Román Cristina A F, DeLuca John, Yao Bing, Genova Helen M, Wylie Glenn R
Rocco Ortenzio Neuroimaging Center, Kessler Foundation, West Orange, NJ, United States.
Department of Physical Medicine and Rehabilitation, Rutgers University, Newark, NJ, United States.
Front Behav Neurosci. 2022 Mar 16;16:828566. doi: 10.3389/fnbeh.2022.828566. eCollection 2022.
Multiple Sclerosis (MS) affects 2.8 million persons worldwide. One of the most persistent, pervasive, and debilitating symptoms of MS is cognitive fatigue. While this has been known for over a century, cognitive fatigue has been difficult to study because patients' subjective (self-reported) cognitive fatigue has consistently failed to correlate with more objective measures, such as reaction time (RT) and accuracy. Here, we investigated whether more nuanced metrics of performance, specifically the metrics of Signal Detection Theory (SDT), would show a relationship to cognitive fatigue even if RT and accuracy did not. We also measured brain activation to see whether SDT metrics were related to activation in brain areas that have been shown to be sensitive to cognitive fatigue. Fifty participants (30 MS, 20 controls) took part in this study and cognitive fatigue was induced using four blocks of a demanding working memory paradigm. Participants reported their fatigue before and after each block, and their performance was used to calculate SDT metrics (Perceptual Certainty and Criterion) and RT and accuracy. The results showed that the SDT metric of Criterion (i.e., response bias) was positively correlated with subjective cognitive fatigue. Moreover, the activation in brain areas previously shown to be related to cognitive fatigue, such as the striatum, was also related to Criterion. These results suggest that the metrics of SDT may represent a novel tool with which to study cognitive fatigue in MS and other neurological populations. These results hold promise for characterizing cognitive fatigue in MS and developing effective interventions in the future.
多发性硬化症（MS）在全球影响着280万人。MS最持久、普遍且使人衰弱的症状之一是认知疲劳。尽管这一情况已为人所知超过一个世纪，但认知疲劳一直难以研究，因为患者主观（自我报告）的认知疲劳始终未能与更客观的指标，如反应时间（RT）和准确性相关联。在此，我们研究了更细微的表现指标，特别是信号检测理论（SDT）的指标，即便RT和准确性未显示出相关性，这些指标是否会与认知疲劳存在关联。我们还测量了大脑激活情况，以查看SDT指标是否与已被证明对认知疲劳敏感的脑区激活有关。五十名参与者（30名MS患者，20名对照者）参与了这项研究，通过四个要求较高的工作记忆范式块诱导产生认知疲劳。参与者在每个块前后报告他们的疲劳程度，并利用他们的表现来计算SDT指标（感知确定性和标准）以及RT和准确性。结果表明，标准的SDT指标（即反应偏差）与主观认知疲劳呈正相关。此外，先前已表明与认知疲劳相关的脑区，如纹状体的激活，也与标准相关。这些结果表明，SDT指标可能代表了一种研究MS和其他神经人群认知疲劳的新工具。这些结果为在MS中表征认知疲劳以及未来开发有效的干预措施带来了希望。
