Smiling makes you look older, even when you wear a mask: the effect of face masks on age perception.

For old adults, there was an unexpected trend in the opposite direction, with smiling female [ F (1,82) = 4.22, p < 0.05, η p 2 = 0.05] and male faces [ F (1,82) = 4.91, p < 0.05, η p 2 = 0.06] perceived as younger than neutral faces.

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