Emotional expressions of female and male infants in a social and a nonsocial context

While observational studies of the emotional expressions of women and men have revealed several consistent patterns of gender differences, data pertaining to the emotional expressions of male and female infants are largely inconsistent. Attempting to trace the course of early emotional development in female and male infants, we undertook to compare the emotional expressions of boys and girls at 2 1/2 and 5 months of age in a variety of situations. All infants who participated in the study were from French-speaking Caucasian families of low and middle class. At each age level, infants were observed in a social and nonsocial situation. The social situation began with a mother—infant interaction, followed by a period during which the mother remained silent and still-faced. In the nonsocial situation, a mobile was presented and then removed. Infants' facial expressions were coded using the AFFEX system. Direction of gaze was also coded. Overall, boys' and girls' reactions were quite similar. At both ages, male and female infants spent more time looking at the toy than at their mother and showed more expressions of interest toward the toy. They also smiled more while interacting with their mother and displayed more negative expressions when facing their still-faced mother. One gender difference was found: At 2 1/2 months, girls smiled more than boys while interacting with their mother. Several explanations are proposed to account for these findings.