Department of Behavioural Neuroscience, Institute of Normal and Pathological Physiology, Centre of Experimental Medicine, Slovak Academy of Sciences, Sienkiewiczova 1, 813 71 Bratislava, Slovakia.
Department of Behavioural Neuroscience, Institute of Normal and Pathological Physiology, Centre of Experimental Medicine, Slovak Academy of Sciences, Sienkiewiczova 1, 813 71 Bratislava, Slovakia; Social, Cognitive and Affective Neuroscience Unit, Institute of Basic Psychological Research and Research Methods, Faculty of Psychology, University of Vienna, Liebiggasse 5 A-1010, Vienna, Austria.
Cognition. 2018 May;174:94-102. doi: 10.1016/j.cognition.2018.02.004. Epub 2018 Feb 12.
Cognitive flexibility emerges from an interplay of multiple cognitive systems, of which lexical-semantic and executive are thought to be the most important. Yet this has not been addressed by previous studies demonstrating that such forms of flexible thought deteriorate under stress. Motivated by these shortcomings, the present study evaluated several candidate mechanisms implied to mediate the impairing effects of stress on flexible thinking. Fifty-seven healthy adults were randomly assigned to psychosocial stress or control condition while assessed for performance on cognitive flexibility, working memory capacity, semantic fluency, and self-reported cognitive interference. Stress response was indicated by changes in skin conductance, hearth rate, and state anxiety. Our analyses showed that acute stress impaired cognitive flexibility via a concomitant increase in sympathetic arousal, while this mediator was positively associated with semantic fluency. Stress also decreased working memory capacity, which was partially mediated by elevated cognitive interference, but neither of these two measures were associated with cognitive flexibility or sympathetic arousal. Following these findings, we conclude that acute stress impairs cognitive flexibility via sympathetic arousal that modulates lexical-semantic and associative processes. In particular, the results indicate that stress-level of sympathetic activation may restrict the accessibility and integration of remote associates and bias the response competition towards prepotent and dominant ideas. Importantly, our results indicate that stress-induced impairments of cognitive flexibility and executive functions are mediated by distinct neurocognitive mechanisms.
认知灵活性源于多个认知系统的相互作用，其中词汇语义和执行被认为是最重要的。然而，之前的研究表明，这种灵活思维的形式在压力下会恶化，这些研究并没有解决这个问题。受这些缺点的启发，本研究评估了几种被认为可以调节压力对灵活思维的损害作用的候选机制。57 名健康成年人被随机分配到心理社会应激或对照条件下，同时评估他们在认知灵活性、工作记忆容量、语义流畅性和自我报告的认知干扰方面的表现。应激反应通过皮肤电导、心率和状态焦虑的变化来表示。我们的分析表明，急性应激通过交感神经兴奋的同时增加来损害认知灵活性，而这种中介物与语义流畅性呈正相关。应激还降低了工作记忆容量，这部分是由认知干扰的升高介导的，但这两个测量指标都与认知灵活性或交感神经兴奋无关。根据这些发现，我们得出结论，急性应激通过调节词汇语义和联想过程的交感神经兴奋来损害认知灵活性。特别是，研究结果表明，应激水平的交感神经激活可能会限制远程联想的可及性和整合，并使反应竞争偏向优势和主导思想。重要的是，我们的结果表明，认知灵活性和执行功能的应激诱导损伤是由不同的神经认知机制介导的。
