Infants possess an abstract expectation of ingroup support

Infants expect some degree of positive and negative reciprocity between strangers

Social scientists from different disciplines have long argued that direct reciprocity plays an important role in regulating social interactions between unrelated individuals. Here, we examine whether 15-month-old infants (N = 160) already expect direct positive and negative reciprocity between strangers. In violation-of-expectation experiments, infants watch successive interactions between two strangers we refer to as agent1 and agent2. After agent1 acts positively toward agent2, infants are surprised if agent2 acts negatively toward agent1 in a new context. Similarly, after agent1 acts negatively toward agent2, infants are surprised if agent2 acts positively toward agent1 in a new context. Both responses are eliminated when agent2's actions are not knowingly directed at agent1. Additional results indicate that infants view it as acceptable for agent2 either to respond in kind to agent1 or to not engage with agent1 further. By 15 months of age, infants thus already expect a modicum of reciprocity between strangers: Initial positive or negative actions are expected to set broad limits on reciprocal actions. This research adds weight to long-standing claims that direct reciprocity helps regulate interactions between unrelated individuals and, as such, is likely to depend on psychological systems that have evolved to support reciprocal reasoning and behavior.

The Cognitive Architecture of Infant Attachment

Meta-analytic evidence indicates that the quality of the attachment relationship that infants establish with their primary caregiver has enduring significance for socioemotional and cognitive outcomes. However, the mechanisms by which early attachment experiences contribute to subsequent development remain underspecified. According to attachment theory, early attachment experiences become embodied in the form of cognitive-affective representations, referred to as internal working models (IWMs), that guide future behavior. Little is known, however, about the cognitive architecture of IWMs in infancy. In this article, we discuss significant advances made in the field of infant cognitive development and propose that leveraging insights from this research has the potential to fundamentally shape our understanding of the cognitive architecture of attachment representations in infancy. We also propose that the integration of attachment research into cognitive research can shed light on the role of early experiences, individual differences, and stability and change in infant cognition, as well as open new routes of investigation in cognitive studies, which will further our understanding of human knowledge. We provide recommendations for future research throughout the article and conclude by using our collaborative research as an example.

Infants Infer Social Relationships Between Individuals Who Engage in Imitative Social Interactions

Infants are born into rich social networks and are faced with the challenge of learning about them. When infants observe social interactions, they make predictions about future behavior, but it is not clear whether these predictions are based on social dispositions, social relationships, or both. The current studies (N = 188, N = 90 males) address this question in 12-month-old infants and 16- to 18-month-old toddlers who observe social interactions involving imitation. In Studies 1 and 3, infants and toddlers expected that imitators, compared to non-imitators, would respond to their social partners' distress. Likewise, they expected the targets of imitation, compared to non-targets, to respond to their partner's distress. In Study 2, these expectations did not generalize to interactions with a new partner, providing evidence that infants learned about the relationships between individuals as opposed to their dispositions. In Study 3, infants did not make predictions about responses to laughter, suggesting that infants see imitation as indicative of a specific kind of social relationship. Together, these results provide evidence that imitative interactions support infants' and toddlers' learning about the social relationships connecting unknown individuals.

Better Together: 14-Month-Old Infants Expect Agents to Cooperate

Humans engage in cooperative activities from early on and the breadth of human cooperation is unparalleled. Human preference for cooperation might reflect cognitive and motivational mechanisms that drive engagement in cooperative activities. Here we investigate early indices of humans' cooperative abilities and test whether 14-month-old infants expect agents to prefer cooperative over individual goal achievement. Three groups of infants saw videos of agents facing a choice between two actions that led to identical rewards but differed in the individual costs. Our results show that, in line with prior research, infants expect agents to make instrumentally rational choices and prefer the less costly of two individual action alternatives. In contrast, when one of the action alternatives is cooperative, infants expect agents to choose cooperation over individual action, even though the cooperative action demands more effort from each agent to achieve the same outcome. Finally, we do not find evidence that infants expect agents to choose the less costly alternative when both options entail cooperative action. Combined, these results indicate an ontogenetically early expectation of cooperation, and raise interesting implications and questions regarding the nature of infants' representations of cooperative actions and their utility.

Condemned or valued: Young children evaluate nonconformity based on nonconformists' group orientations

Nonconformity--the act of deviating from established norms and expectations of one's group--is often evaluated negatively, despite its potential benefits for society. Three preregistered studies (N = 153) examined how nonconformists' group orientations (attitudes and intentions toward ingroup and outgroups) might affect 4-6-year-olds' evaluations of nonconformity in intergroup situations. Study 1 examined children's default beliefs of nonconformists' group attitudes toward ingroup and outgroup. We found that children expected nonconformists to hold more positive attitudes toward their outgroup than toward their ingroup, and this expectation predicted their disapproval of nonconformity. In Study 2, however, when nonconformity was explicitly motivated by positive intentions toward the ingroup rather than toward the outgroup, children were more accepting of nonconformity. Study 3 found that among nonconformists with different types of group orientations (positive toward the outgroup, ingroup or both group), young children evaluated the most positively nonconformists who bring the ingroup and the outgroup together. Collectively, these findings suggest that children evaluate nonconformity based on nonconformists' group orientations, illuminating one mechanism for how nonconformity could be more socially accepted and valued.

Infants expect friends, but not rivals, to be happy for each other when they succeed

A friend telling you good news earns them a smile while witnessing a rival win an award may make you wrinkle your nose. Emotions arise not just from people's own circumstances, but also from the experiences of friends and rivals. Across three moderated, online looking time studies, we asked if human infants hold expectations about others' vicarious emotions and if they expect those emotions to be guided by social relationships. Ten- and 11-month-old infants (N = 154) expected an observer to be happy rather than sad when the observer watched a friend successfully jump over a wall; infants looked longer at the sad response compared to the happy response. In contrast, infants did not expect the observer to be happy when the friend failed, nor when a different, rival jumper succeeded; infants' looking times to the two emotion responses in these conditions were not reliably different. These results suggest that infants are able to integrate knowledge across social contexts to guide expectations about vicarious emotional responses. Here infants connected an understanding of agents' goals and their outcomes with knowledge of social relationships to infer an emotion response. Biased concern for friends but not adversaries is not just a descriptive feature of human relationships, but an expectation about the social world present from early in development. Further, the successful integration of these information types welcomes the possibility that infants can jointly reason about goals, emotions, and social relationships under an intuitive theory of psychology. RESEARCH HIGHLIGHTS: 11-month-old infants use knowledge of relationships to make inferences about others' vicarious emotions. In Experiment 1 infants expected an observer to respond happily to a friend's success but not their failure. Experiments 2 and 3 varied the relationship between the observer and actor and found that infants' expectation of vicarious happiness is strongest for positive relationships and absent for negative relationships. The results may reflect an intuitive psychology in which infants expect friends to adopt concern for one another's goals and to thus experience one another's successes as rewarding.

Children's Reasoning About Empathy and Social Relationships

Across the lifespan, empathic and counter-empathic emotions are shaped by social relationships. Here we test the hypothesis that this connection is encoded in children's intuitive theory of psychology, allowing them to predict when others will feel empathy versus counter-empathy and to use vicarious emotion information to infer relationships. We asked 4- to 7-year-old children (N = 79) to make emotion predictions or relationship inferences in response to stories featuring two characters, an experiencer and an observer, and either a positive or negative outcome for the experiencer. In the context of positive outcomes, we found that children engaged in robust joint reasoning about relationships and vicarious emotions. When given information about the characters' relationship, children predicted empathy from a friendly observer and counter-empathy from a rival observer. When given information about the observer's response to the experiencer, children inferred positive and negative relationships from empathic and counter-empathic responses, respectively. In the context of negative outcomes, children predicted that both friendly and rival observers would feel empathy toward the experiencer, but they still used information about empathic versus counter-empathic responses to infer relationship status. Our results suggest that young children in the US have a blanket expectation of empathic concern in response to negative outcomes, but otherwise expect and infer that vicarious emotions are connected to social relationships. Future research should investigate if children use this understanding to select social partners, evaluate their own relationships, or decide when to express empathy toward others.

Teenagers' but not young adults' beliefs about intrinsic interpersonal obligations for group members

Previous research has indicated that children perceive social category members as having intrinsic obligations toward each other, which shape their expectations for social interactions. However, it is unclear whether teenagers (aged 13 to 15) and young adults (aged 19 to 21) continue to hold such beliefs, given their increased experience with group dynamics and external social rules. To explore this question, three experiments were conducted with a total of 360 participants (N = 180 for each age group). Experiment 1 examined negative social interactions using different methods in two sub-experiments, while Experiment 2 focused on positive social interactions to examine whether participants viewed social category members as intrinsically obligated to avoid harming each other and to offer assistance. Results revealed that teenagers evaluated within-group harm and non-help as unacceptable, regardless of external rules, whereas they viewed between-group harm and non-help as both acceptable and unacceptable, depending on the presence of external rules. Conversely, young adults considered both within-group and between-group harm/non-help as more acceptable if an external rule permitted such behavior. These findings suggest that teenagers believe that members of a social category are intrinsically obligated to help and not harm each other, whereas young adults believe that individual social interactions are constrained mainly by external rules. That is, teenagers hold stronger beliefs than young adults about intrinsic interpersonal obligations to group members. Thus, in-group moral obligations and external rules contribute differently to the evaluation and interpretation of social interactions at different developmental stages.

Human and animal dominance hierarchies show a pyramidal structure guiding adult and infant social inferences

This study investigates the structure of social hierarchies. We hypothesized that if social dominance relations serve to regulate conflicts over resources, then hierarchies should converge towards pyramidal shapes. Structural analyses and simulations confirmed this hypothesis, revealing a triadic-pyramidal motif across human and non-human hierarchies (114 species). Phylogenetic analyses showed that this pyramidal motif is widespread, with little influence of group size or phylogeny. Furthermore, nine experiments conducted in France found that human adults (N = 120) and infants (N = 120) draw inferences about dominance relations that are consistent with hierarchies' pyramidal motif. By contrast, human participants do not draw equivalent inferences based on a tree-shaped pattern with a similar complexity to pyramids. In short, social hierarchies exhibit a pyramidal motif across a wide range of species and environments. From infancy, humans exploit this regularity to draw systematic inferences about unobserved dominance relations, using processes akin to formal reasoning.

Rational learners and parochial norms

Parochial norms are narrow in social scope, meaning they apply to certain groups but not to others. Accounts of norm acquisition typically invoke tribal biases: from an early age, people assume a group's behavioral regularities are prescribed and bounded by mere group membership. However, another possibility is rational learning: given the available evidence, people infer the social scope of norms in statistically appropriate ways. With this paper, we introduce a rational learning account of parochial norm acquisition and test a unique prediction that it makes. In one study with adults (N = 480) and one study with children ages 5- to 8-years-old (N = 120), participants viewed violations of a novel rule sampled from one of two unfamiliar social groups. We found that adults judgments of social scope - whether the rule applied only to the sampled group (parochial scope), or other groups (inclusive scope) - were appropriately sensitive to the relevant features of their statistical evidence (Study 1). In children (Study 2) we found an age difference: 7- to 8-year-olds used statistical evidence to infer that norms were parochial or inclusive, whereas 5- to 6-year olds were overall inclusive regardless of statistical evidence. A Bayesian analysis shows a possible inclusivity bias: adults and children inferred inclusive rules more frequently than predicted by a naïve Bayesian model with unbiased priors. This work highlights that tribalist biases in social cognition are not necessary to explain the acquisition of parochial norms.

Oxytocin attenuates racial categorization in 14-month-old infants

Intergroup bias - the preferential attitudes one holds towards one's social group - is a ubiquitous socio-cognitive phenomenon. In fact, studies show that already in the first months of life, infants manifest a preference for members of their own social group. This points to the possibility of inborn mechanisms involved in social group cognition. Here we assess the effect of a biological activation of infants' affiliative motivation on their social categorization capacity. In a first visit to the lab, mothers self-administered either Oxytocin (OT) or placebo (PL) via a nasal spray and then engaged in a face-to-face interaction with their 14-month-old infants, a procedure previously shown to increase OT levels in infants. Infants then performed a racial categorization task presented on an eye-tracker. Mothers and infants returned a week later and repeated the procedure while self-administering the complementary substance (i.e., PL or OT, respectively). In total, 24 infants completed the two visits. We found that whereas infants in the PL condition on the first visit exhibited racial categorization, infants in the OT condition in their first visit did not. Moreover, these patterns remained a week later despite the change in substance. Thus, OT inhibited racial categorization when infants first encountered the to-be-categorized faces. These findings highlight the role of affiliative motivation in social categorization, and suggest that the neurobiology of affiliation may provide insights on mechanisms that may be involved in the downstream prejudicial consequences of intergroup bias.

The sense of belonging reduces ingroup favoritism in children

Belonging is an important motive for intergroup behavior. Adults display pronounced ingroup favoritism when the sense of inclusion by an ingroup is decreased or threatened. The present study investigated whether ingroup belonging reduces ingroup favoritism in 6-year-old children in terms of costly sharing. Children were allocated to a novel group in a minimal-group paradigm. In two conditions, children played a brief ball-tossing game and were either included (ingroup-inclusion condition) or excluded (ingroup-exclusion condition) by their ingroup members. Children in a no-interaction condition did not have any interactions with the members of the ingroup. After this manipulation, we tested the extent to which children shared resources with ingroup and outgroup members. We found that children in the ingroup-exclusion and no-interaction conditions shared more resources with their ingroup member than their outgroup member, while children in the ingroup-inclusion condition shared equally with the ingroup and outgroup members. These results could inform interventions aimed at fostering positive intergroup relations.

The influence of language input on 3-year-olds' learning about novel social categories

There is considerable variability in the social categories that children essentialize and the types of expectations children form about these categories, suggesting children's essentialist beliefs are shaped by environmental input. Prior studies have shown that exposure to generic statements about a social category promotes essentialist beliefs in 4.5- to 8-year-old children. However, by this age children form essentialist beliefs quite robustly, and thus it is unclear whether generic statements impact children's expectations about social categories at younger ages when essentialist beliefs first begin to emerge. Moreover, in prior studies the generic statements were delivered by an experimenter and carefully controlled, and thus it is unclear whether these statements would have the same impact if they occurred in a somewhat less constrained setting, such as parents reading a picture book to their child. The current study addressed these open questions by investigating whether generic statements delivered during a picture-book interaction with their parents influenced 3-year-olds' expectations about members of a novel social category. Our results showed that children who heard generic statements during the picture-book interaction used social-group membership to make inferences about the likely behavior of a novel category member, whereas children who were not exposed to generic statements did not. These findings suggest that as early as 3 years of age, children's expectations about social categories are influenced by generic statements that occur during brief parent-child interactions.

How cues to social categorization impact children's inferences about social categories

Social categorization involves two crucial processes: First, children seek properties on which they can categorize individuals, i.e., they learn to form social categories; then children make inferences based on social category membership and might develop affective responses toward social categories. Over the last decade, a growing number of research in developmental psychology started to use novel social categories to investigate how children learn and reason about social categories. To date, three types of cues have been put forward as means to form social categories, namely linguistic, visual, and behavioral cues. Based on social category membership, children draw inferences about the shared properties of social category members and about how social category members ought to behave and interact with each other. With additional input, children might apply essentialist beliefs to social categories and develop affective responses toward social categories. This article aims to provide key insights on the development of stereotypes and intergroup biases by reviewing recent works that investigated how children learn to form novel social categories and the kind of inferences they make about these novel social categories.

Which group matters more: The relative strength of minimal vs. gender and race group memberships in children's intergroup thinking

Experimentally created "minimal" social groups are frequently used as a means to investigate core components of intergroup cognition in children and adults. Yet, it is unclear how the effects of such arbitrary group memberships compare to those of salient real-world group memberships (gender and race) when they are directly pitted against each other in the same studies. Across three studies, we investigate these comparisons in 4-7-year-olds. Study 1 (N = 48) establishes the minimal group paradigm, finding that children develop ingroup preferences as well as other forms of group-based reasoning (e.g., moral obligations) following random assignment to a minimal group. Study 2 (N = 96) and Study 3 (N = 48) directly compare this minimal group to a real-world social group (gender or race) in a cross-categorization paradigm, in which targets are participants' ingroups in terms of the minimal group and outgroups in terms of a real-world social group, or vice versa. The relative strength of the minimal group varies, but in general it either has a similar effect or a stronger effect as compared to race and in some cases even gender. Our results support the contention that an abstract tendency to divide the world into "us" and "them" is a central force in early intergroup cognition.

Developmental antecedents of representing "group" behavior: A commentary on Pietraszewski's theory of groups

Central to Pietraszewski's theory is a set of group-constitutive roles within four triadic primitives. Although some data from the developmental and biological sciences support Pietraszewski's theory, other data raise questions about whether similar behavioral expectations hold across various ecological conditions and interactions. We discuss the potential for a broader set of conceptual primitives that support reasoning about groups.

Young Children’s Conceptualisations of Kindness: A Thematic Analysis

Although there is much interest in the development of prosocial behaviour in young children, and many interventions that attempt to cultivate kindness in children, there is a paucity of research exploring children’s lived experiences of kindness and including their voices. In this study, children’s understanding of kindness is approached through qualitative interviews using puppets. Interviews were conducted with 33 children aged 5-6 years in 3 schools in the United Kingdom. Through thematic analysis, 4 themes were developed: (a) doing things for others, (b) relating with others, (c) rules and values, and (d) kindness affects us. These themes are examined in light of current thinking on prosocial and sociomoral development, and several key insights are highlighted, including types of prosocial behaviour, social connection, kindness-by-omission and defending, in-group bias, universal kindness versus personal safety, self-image, and a desire to improve the condition of society. These findings have implications for future research on prosocial development and for the design of kindness-based interventions, as well as providing an ecologically valid method of inquiry for use with young children.

Adopted Utility Calculus: Origins of a Concept of Social Affiliation

To successfully navigate their social world, humans need to understand and map enduring relationships between people: Humans need a concept of social affiliation. Here I propose that the initial concept of social affiliation, available in infancy, is based on the extent to which one individual consistently takes on the goals and needs of another. This proposal grounds affiliation in intuitive psychology, as formalized in the naive-utility-calculus model. A concept of affiliation based on interpersonal utility adoption can account for findings from studies of infants' reasoning about imitation, similarity, helpful and fair individuals, "ritual" behaviors, and social groups without the need for additional innate mechanisms such as a coalitional psychology, moral sense, or general preference for similar others. I identify further tests of this proposal and also discuss how it is likely to be relevant to social reasoning and learning across the life span.

When Are Similar Individuals a Group? Early Reasoning About Similarity and In-Group Support

Beginning in infancy, children expect individuals in a group to care for and be loyal to in-group members. One prominent cue that children use to infer that individuals belong to the same group is similarity. Does any salient similarity among individuals elicit an expectation of in-group preference, or does contextual information modulate these expectations? In Experiments 1 and 2, 12-month-old infants expected in-group preference between two individuals who wore the same novel outfit, but they dismissed this similarity if one of the outfits was used to fulfill an instrumental purpose. In Experiment 3, 26-month-old toddlers expected in-group preference between two individuals who uttered the same novel labels, but they dismissed this similarity if the labels were used to convey incidental as opposed to categorical information about the individuals. Together, the results of these experiments (N = 96) provide converging evidence that from early in life, children possess a context-sensitive mechanism for determining whether similarities mark groups.

Inclusion of Refugee Peers - Differences Between Own Preferences and Expectations of the Peer Group

Given the high numbers of refugees from Syria entering Germany in the recent years, the social integration of refugee youth has become an increasingly important issue in Germany. Thus, the current study examines adolescents' decisions and reasoning around the inclusion of Syrian peers in Germany. Using a hypothetical scenario, we assessed adolescents' (N = 100, M = 13.65 years, SD = 1.93, 51 females, 49 males) peer inclusion decisions and reasoning with attention to comparing inclusion of a Syrian refugee peer and a German peer. Given the importance of group norms for adolescents, we assessed not only adolescents' own inclusion decisions, but also what they would expect their peer group to decide and what they think their peer group should do. Moreover, adolescents' underlying reasoning was assessed. The analyses revealed that adolescents thought they would be more inclusive of a Syrian peer than a German peer and that their peer group should be more inclusive of a Syrian peer than a German peer. These tendencies toward including refugees were justified with references to morality as well as social-conventions. In contrast to their own decisions and to what they think their peer group should, participants expected their group would be more inclusive toward a German peer than a Syrian peer. This was mainly justified by referencing aspects of group functioning and psychological information about the peers, whereas moral and prosocial reasoning was very rarely used for the expected group decision. In sum, these findings document that adolescents in Germany wish to be inclusive regarding refugee peers and that they balance attention to morality and other domains of social reasoning when thinking about inclusion decisions while they expect that their peers will not consider morally relevant information when making these decisions. These findings have important practical implications as they indicate the importance of interventions that focus on promoting inclusive peer group norms.

Ingroup favoritism overrides fairness when resources are limited

Ingroup favoritism and fairness are two potentially competing motives guiding intergroup behaviors in human. Here, we investigate if and how limited resources can modulate the way these two motives affect individuals' decisions in intergroup situation. In the present study, participants (N = 58) were asked to accept or reject three types of resource allocation proposals generated by a computer: the ingroup advantageous condition, outgroup advantageous condition, and neutral condition. In general, participants were more willing to accept the proposals in the ingroup advantageous condition than the outgroup advantageous or the neutral conditions, and also in the moderate inequality than the extreme inequality condition. This may indicate that people sought a careful balance between ingroup favoritism and fairness, although we also found marked individual differences in their preferences for ingroup favoritism or fairness. Importantly, as predicted, participants were more likely to show ingroup favoritism only when limited resources affect the well-being of ingroup members. The present study provides novel insights into the situational and personality factors affecting human intergroup behaviors, shedding light on motives underlying intergroup conflicts prevalent in human societies.

Moral Foundations Theory Among Autistic and Neurotypical Children

Morality can help guide behavior and facilitate relationships. Although moral judgments by autistic people are similar to neurotypical individuals, many researchers argue that subtle differences signify deficits in autistic individuals. Moral foundation theory describes moral judgments in terms of differences rather than deficits. The current research, aimed at assessing autistic individuals' moral inclinations using Haidt's framework, was co-designed with autistic community members. Our aim was to describe autistic moral thinking from a strengths-based perspective while acknowledging differences that may pose interpersonal challenges among autistic youth. We assessed 25 autistic and 23 neurotypical children's moral judgments using the Moral Foundations Questionnaire for Kids. We used semi-structured interviews and qualitative analysis with a subset of participants to describe children's moral reasoning. Analyses suggested that autistic and neurotypical children make similar judgments about moral transgressions across all five moral foundations. General linear mixed modeling showed that the greatest predictor of recommending punishment was how bad children deemed moral transgressions to be. We also found a trend that autistic children were more likely to recommend punishment for harmless norms violations than were neurotypical children. Future research could use longitudinal methods to understand the development of moral judgments among autistic and neurotypical children.

Understanding Intergroup Relations in Childhood and Adolescence

There are various theoretical approaches for understanding intergroup biases among children and adolescents. This article focuses on the social identity approach and argues that existing research will benefit by more fully considering the implications of this approach for examining intergroup relations among youngsters. These implications include (a) the importance of self-categorization, (b) the role of self-stereotyping and group identification, (c) the relevance of shared understandings and developing ingroup consensus, and (d) the importance of coordinated action for positive and negative intergroup relations. These implications of the social identity approach suggest several avenues for investigating children’s and adolescents’ intergroup relations that have not been fully appreciated in the existing literature. However, there are also limitations to the social identity approach for the developmental understanding and some of these are discussed.

Toddlers draw broad negative inferences from wrongdoers' moral violations

By 2 y of age, children possess expectations about several different moral principles. Building on these results, we asked whether children who observed a wrongdoer violate a principle would draw negative inferences from this violation about how the wrongdoer was likely to behave in other contexts. In four experiments, 25-mo-old toddlers (n = 152) first saw a wrongdoer harm a protagonist. When toddlers judged the wrongdoer's behavior to violate the principle of ingroup support or harm avoidance, they did not find it unexpected if the wrongdoer next violated the principle of fairness by dividing resources unfairly between two other protagonists (Exps. 2 and 3), but they did find it unexpected if the wrongdoer next acted generously by giving another protagonist most of a resource to be shared between them (Exp. 4). When toddlers did not construe the wrongdoer's harmful behavior as a moral violation, these responses reversed: They found it unexpected if the wrongdoer next acted unfairly (Exp. 1) but not if the wrongdoer next acted generously (Exp. 4). Detecting a moral violation thus lowered toddlers' assessment of the wrongdoer's moral character and brought down their expectations concerning the likelihood that the wrongdoer would perform: 1) obligatory actions required by other principles and 2) supererogatory or virtuous actions not required by the principles. Together, these findings expand our understanding of how young children evaluate others' moral characters, and they reveal how these evaluations, in turn, enable children to form sophisticated expectations about others' behavior in new contexts.

Racial Awareness and Bias Begin Early: Developmental Entry Points, Challenges, and a Call to Action

Overt expressions of racial intolerance have surged precipitously. The dramatic uptick in hate crimes and hate speech is not lost on young children. But how, and how early, do children become aware of racial bias? And when do their own views of themselves and others become infused with racial bias? This article opens with a brief overview of the existing experimental evidence documenting developmental entry points of racial bias in infants and young children and how it unfolds. The article then goes on to identify gaps in the extant research and outlines three steps to narrow them. By bringing together what we know and what remains unknown, the goal is to provide a springboard, motivating a more comprehensive psychological-science framework that illuminates early steps in the acquisition of racial bias. If we are to interrupt race bias at its inception and diminish its effects, then we must build strong cross-disciplinary bridges that span the psychological and related social sciences to shed light on the pressing issues facing our nation's young children and their families.

Intuitive sociology

How do humans intuitively understand the structure of their society? How should psychologists study people's commonsense understanding of societal structure? The present chapter seeks to address both of these questions by describing the domain of "intuitive sociology." Drawing primarily from empirical research focused on how young children represent and reason about social groups, we propose that intuitive sociology consists of three core phenomena: social types (the identification of relevant groups and their attributes); social value (the worth of different groups); and social norms (shared expectations for how groups ought to be). After articulating each component of intuitive sociology, we end the chapter by considering both the emergence of intuitive sociology in infancy as well as transitions from intuitive to reflective representations of sociology later in life.

Shrunken Social Brains? A Minimal Model of the Role of Social Interaction in Neural Complexity

The social brain hypothesis proposes that enlarged brains have evolved in response to the increasing cognitive demands that complex social life in larger groups places on primates and other mammals. However, this reasoning can be challenged by evidence that brain size has decreased in the evolutionary transitions from solitary to social larger groups in the case of Neolithic humans and some eusocial insects. Different hypotheses can be identified in the literature to explain this reduction in brain size. We evaluate some of them from the perspective of recent approaches to cognitive science, which support the idea that the basis of cognition can span over brain, body, and environment. Here we show through a minimal cognitive model using an evolutionary robotics methodology that the neural complexity, in terms of neural entropy and degrees of freedom of neural activity, of smaller-brained agents evolved in social interaction is comparable to the neural complexity of larger-brained agents evolved in solitary conditions. The nonlinear time series analysis of agents' neural activity reveals that the decoupled smaller neural network is intrinsically lower dimensional than the decoupled larger neural network. However, when smaller-brained agents are interacting, their actual neural complexity goes beyond its intrinsic limits achieving results comparable to those obtained by larger-brained solitary agents. This suggests that the smaller-brained agents are able to enhance their neural complexity through social interaction, thereby offsetting the reduced brain size.

Origins of homophily: Infants expect people with shared preferences to affiliate

Homophily structures human social networks: people tend to seek out or be attracted to those who share their preferences or values, and to generally expect social connections between similar people. Here, we probe the nature and extent of infants' homophilic thinking by asking whether infants can use information about other people's shared preferences in the absence of other socially relevant behaviors (e.g., their proximity or joint attention) to infer their affiliation. To do so, we present infants with scenarios in which two people either share a preference or have opposing preferences while varying (across studies) the degree to which those people engage in other socially relevant behaviors. We show that by 14 months of age, infants demonstrate clear inferences of homophily: they expect two people with a shared preference to be more likely to affiliate than two people without such similarity, even in the absence of other social behaviors that signal friendship. Although such cognition begins to emerge by 6-months, younger infants' inferences are bolstered by social behaviors that signal friendship. Thus, an abstract understanding that homophily guides third-party affiliation has its roots in the second year of life, and potentially earlier.

The power of allies: Infants' expectations of social obligations during intergroup conflict

Many species of animals form social allegiances to enhance survival. Across disciplines, researchers have suggested that allegiances form to facilitate within group cooperation and defend each other against rival groups. Here, we explore humans' reasoning about social allegiances and obligations beginning in infancy, long before they have experience with intergroup conflict. In Experiments 1 and 2, we demonstrate that infants (17-19 months, and 9-13 months, respectively) expect a social ally to intervene and provide aid during an episode of intergroup conflict. Experiment 3 conceptually replicated the results of Experiments 1 and 2. Together, this set of experiments reveals that humans' understanding of social obligation and loyalty may be innate, and supported by infants' naïve sociology.

Infants preferentially help individuals who label objects conventionally

Recent evidence suggests that infants engage in selective prosocial behavior toward some individuals over others; the ways in which infants are selective can illuminate the origins of prosocial behaviors. Here, we explored selective helping behavior, investigating whether a target recipient's prior adherence to, or defiance of, social conventions affects infants' subsequent likelihood of helping the target individual. 19-month-old infants (N = 120) participated in an interaction with an experimenter who correctly labeled common objects, incorrectly labeled objects, or labeled objects with nonsense English-like labels. Infants' rates of helping were higher when the experimenter adhered to labeling conventions than when she defied labeling conventions by either labeling objects incorrectly or using unfamiliar nonsense labels. The current study provides evidence that infants use information about adhering to conventions to guide their helping behavior. These findings help to document the ways in which infants are selective in their helping behavior as well as possible origins of prosocial obligations toward ingroup members.

Infant expectations of instant or delayed gratification

Choices between immediate gratification and long-term (but larger) gains are prevalent in human life, which is why the decision-making processes to delay gratification have been studied extensively throughout different developmental ages. Children's delay-of-gratification behaviors have been examined in the well-known "marshmallow test," in which 3- to 5-year-olds are given a marshmallow and told by an experimenter that they can eat it immediately or wait for an unspecified duration of time (which can be capped at 15 min) until the experimenter returns so that they can receive another marshmallow. Children's wait time has been viewed as a good indicator of their later development. Here we show that a group of 22-month-old infants (N = 32) already held expectations about others' choices in a violation-of-expectation looking-time task modeled after the marshmallow test. The infants expected an agent to defer gratification based on a speaker's promise of the second marshmallow available in the future, but to eat the currently attainable marshmallow when the speaker made no such promise. Our findings indicate an early-emerging understanding of others' choices of delayed or instant gratification and shed new light on the development of delay-of-gratification behaviors.

Social-Structure Learning

Social-structure learning is the process by which social groups are identified on the basis of experience. Building on models of structure learning in other domains, we formalize this problem within a Bayesian framework. According to this framework, the probabilistic assignment of individuals to groups is computed by combining information about individuals with prior beliefs about group structure. Experiments with adults and children provide support for this framework, ruling out alternative accounts based on dyadic similarity. More broadly, we highlight the implications of social-structure learning for intergroup cognition, stereotype updating, and coalition formation.

Young children and adults associate social power with indifference to others' needs

In hierarchical societies, what do we expect from people at the top? Early in life, children use horizontal relationships (e.g., affiliation) to predict selectivity in others' prosocial behavior. But it is unknown whether children also view asymmetries in prosocial behavior as characteristic of vertical relationships (e.g., differences in social power). In two experiments, we investigated 4- to 7-year-old children's and adults' (N = 192) intuitions about links among relative authority status, helpful action, and unhelpful inaction. In Experiment 1, participants at all ages viewed a character who chose not to help another person as holding a position of authority over them; participants also viewed this unhelpful character as being less nice than the person in need. However, no age group made consistent inferences about the relative authority of a helper and a helpee. In Experiment 2, children had mixed intuitions when separately predicting whether high- and low-authority characters would be helpful in the future. However, older children and adults consistently indicated that a subordinate would be more likely than an authority to help a third party. These findings establish that children's social theories include expectations for links between power and prosociality by at least the preschool years. Whereas some judgments in this domain are stable from 4 years of age onward, others emerge gradually. Whether consistent responses occurred early or only later in development, however, all measures converged on a single intuition: People more easily associate authority with indifference to others' needs.

Is participation in high-status culture a signal of trustworthiness?

Trust is essential for social interactions, cooperation and social order. Research has shown that social status and common group memberships are important determinants of receiving and reciprocating trust. However, social status and group membership can coincide or diverge–with potentially different effects. Our study contributes to the existing literature on the role of status and group membership by testing two separate trust-generating mechanisms against each other. We examine if individuals tend to place trust in high-status groups (irrespective of their own group membership) or, rather, if they tend to trust others with whom they share a common group membership. We assume that status group membership is signalled by cultural (musical) taste. This operationalization follows the theoretical reasoning of Bourdieu who argues that it is, above all, musical taste that classifies persons of different status. By demonstrating their “legitimate” cultural taste, upper-class members distinguish themselves from the middle and lower classes and signal their social status, thereby creating awe, respect and an air of trustworthiness. We report evidence from online experiments with incentivized trust games, which enable us to separate the two trust-generating mechanisms. We find no evidence that persons with “legitimate” tastes are generally trusted more. Instead, our results clearly demonstrate ingroup favouritism towards persons with a similar taste. Participants place more trust in members of their own group and expect them to be more trustworthy. In other words: members of taste-based groups trust each other more than members of different-taste-based groups. Interestingly, this group-based trust is not always justified inasmuch as received trust is not necessarily reciprocated more strongly by own group members. This suggests that ingroup favouritism is, at least in part, driven by false beliefs.

Groups as moral boundaries: A developmental perspective

In this chapter we present the perspective that social groups serve as moral boundaries. Social groups establish the bounds within which people hold moral obligations toward one another. The belief that people are morally obligated toward fellow social group members, but not toward members of other groups, is an early-emerging feature of human cognition, arising out of domain-general processes in conceptual development. We review evidence that supports this account from the adult and child moral cognition literature, and we describe the developmental processes by which people come to view social groups as shaping moral obligation. We conclude with suggestions about how this account can inform the study of social cognitive development more broadly, as well as how it can be used to promote positive moral socialization.

First steps toward an understanding of procedural fairness

In four experiments, we tested whether 20-month-old infants are sensitive to violations of procedural impartiality. Participants were shown videos in which help was provided in two different ways. A main character provided help to two other agents either impartially, by helping them at the same time, or in a biased way, by helping one agent almost immediately while the other after a longer delay. Infants looked reliably longer at the biased than at the unbiased help scenarios despite the fact that in both scenarios help was provided to each beneficiary. This suggests that human infants can attend to departures from impartiality and, in their second year, they already show an initial understanding of procedural fairness.

Intuitive theories inform children's beliefs about intergroup obligation

In addition to emerging from children's direct experiences with collaborative partners and groups, children's beliefs about obligation also arise from a process of intuitive theory-building in early childhood. On this account, it is possible for at least some of children's beliefs to emerge in the absence of specific experiences where obligations are held among fellow members of a group “we.”

The Development of Social Categorization

Social categorization is a universal mechanism for making sense of a vast social world with roots in perceptual, conceptual, and social systems. These systems emerge strikingly early in life and undergo important developmental changes across childhood. The development of social categorization entails identifying which ways of classifying people are culturally meaningful, how these categories might be used to predict, explain, and evaluate the behavior of other people, and how one's own identity relates to these systems of categorization and representation. Social categorization can help children simplify and understand their social environment but has detrimental consequences in the forms of stereotyping, prejudice, and discrimination. Thus, understanding how social categorization develops is a central problem for the cognitive, social, and developmental sciences. This review details the multiple developmental processes that underlie this core psychological capacity.