The perception of facial expressions by the three-month-old.

We used habituation to investigate 3-month-olds' abilities to discriminate and recognize smiling and frowning expressions posed by the mother or by a female stranger. Infants discriminated between the expressions and recognized which expression they had seen during the habituation trials; they did so whether the expressions were posed by the mother or by the stranger. However, when the expressions were posed by the mother, more infants showed …