Noncontact Measurement for the Autonomic Nervous System through RGB Camera

In this study, we focused on the color change in video, green and red values because the absorption efficiency of hemoglobin is different. When the autonomic nervous system activates, vasodilation or vasoconstriction occurs. With reference to these phenomena, the reaction of RG in the video is considered to indicate the contraction and expansion reaction of blood vessels, that is, the reaction of autonomic nerves. To prove it, we conducted a verification experiment. The changes green and red values of video image and the in heart rate (HR) were simultaneously measured during a cold water load test. The HR data was used for valuation. As a result, it was confirmed that the green and red values fluctuated in response to that of HR.