Weather changes induces physical and mental symptoms such as pain and anxiety. However, no flexible devices have been developed that can be used under physiological conditions, and the relationship between weather changes and brain function remains unknown. We have previously achieved cerebral blood flow monitoring under freely moving conditions using an ultra-compact CMOS imaging device that can be implanted in the mice brain. And recently, we have developed thermocouple device to evaluate the relationship between weather changes and brain temperature. Analysis using CMOS imaging device have revealed no sex differences in changes in brain hemoglobin levels in mice exposed to low barometric pressure environments. On the other hand, analysis using thermocouple devices showed that exposure to a low barometric pressure environment decreased brain temperature only in male mice. In this symposium, we would like to discuss the relationship between barometric pressure fluctuations and brain function and its gender differences.