Characteristics of the Skin Perceived during Facial Expressions and Its Age-Related Change

The previous studies on the aging of skin have mainly targeted the facial skin of the serious looks of so-called static faces. However, our faces present facial expressions. When these expressions are made, the skin is in a “dynamic” state where it changes its shape and position, so it is possible that there are characteristics of aging that do not appear in a face that has a serious expression on it. By visually detecting these characteristics, we think that it is possible to get a variety of impressions about aging. Therefore, the purpose of this investigation was to clarify the types of characteristics of the changes in the skin that can be ascertained from appearance that are expressed when the face changes to a facial expression from a passive look. It is also to subsequently clarify the changes in these characteristics that accompany aging. To do this, an investigation was done using the image analysis method and visual assessment tests on the footage taken. This resulted in the extraction of 4 types of characteristic changes to the skin that occur when the face changes from a passive look to making a facial expression, and these were extracted using visual assessments. Additionally, upon analysis of two types of these characteristics, “area of overly bright (overexposed) skin” and “fine linear structures area around the pore” using the footage taken, it was shown that aging was accompanied by a tendency towards an increase in the average value between facial expressions and in the amount (standard deviation) of fluctuation between facial expressions.