Abstract

Human cognition unfolds in a multitude of environments, including those that are associated with extreme stressors. Successfully measuring and modeling behaviors in such environments is inherently difficult. The current effort aimed to assess variation in stability and flexibility of cognitive performance during cold stress, individual differences in errors, and physiological correlates. Fifty-seven service members completed cold water immersion during winter months. Individuals were required to immerse themselves in an outdoor pond for 10 minutes, reclothe into dry clothing, and attempt to rewarm. Simple reaction time and match-to-sample tasks were completed throughout the 90 minute procedure. To assess response stability, sample entropy was computed for the response time time-series of each task. Hierarchical clustering applied to sample entropy values identified two clusters of individuals. One highly affected group demonstrated low stability and weak flexibility by way of higher autocorrelation and more omission errors, and had lower hand temperature pre- and post-immersion. Results are discussed within the context of cold stress, adaptive behaviors, and cold stress.

摘要

人类认知在多种环境中展开，包括与极端压力源相关的环境。在这样的环境中成功地测量和建模行为本质上是困难的。目前的努力旨在评估冷应激期间认知表现的稳定性和灵活性的变化、错误的个体差异和生理相关性。五十七名服役人员在冬季完成了冷水浸泡。个人被要求在室外池塘中浸泡 10 分钟，重新穿上干衣服，并尝试重新加热。在整个 90 分钟的过程中完成了简单的反应时间和样品匹配任务。为了评估响应稳定性，计算每个任务的响应时间序列的样本熵。应用于样本熵值的层次聚类确定了两个个体集群。一个高度受影响的组通过更高的自相关性和更多的遗漏错误表现出低稳定性和弱灵活性，并且在浸泡前后手部温度较低。结果在冷应激、适应性行为和冷应激的背景下进行了讨论。