. To move towards a more ecologically valid paradigm, our participants undertook a battery of diverse cognitive tasks designed to challenge different aspects of executive function. The AX-CPT, n-back, mental rotation, and visual search tasks were chosen to challenge response inhibition, working memory, spatial reasoning, and attention. We report results from 45 participants aged 19 to 63 years who completed a two-hour battery comprising four different cognitive tasks. Subjective fatigue ratings and task performance were measured at the beginning and end of the battery. Our novel method resulted in an increase in subjective ratings of fatigue (p < 0.001) and a reduction in task performance (p = 0.008). Future research into mental fatigue may benefit from using this task battery.
精神疲劳是一种常见的人类体验，也是越来越多研究的焦点。虽然许多学科的研究人员都试图揭示精神疲劳的起源、本质和影响，但该领域的文献存在许多相互矛盾的发现。我们确定了精神疲劳研究中的两个主要方法学问题。首先，研究人员很少使用精神疲劳的客观测量方法。相反，他们主要依赖主观报告来证明参与者已经产生了精神疲劳。我们旨在开发一种不仅会导致主观上的精神疲劳增加，而且会导致精神疲劳任务的相应表现下降的任务，作为客观测量的方法。其次，当前的精神疲劳范式的生态效度较低 - 在大多数先前的研究中，参与者都是通过单一的重复任务（例如 n-back 或 Stroop）来疲劳。为了向更具生态效度的范式转变，我们的参与者完成了一系列不同的认知任务，旨在挑战执行功能的不同方面。AX-CPT、n-back、心理旋转和视觉搜索任务被选择来挑战反应抑制、工作记忆、空间推理和注意力。我们报告了 45 名年龄在 19 岁至 63 岁之间的参与者的结果，他们完成了一个由四个不同认知任务组成的两个小时的电池。在电池的开始和结束时测量主观疲劳评分和任务表现。我们的新方法导致主观疲劳评分增加（p<0.001）和任务表现下降（p=0.008）。未来对精神疲劳的研究可能受益于使用这种任务电池。
