As people age, there is less contrast between their facial features and the surrounding skin. According to Richard Russell, a psychology professor at Gettysburg College, this is one of the signals that we unconsciously use to figure out how old someone looks.
In one study, Russell and his team measured images of 289 faces between the ages of 20 and 70, and found that as a person becomes older, the color of the lips, eyes and eyebrows change, while the skin becomes darker. This results in older faces having less contrast than younger faces.
“Unlike with wrinkles, none of us are consciously aware that we’re using this cue, even though it stares us in the face every day,” said Russell.
The discovery of this cue to facial age perception may partly explain how we use cosmetics, and it lends more evidence to the idea that current cosmetic use reflects our biological as well as our cultural heritage, according to Russell.
As a person ages, the difference between the redness of the lips and the surrounding skin decreases, as does the luminance difference between the eyebrow and the forehead. Even though we are not consciously aware of this sign of aging, the mind uses it as a cue for perceiving how old someone is.
In another study which included over a hundred participants in Gettysburg and Paris, the scientists artificially increased these facial contrasts and found that the faces were perceived as younger. When they artificially decreased the facial contrasts, the faces were perceived as older.
Makeup is commonly used to increase the contrast of facial features. Scientists propose that this can partly explain why makeup is worn the way that it is. For example, cosmetics that increase the redness of the lips make the face appear younger, which is related to healthiness and beauty.
For the study, Russell collaborated with researchers from CE.R.I.E.S. (Epidermal and Sensory Research and Investigation Center), a department of Chanel Research and Technology that studies skin related issues and facial appearance.
The study is published in the open-access journal PLOS ONE.
Source: Gettysburg College