While cognitive fatigue is experienced by up to 80% of individuals with traumatic brain injury (TBI), little is known about its neural underpinnings. We previously hypothesized that presentation of rewarding outcomes leads to cognitive fatigue reduction and activation of the striatum, a brain region shown to be associated with cognitive fatigue in clinical populations and processing of rewarding outcomes. We have demonstrated this in individuals with multiple sclerosis. Here, we tested this hypothesis in individuals with TBI. Twenty-one individuals with TBI and 24 healthy participants underwent functional magnetic resonance imaging. Participants performed a task during which they were presented with 1) the Outcome condition where they were exposed to monetary rewards, and 2) the No Outcome condition that served as the control condition and was not associated with monetary rewards. In accordance with our hypothesis, results showed that attainment of rewarding outcomes leads to cognitive fatigue reduction in individuals with TBI, as well as activation of the striatum. Specifically, we observed a significant group by condition interaction on fatigue scores driven by the TBI group reporting lower levels of fatigue after the Outcome condition. fMRI data revealed a significant main-effect of condition in regions previously implicated in outcome processing, while a significant group by condition interaction was observed in the left ventral striatum as revealed by a priori region of interest analysis. Results suggest that a salient motivator can significantly reduce fatigue and that outcome presentation leads to increased activation of the ventral striatum in TBI. These findings can inform the development of future non-pharmacological cognitive fatigue treatment methods and contribute to the growing body of evidence showing the association between cognitive fatigue and the striatum.

中文翻译：

---

奖励介绍可减少脑部外伤时的工作疲劳。

尽管多达80％的颅脑外伤（TBI）患者经历了认知疲劳，但对其神经基础知之甚少。我们以前假设奖励性结果的呈现会导致认知疲劳的减少和纹状体的激活，这是大脑区域与临床人群的认知疲劳和奖励性结果的处理有关。我们已经在多发性硬化症患者中证明了这一点。在这里，我们在TBI患者中检验了这一假设。21名TBI患者和24名健康参与者进行了功能磁共振成像。参与者执行了一项任务，并向他们展示1）结果条件，使他们有获得金钱奖励的机会，2）无结果条件作为控制条件，与金钱奖励无关。根据我们的假设，结果表明，获得奖励的结果可导致TBI患者认知疲劳的减轻以及纹状体的激活。具体而言，我们观察到由条件交互作用引起的显着分组，由TBI组驱动的疲劳评分在结果状态后报告了较低的疲劳水平。fMRI数据揭示了先前涉及结果处理的区域中疾病的显着主要影响，而如通过先验关注区域分析所揭示的，在左腹纹状体中观察到了显着的逐条件相互作用。结果表明，显着的诱因可以显着减轻疲劳，结果提示可导致TBI腹侧纹状体的激活增加。这些发现可以为将来的非药物性认知疲劳治疗方法的发展提供信息，并有助于越来越多的证据显示认知疲劳与纹状体之间的关联。