Bodily markers of basic emotions: a thermographic study

Skin temperature has been recognized as a potential marker of emotional arousal, with studies demonstrating temperature changes in response to various emotional stimuli. However, temperature in different body parts and in different basic emotions has not been studied sufficiently. Our study aimed to investigate whether basic emotions could be reflected in temperature changes at specific body surfaces. Forty healthy subjects viewed blocks of pictures inducing six basic emotions and neutral images while their temperature at the shoulder, throat, chest, and temple was recorded. In addition, electrodermal activity and electrocardiograms were captured as control variables. We showed, first, temperature at the chest, on average, increased, and its change was higher than at other regions. Second, chest temperature increased in various emotions such as fear, surprise, and happiness. Third, chest temperature correlated with heart rate; therefore, it may reflect the cardiac activity. Fourth, temperatures in different regions did not correlate, suggesting a specificity of thermal reactions. Our results revealed associations between specific emotions and temperature changes at different body surfaces. We indicate the need for further research with more specific designs, stronger induction methods, and additional physiological measures, such as facial muscle activity.<b>NEW & NOTEWORTHY</b> We studied whether basic emotions could be reflected in temperature changes at specific body surfaces. Healthy subjects viewed pictures inducing six basic emotions and neutral images with temperature at the shoulder, throat, chest, and temple being recorded. Chest temperature was higher than at other regions and increased in various emotions such as fear, surprise, and happiness. It correlated with heart rate. Temperature in different regions did not correlate, suggesting a specificity of thermal reactions.