Characteristics of facial skin blood flow that fluctuates with emotions

Abstract

Emotions are accompanied by physical reactions, such as facial expressions and heart rate changes. This paper focuses on facial skin blood flow (SkBF) as an index of the autonomic nervous system. Facial SkBF is a unique indicator compared to heart rate or sweating because it is related to facial temperature and facial color changes. The SkBF does not react uniformly in all areas of the face and has different reactivity in each part of the face, such as the forehead, cheek, or nose. In several previous studies, the time window for the analyses was about 30 seconds or more, however, focusing on short-term rapid responses, e.g. 5 seconds, is critical for clarifying the mechanisms of mental disorders related to facial SkBF and clinical intervention.