Analysis of Brain Stress in Response to Temperature Changes under Agricultural Work Using Electroencephalogram Measurement

Agricultural workers suffer from various physical problems and mental stress, including depression and insomnia. Various factors affect brain stress, including harsh agricultural working conditions. Further brain stress may also be due to changes in working conditions such as temperature, noise, and vibration. This study aimed to determine the brain stress in response to ambient temperature changes under agricultural work using agricultural machinery. The electroencephalograms (EEGs) of 17 agricultural workers who work using various agricultural machines was measured and analyzed. The EEG was measured for 3 min at the inactive and active state of agricultural work, respectively, at 24 °C, 28 °C, and 32 °C. The EEG was analyzed using the stress indices such as spectral edge frequency 95% (SEF95%), relative gamma power (RGP), and EEG-based working index (EWI). The EEG analysis indicated that brain stress was generated when the subjects performed the agricultural work after an inactive state. Additionally, as the temperature increased to ≥24 °C, the brain regions where SEF95%, RGP, and EWI exhibited an increase were identified. The findings of this study can be used as basic data in determining the working stress in agricultural workers during work as the ambient temperature changes from 24 °C to 32 °C.