Kiley Hamlin

A growing body of research has shown that preverbal infants prefer prosocial to antisocial characters, suggesting that the ability to sociomorally evaluate others is early emerging. However, some argue that infants’ responses within these studies reflect low-level perceptual processes rather than social understanding of the events. Using electroencephalography (EEG), the purpose of this research was to address this alternative explanation by examining 1) specific neural signatures that have been associated with social (indexing by P400 and N290 ERP components) versus lower-level attentional processing (indexing by Nc ERP component) and 2) motivational processes involved in infants’ prosocial preferences (indexing by frontal alpha asymmetry for approach/avoidance motivation). Thirty-six 6-month-old infants watched a helping/hindering scenario, in which a character tries but fails to open a box, then is alternatively helped or hindered in opening the box lid. Infants showed greater amplitudes in the P400 component as well as greater N290 component over the right hemisphere channels to hinderers versus helpers (indexing social perception); in contrast, no significant differences were observed for the Nc component (indexing attentional allocation). No motivational processes were observed when infants viewed helping versus hindering videos. Overall, our findings provide evidence for the presence of social processes in infants’ responses to sociomoral actors, suggesting that infants’ responses to sociomoral events are unlikely to be attributable to attentional differences.

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Punishment, despite its negative nature, plays a crucial role in fostering cooperation within human society by deterring antisocial behavior and promoting prosocial behavior in long-term social interactions. Although some evidence suggested children would consider the target's previous prosocial or antisocial actions in their socio-moral evaluation (Geraci, 2021; Hamlin et al., 2011; Lee & Warneken, 2020; Loke et al., 2011), some showed they do not (Li et al., 2020; Li & Tomasello, 2018; Van de Vondervoort, 2020). One possible explanation is that children are opposed to punishment from an ordinary citizen who is not in the position to punish. We hypothesize that children may perceive punishment as acceptable when carried out by authority figures. To explore this hypothesis, the present study investigated whether 3- and 4-year-old children would consider the context in which helping and hindering occur in their evaluations when the moral agents were depicted as holding authority status.Contrary to our prediction, both 3- and 4-year-old children negatively evaluated the punishing police officers and positively evaluated the rewarding police officer regardless of whether the target was previously prosocial or antisocial. They preferred the rewarding police officer when asked about liking, the rightness of the action, and identifying the good police officer. We discussed possible reasons for our failure to detect children's context-dependent moral evaluations using the current study design, and proposed future direction to explore this topic. These findings contribute to our understanding of how contextual information influences children's moral judgment about third-party interventions and shed light on the developmental trajectory of children's sociomoral cognition.

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Research in the past two decades has found evidence for dehumanization in both adults and children; however, its developmental origins – that is, whether young infants already possess the tendency to dehumanize others – has yet to be investigated. The present study examined whether 11-month-old infants already dehumanize out-group members by denying out-group others of certain mental states, a common measure of dehumanization in adults and children. To do so, the study examined infants’ attribution of goals, a basic mental state infants readily attribute to human agents. Sixty-two primarily English-hearing infants watched videos in which a female experimenter, either speaking in English or Spanish, reached for one of two objects. At test, the two objects switched places, and infants’ looking times were measured as the experimenter either reached for the same object or a different object. Infants who watched the English speaker were surprised, and thus looked longer, when she reached for a different object, suggesting that they attributed a goal of the original object to the English speaker. By contrast, infants watched both types of reaches equally if they saw the Spanish speaker. Exploratory analyses examined the impact of age and language exposure on infants’ goal attribution to in-group and out-group members. These findings suggest that infants as young as 11 months of age may already show the tendency to deny out-group others of certain mental states. We discuss the implications of these findings as it relates to the nature of dehumanization and the emergence of intergroup bias.

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Within the last five years, social sciences, especially psychology, have seen problems with replicability and reproducibility. A growing body of evidence suggests that low powered studies, undisclosed statistical flexibility and lack of pre-specified study standards are all contributing factors to a low rate of replicability. Within the realm of infant social evaluation, a topic of both theoretical interest and empirical controversy, both replications and non- replications exist. Given this, and the movement toward replication in psychology in general, this paper will present results both a pre-registered sample and a larger sample that directly replicates Hamlin & Wynn’s (2011) “box scenario”, which examines whether preverbal infants prefer prosocial to antisocial others. Our pre-registered sample did not replicate the original finding seen in Hamlin & Wynn (2011). However, when including all infants tested in the box scenario, the finding did indeed replicate. Overall, our findings add to the scientific understanding of infant social evaluation and provide an important opportunity to add to the replicability movement.

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The present study examined developmental continuity in social functioning from infancy to preschool. Specifically, we examined the relationships between infants’ performance on sociomoral evaluation studies and parent report of their preschool social functioning. Infants’ performance, emotional stability (fuss-out rate), and average habituation rate in moral evaluation tasks were collected. Preschool social functioning was measured through parent-report online scales. The results showed 1) that better performance on infant moral evaluation studies was associated with lower rates of parent report of preschool attention problems, social responsiveness problems, and callousness-unemotional traits, as well as higher rates of parent report of adaptive social skills, 2) that fuss-out rate across infant moral evaluation studies was positively associated with parent report of preschool anxiety, depression, and withdrawal, 3) that the relationships between the performance on infant moral evaluation studies and parent-report preschool functioning were stronger for males than for females, and that 4) these relationships were domain-specific. Together these findings provide preliminary evidence for longitudinal continuity in social functioning from infancy to preschool.

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Mature moral judgments rely on the analysis of both the outcomes of others’ actions and the mental states that drive them. Past research has shown that when there is conflict between outcome and intention, young children rely on outcome information to evaluate others, while older children and adults privilege intention (Piaget, 1932/1965). This suggests that there is a shift from outcome-based to intention-based judgments occurring in development.However, the current study suggests that even 10-month-old infants evaluate moral agents on the basis of their underlying mental states. Infants were presented with puppet shows in which a protagonist was either intentionally or accidentally helped or hindered. Infants were then given a forced choice between the accidental and intentional puppets. Results indicate that infants’ preference for the accidental versus the intentional character differed by condition [χ²(1, N = 60)= 11.28, p .001, ϕ = .43]; infants preferred intentional to accidental helpers (Binomial, p .05), but preferred accidental to intentional hinderers (Binomial, p .05). These results suggest that the capacity to evaluate others on the basis of intention arises much earlier on in development than previously suggested and contradicts earlier claims of a developmental shift from outcome- to intention-based judgments.

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