Infants’ neural responses to helping and hindering scenarios

A growing literature suggests infants prefer prosocial others over antisocial others. Although recent studies have begun to explore the neural mechanisms underlying these responses (Cowell and Decety, 2015; Gredebäck et al., 2015), these studies were based on relatively small samples and focused on distinct aspects of sociomoral responding. The current preregistered study systematically examined infants’ neural responses both to prosocial/antisocial interactions and to prosocial/antisocial characters, using larger samples and two distinct age groups. We found that 6- (but not 12-) month-olds showed higher relative right frontal alpha power (indexing approach motivation) when viewing helping versus hindering scenarios. Consistent with past EEG work, infants showed no group-level manual preferences for the helper. However, analyses of infants’ neural responses toward images of the helper versus hinderer revealed that both 6- and 12-month-olds showed differential event-related potential (ERP) responses in the P400 and N290 components (indexing social perception) but not in the Nc component (indexing attentional allocation), suggestive that infants’ neural responses to prosocial versus antisocial characters reflect social processing. Together, these findings provide a more comprehensive account of infants’ responses to prosocial/antisocial interactions and characters, and support the hypothesis that both motivational and socially relevant processes are implicated in infants’ sociomoral responding.