High-Resolution Bio-potential and Bio-impedance Investigation of the Face

Abstract The importance of facial muscles is evident in the critical role they play in numerous functions. The purpose of some actions (e.g. chewing, swallowing) is clear. Others, such as yawning and the expression of emotion are more elusive. Despite their ubiquity, the manner by which facial muscles affect physiological processes is not clear. In particular, how facial muscles affect blood flow has received little attention. Here we present a new wearable approach to investigate the face. Soft electrode arrays were used to detect subtle changes in blood flow in the temporal superficial artery following muscle activity. Changes in response to muscle activation are clearly evident and conspicuously more complex than in the forearm. Simultaneous bio-potential and bio-impedance mapping of the face unravels the complex manner by which these muscles help shape human physiology.