Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China.
Department of Occupational Therapy, Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Alberta, Canada; Rotman Research Institute, Baycrest Center for Geriatric Care, Toronto, Ontario, Canada.
Int J Psychophysiol. 2020 Apr;150:20-28. doi: 10.1016/j.ijpsycho.2020.01.006. Epub 2020 Jan 24.
Exposure to stress has a variety of consequences on human behavior and cognition. Although widely investigated, the impact of stress on working memory remains inhomogeneous. Individual differences in neuroendocrine responsiveness, for example, cortisol responses, may be factors that explain previous inconsistent results. This study assessed the role of cortisol responsiveness in the effects of psychosocial stress on working memory. To examine working memory processes, we analyzed both behavioral performances such as accuracy, response time, the inverse efficiency score, and event-related potentials (ERPs), including N1, P2, and P3. A total of 67 male college students completed a numerical 2-back task after being exposed to the Trier Social Stress Task (TSST) or a control task. The results showed shorter response time, better efficiency, and larger N1 and P2 amplitudes in the high-cortisol-responders compared to the low-cortisol-responders and the control group. This indicates a better working memory performance likely due to the enhancements in the orientation and mobilization of attention. Furthermore, a correlation analysis revealed a positive association between the cortisol change rate and the working memory performance and ERP data among the stressed individuals, suggesting that increased cortisol may facilitate working memory under acute psychosocial stress. These findings emphasize that the individual differences in cortisol responses may affect the impact of stress on working memory.
应激暴露对人类行为和认知有多种影响。尽管已经广泛研究，但应激对工作记忆的影响仍然不一致。例如，神经内分泌反应的个体差异，即皮质醇反应，可能是解释先前不一致结果的因素之一。本研究评估了皮质醇反应性在心理社会应激对工作记忆影响中的作用。为了研究工作记忆过程，我们分析了行为表现，如准确性、反应时间、逆效率得分和事件相关电位（ERP），包括 N1、P2 和 P3。共有 67 名男性大学生在完成 Trier 社会应激测试（TSST）或对照任务后完成了数字 2 背任务。结果表明，高皮质醇反应者的反应时间更短、效率更高、N1 和 P2 振幅更大，而低皮质醇反应者和对照组则相反。这表明由于注意力的定向和动员得到了增强，工作记忆表现更好。此外，相关分析显示，在应激个体中，皮质醇变化率与工作记忆表现和 ERP 数据之间呈正相关，表明急性心理社会应激下皮质醇的增加可能有助于工作记忆。这些发现强调了皮质醇反应的个体差异可能会影响应激对工作记忆的影响。
