Tuning the developing brain to emotional body expressions

Abstract

Reading others' emotional body expressions is an essential social skill. Adults readily recognize emotions from body movements. However, it is unclear when in development infants become sensitive to bodily expressed emotions. We examined event-related brain potentials (ERPs) in 4- and 8-month-old infants in response to point-light displays (PLDs) of happy and fearful body expressions presented in two orientations (upright and inverted). The ERP results revealed that 8-month-olds but not 4-month-olds respond sensitively to the orientation and the emotion of the dynamic expressions. Specifically, 8-month-olds showed (i) an early (200-400 ms) orientation-sensitive positivity over frontal and central electrodes, and (ii) a late (700-1100 ms) emotion-sensitive positivity over temporal and parietal electrodes in the right hemisphere. These findings suggest that orientation-sensitive and emotion-sensitive brain processes, distinct in timing and topography, develop between 4 and 8 months of age. Reading others' emotional body expressions is an essential social skill. Adults are readily able to recognize emotions from body movements. However, it is unclear when in development infants become sensitive to bodily expressed emotions. In this study ERPs were measured in 4-and 8-month-old infants in response to happy and fearful body expressions using point-light displays (PLDs) presented in two orientations, upright and inverted. The ERP results revealed that only 8-month-olds but not 4-month-olds respond sensitively to the orientation and the emotion of the dynamic expressions. These findings suggest that orientation-sensitive and emotion-sensitive brain processes develop between 4 and 8 months of age.