Critical dynamic characteristics of brain activity in thermal comfort state

Thermal comfort is a crucial aspect of building design that can have a direct impact on people's health, productivity, and overall comfort. Evaluating indoor thermal comfort could be done through various methods, and this paper explored the feasibility of using electroencephalogram (EEG) critical dynamic parameters to evaluate thermal comfort. The study aimed to determine the critical dynamic characteristics of brain activity under different thermal conditions, and to establish the relationship between comfort and brain energy consumption. The experiment involved three conditions of cold, neutral, and hot environment, with 20 participants' EEG, thermal sensation vote (TSV), and thermal comfort vote (TCV) collected. The study calculated the critical dynamic parameters of EEG, including the mean frequency, avalanche size, avalanche duration, and branch parameters of brain activity at different temperature levels. The results showed that the parietal occipital lobe, right frontal lobe, and temporal lobe were sensitive to cold and hot, with brain activity tending to be large-scale and long-term during cold environment. In addition, 80% and 35% of the participants had higher brain activity energy consumption in cold environment and hot environment, respectively, compared to the neutral environment. This study represents a new interdisciplinary approach combining medicine and engineering to evaluate indoor thermal comfort, and provides a new research framework and knowledge system for understanding the cognitive activities of the brain in indoor thermal environments, as well as the application of smart buildings.