In this study, we examined the cognitive performance of subtropically acclimatized subjects at an extreme high indoor temperature and the effect of decreased humidity on the cognitive performance at the high temperature. Forty‐eight healthy subjects experienced the three exposure conditions: 26°C/relative humidity (RH) 70%, 39°C/RH50%, and 39°C/RH70% in a climate chamber. During 140‐minute‐long exposures to each thermal condition, they were required to perform cognitive tests that assess the perception, spatial orientation, concentration, memory, and thinking abilities. Meanwhile, their heart rate, core temperature, skin temperature, blood pressure, and body weight were measured and subjective responses, that is, thermal comfort, perceived air quality, and acute health symptoms were investigated. At the relative humidity of 70%, increasing indoor temperature from 26°C to 39°C caused a significant decrease in the accuracy of these cognitive tests. However, when the relative humidity decreased from 70% to 50% at 39°C, the accuracy of the cognitive tests increased significantly. Accordingly, the physiological and subjective responses of the subjects changed significantly with the changes in indoor temperature and humidity, which provided a basis to the variation in the cognitive performance. These results indicated that decreasing indoor humidity at extreme high temperature could improve the impaired cognitive performance.

中文翻译：

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降低湿度可提高室内极高温度下的认知能力

在这项研究中，我们检查了亚热带气候适应对象在极高室内温度下的认知表现，以及湿度降低对高温下认知表现的影响。48 名健康受试者在气候室中经历了三种暴露条件：26°C/相对湿度 (RH) 70%、39°C/RH50% 和 39°C/RH70%。在 140 分钟长的暴露于每种热条件下的过程中，他们被要求进行认知测试，以评估感知、空间定向、注意力、记忆力和思维能力。同时，测量他们的心率、核心温度、皮肤温度、血压和体重，并调查主观反应，即热舒适度、感知空气质量和急性健康症状。在 70% 的相对湿度下，将室内温度从 26°C 增加到 39°C 会导致这些认知测试的准确性显着下降。然而，当相对湿度从 70% 降至 39°C 时的 50% 时，认知测试的准确性显着提高。因此，受试者的生理和主观反应随着室内温度和湿度的变化而发生显着变化，这为认知表现的变化提供了依据。这些结果表明，在极端高温下降低室内湿度可以改善受损的认知能力。被试的生理和主观反应随着室内温度和湿度的变化发生显着变化，这为认知表现的变化提供了依据。这些结果表明，在极端高温下降低室内湿度可以改善受损的认知能力。被试的生理和主观反应随着室内温度和湿度的变化发生显着变化，这为认知表现的变化提供了依据。这些结果表明，在极端高温下降低室内湿度可以改善受损的认知能力。