When people look at someone, they unconsciously figure out how old that person is by studying the contrasting nature of his or her facial features. Or so says Psychology Professor Richard Russell, who has been collaborating with researchers from CE.R.I.E.S. (Epidermal and Sensory Research and Investigation Center), a department of Chanel Research and Technology dedicated to skin-related issues and facial appearance.
"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 in a press release.
He said the discovery of this tip-off to age perception may partly explain why people wear makeup in the way they do. For example, lipstick that makes the lips redder is actually making the face appear younger, he added.
As part of the study, Russell and his team measured images of 289 faces ranging in age from 20 to 70 years old, and found that -- through the aging process -- the color of the lips, eyes and eyebrows change, while the skin becomes darker. The end result is less contrast between the features and the surrounding skin -- leaving older faces to have less contrast than younger ones.
The difference in redness between the lips and the surrounding skin decreases, as does the luminance difference between the eyebrow and the forehead, as the face ages. Although not consciously aware of this sign of aging, the mind uses it as a clue for perceiving how old someone is.
In another study involving more than 100 subjects in Gettysburg, Pennsylvania and Paris, the scientists artificially increased these facial contrasts and found that the faces were believed to be younger. When they artificially decreased the facial contrasts, the faces were believed to be older, researchers said.
Previously Russell has studied the greater contrast in female faces between the eyes, mouth and the rest of the face. He said that people use this sex difference in facial contrast to decide whether a face is male or female.
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