Background: This study sought to determine how esthetic appearance of babies may affect their motivational processing by the adults.
Methodology and principal findings: Healthy men and women were administered two laboratory-based tasks: a) key pressing to change the viewing time of normal-looking babies and of those with abnormal facial features (e.g., cleft palate, strabismus, skin disorders, Down's syndrome and fetal alcohol syndrome) and b) attractiveness ratings of these images. Exposure to the babies' images produced two different response patterns: for normal babies, there was a similar effort by the two groups to extend the visual processing with lower attractiveness ratings by men; for abnormal babies, women exerted greater effort to shorten the viewing time despite attractiveness ratings comparable to the men.
Conclusions: These results indicate that gender differences in the motivational processing of babies include excessive (relative to the esthetic valuation) motivation to extend the viewing time of normal babies by men vs. shortening the exposure to the abnormal babies by women. Such gender-specific incentive sensitization phenomenon may reflect an evolutionary-derived need for diversion of limited resources to the nurturance of healthy offspring.