International University of La Rioja (UNIR), Logroño, Spain.
University of Central Florida, Orlando, USA.
Hum Factors. 2019 Sep;61(6):906-919. doi: 10.1177/0018720818816436. Epub 2019 Jan 17.
Modeling and evaluating a series of power law descriptions for boundary conditions of undiminished cognitive capacities under thermal stress.
Thermal stress degrades cognition, but precisely which components are affected, and to what degree, has yet to be fully determined. With increasing global temperatures, this need is becoming urgent. Power-law distributions have proven their utility in describing differing natural mechanisms, including certain orders of human performance, but never as a rationalization of stress-altered states of attention.
From a survey of extant empirical data, absolute thresholds for thermal tolerance for varying forms of cognition were identified. These thresholds were then modeled using a rational power-law description. The implications of the veracity of that description were then identified and analyzed.
Cognitive performance thresholds under thermal stress are advanced as power-law relationships, t = f(T) = c[(T - T)/T]. Coherent scaling parameters for diverse cognitive functionalities are specified that are consistent with increases in deep (core) body temperature. Therefore, scale invariance provides a "universal constant," viz, 20% detriment in mental performance per 10% increase in T deviation, from a comfortable reference temperature T.
We know the thermal range within which humans can survive is quite narrow. The presented power-law descriptions imply that if making correct decisions is critical for our future existence, then our functional thermal limits could be much more restricted than previously thought.
We provide our present findings, such that others can both assess and mitigate the effects of adverse thermal loads on cognition, in whatever human scenario they occur.
建立并评估热应激下认知能力无损边界条件的一系列幂律描述模型。
热应激会降低认知能力，但具体哪些认知成分受到影响以及受影响的程度尚未完全确定。随着全球气温的升高，这种需求变得越来越迫切。幂律分布已被证明可用于描述不同的自然机制，包括某些人类行为的顺序，但从未作为注意力受应激改变状态的合理化依据。
通过对现有经验数据的调查，确定了不同形式认知的热耐受绝对阈值。然后使用合理的幂律描述对这些阈值进行建模。接着，确定并分析了该描述真实性的含义。
热应激下的认知表现阈值被提出为幂律关系，t = f（T）= c[（T - T）/T]。指定了各种认知功能的一致缩放参数，与深部（核心）体温升高一致。因此，标度不变性提供了一个“通用常数”，即每增加 10%的 T 偏差，心理表现就会降低 20%。
我们知道人类能够生存的热范围相当狭窄。所提出的幂律描述表明，如果正确决策对我们的未来生存至关重要，那么我们的功能热极限可能比之前认为的要严格得多。
我们提供了目前的发现，以便其他人可以评估和减轻任何人类场景中不利热负荷对认知的影响。
