Mental fatigue is usually accompanied by drops in task performance and reduced willingness for further exertion. A value-based theoretical account may help to explain such negative effects. In this view, mental fatigue influences perceived costs and rewards of exerting effort. However, no formal mathematical framework has yet been proposed to model and quantitatively estimate the effects of mental fatigue on subjective evaluations of effort expenditure, under possibly imperfect self-perceptions of internal fatigue states. We proposed a mathematical framework to model human cognitive effort allocations, assuming mental fatigue states are partially observable with semi-Markov dynamics. We modeled effort allocation decisions as a means to the goal of maximizing cumulative subjective values over a given time horizon. We developed an estimation method to identify subjective values and the hidden dynamics of mental fatigue, which can in future work be applied to self-reports, psychophysiological indices, and behavioral outcomes associated with fatigue. The modeling and estimation method was tested using a simulated n-back task under a free-choice paradigm, with model parameters fine-tuned from past studies. The proposed approach was able to recapitulate task performance and task engagement patterns observed under mental fatigue. This work advances a reward/cost trade-off account for explaining the exertion of mental effort and suggests new avenues for both theoretically and empirically relevant understandings of how cognitive operations are affected by mental fatigue.

中文翻译：

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精神疲劳对努力分配的影响：建模和估计。

精神疲劳通常伴随着任务表现的下降和进一步努力的意愿降低。基于价值的理论解释可能有助于解释这种负面影响。从这个角度来看，精神疲劳会影响感知成本和付出努力的回报。然而，在内部疲劳状态可能不完美的自我感知下，尚未提出正式的数学框架来建模和定量估计精神疲劳对努力支出主观评估的影响。我们提出了一个数学框架来模拟人类认知努力分配，假设精神疲劳状态可以通过半马尔可夫动力学部分观察到。我们将努力分配决策建模为在给定时间范围内最大化累积主观价值目标的一种手段。我们开发了一种估计方法来识别主观价值和精神疲劳的隐藏动态，在未来的工作中可以应用于自我报告、心理生理指标和与疲劳相关的行为结果。使用模拟测试建模和估计方法自由选择范式下的n -back 任务，模型参数根据过去的研究进行了微调。所提出的方法能够概括在精神疲劳下观察到的任务绩效和任务参与模式。这项工作提出了一个奖励/成本权衡帐户来解释脑力劳动的消耗，并为从理论上和实证上相关的理解心理疲劳如何影响认知操作提出了新的途径。