Relationship between Facial Expression and Facial Electromyogram (f-EMG) Analysis in the Expression of Drowsiness

Various approaches have been utilized in the overall study of facial expressions. And while the results of such research have been reported, little is known about the actual mechanism of how facial expressions are formed. Ishida et al. studied the facial expression of drowsiness. In their study, they discovered that contraction of the frontal is muscle raises the eyebrows when a person is sleepy. However, the correspondence between activity of the frontal is muscle and rising of the eyebrows is not very clear. This study investigated the relationship between them by using non-contact measurement systems and facial EMG. As a result, the relationship between frontal is muscle activity and displacement of rising eyebrows was found to be a linear relationship (R = 0.994). The possibility was also suggested that major changes in expression can occur through coordinated action of muscles on the opposite side.