The effects of extreme high indoor temperature on EEG during a low intensity activity

Abstract

Climate warming has led to extreme high indoor temperatures above 39 °C in hot and humid areas during the summer, which poses a great risk to work safety. Cognitive impairment is considered to be one of the main causes of work safety accidents under high temperatures. However, there is still no sufficient physiological basis for the damage of high temperature to cognitive performance. EEG is a potential physiological indicator that reflects cognitive performance. Nevertheless, no relevant research on the effects of extreme high indoor temperatures exceeding 35 °C on EEG has been found. In this study, a climate chamber simulation experiment was conducted, and the neutral temperature was set at 26 °C and the extreme high indoor temperature at 39 °C. In the experiment, the subjects completed 6 cognitive tests in the sitting position, and the EEG signals of 14 channels were continuously collected during 25–60 min of the experiment. Based on the analysis of the power of the EEG signals, the effects of extreme high indoor temperature on EEG are investigated in this study. The results showed that, on the one hand, the EEG relative power of δ-band of whole brain increased significantly at 39 °C, while the EEG relative power of β-band of whole brain decreased significantly during certain experimental periods. On the other hand, the accuracy of Overlapping test also decreased significantly at 39 °C. This indicates that the change of δ-band and β-band of EEG signals provides a theoretical basis for the damage of extreme high temperature to cognitive performance from viewpoint of physiology.