Shades of emotion: What the addition of sunglasses or masks to faces reveals about the development of facial expression processing

► 3-4 year-old children identify expressions better if the faces wear sunglasses. ► The effect of sunglasses is reversed by 10 years of age. ► After age 10, sunglasses impair expression identification as much as face inversion. ► Adults also showed impaired classification if faces wore surgical masks. ► Young children showed no impairment for faces wearing surgical masks.