Intention-based evaluations of distributive actions by 4-month-olds

Core Moral Concepts and the Sense of Fairness in Human Infants

We review recent experimental studies relevant to assess the proposal that human infants possess a sense of fairness that relies on sociomoral knowledge. We propose that this knowledge may include a core concept of justice with four foundational aspects: impartiality, agency, obligatoriness and conflicting claims. Infants' and toddlers' looking times, manual preferences and spontaneous actions provide some evidence for the first three features. Very early-emerging sociomoral evaluations and expectations about resource distributions show that infants process morally relevant information about distributors and recipients, suggesting that they are sensitive to the agency and impartiality constraints. Early evaluations appear to be linked to third-party expressions of praise or admonishment and to the deliverance of rewards and punishment, providing initial support for the obligatoriness constraint. More work is needed to investigate the sensitivity to conflicting claims, to assess the universality of early emerging evaluation skills and to show how core concepts relate to the development of explicit judgments and beliefs about duties and rights.

Infants' Social Evaluation of Helpers and Hinderers: A Large-Scale, Multi-Lab, Coordinated Replication Study

Evaluating whether someone's behavior is praiseworthy or blameworthy is a fundamental human trait. A seminal study by Hamlin and colleagues in 2007 suggested that the ability to form social evaluations based on third-party interactions emerges within the first year of life: infants preferred a character who helped, over hindered, another who tried but failed to climb a hill. This sparked a new line of inquiry into the origins of social evaluations; however, replication attempts have yielded mixed results. We present a preregistered, multi-laboratory, standardized study aimed at replicating infants' preference for Helpers over Hinderers. We intended to (1) provide a precise estimate of the effect size of infants' preference for Helpers over Hinderers, and (2) determine the degree to which preferences are based on social information. Using the ManyBabies framework for big team-based science, we tested 1018 infants (567 included, 5.5-10.5 months) from 37 labs across five continents. Overall, 49.34% of infants preferred Helpers over Hinderers in the social condition, and 55.85% preferred characters who pushed up, versus down, an inanimate object in the nonsocial condition; neither proportion differed from chance or from each other. This study provides evidence against infants' prosocial preferences in the hill paradigm, suggesting the effect size is weaker, absent, and/or develops later than previously estimated. As the first of its kind, this study serves as a proof-of-concept for using active behavioral measures (e.g., manual choice) in large-scale, multi-lab projects studying infants.

Age differences in prosociality across the adult lifespan: A meta-analysis

Lifespan developmental theories and research suggest a positive effect of adult age on prosociality. However, this effect lacks consistency, with many studies excluding the period of midlife. This study summarized cross-sectional studies on adult age and prosociality, combining 120 (independent) samples (n = 103,829) in a lifespan meta-analysis approach. Linear and quadratic age effects on prosociality were analyzed, as well as comparisons between younger, middle-aged, and older adults. Prosociality was assessed via behavioral measures and self-reports. In both these domains, results indicated small linear age effects and higher prosociality in older compared to younger adults, supporting the hypothesis of increased prosociality in older age. Additionally, leveraging open data sets (64/120 independent samples), predominantly unpublished, we found some evidence for potential quadratic age effects on behavioral prosociality: Middle-aged adults exhibited higher behavioral and self-reported prosociality than younger adults, but no differences between middle-aged and older adults were observed. This meta-analysis offers new perspectives on age trajectories of prosociality, suggesting midlife as a potentially important phase of pronounced prosociality.

Evaluations of aggressive chasing interactions by 7-month-old infants

Recent theories of socio-moral development assume that humans evolved a capacity to evaluate others' social actions in different kinds of interactions. Prior infant studies found both reaching and visual preferences for the prosocial over the antisocial agents. However, whether the attribution of either positive or negative valence to agents' actions involved in an aggressive chasing interaction can be inferred by both reaching behaviors and visual attention deployment (i.e., disengagement of visual attention) is still an open question. Here we presented 7-month-old infants (N = 92) with events displaying an aggressive chasing interaction. By using preferential reaching and an attentional task (i.e., overlap paradigm), we assessed whether and how infants evaluate aggressive chasing interactions. The results demonstrated that young infants prefer to reach the victim over the aggressor, but neither agent affects visual attention. Moreover, such reaching preferences emerged only when dynamic cues and emotional face-like features were congruent with agents' social roles. Overall, these findings suggested that infants' evaluations of aggressive interactions are based on infants' sensitivity to some kinematic cues that characterized agents' actions and, especially, to the congruency between such motions and the face-like emotional expressions of the agents.

Questioning the nature and origins of the "social agent" concept

Spelke posits that the concept of "social agent," who performs object-directed actions to fulfill social goals, is the first noncore concept that infants acquire as they begin to learn their native language. We question this proposal on empirical grounds and theoretical grounds, and propose instead that the representation of object-mediated interactions may be supported by a dedicated prelinguistic mechanism.

Evidence for core social goal understanding (and, perhaps, core morality) in preverbal infants

Spelke's What Babies Know masterfully describes infants' impressive repertoire of core cognitive concepts, from which the suite of human knowledge is eventually built. The current commentary argues for the existence of a core concept that Spelke claims preverbal infants lack: social goal. Core social goal concepts, operative extremely early in human development, underlie infants' basic abilities to interpret and evaluate entities within the moral world; such abilities support claims for a core moral domain.

Toddlers Prefer Agents Who Help Those Facing Harder Tasks

Capacities to understand and evaluate others' actions are fundamental to human social life. Infants and toddlers are sensitive to the costs of others' actions, infer others' values from the costs of the actions they take, and prefer those who help others to those who hinder them, but it is largely unknown whether and how cost considerations inform early understanding of third-party prosocial actions. In three experiments (N = 94), we asked whether 16-month-old toddlers value agents who selectively help those who need it most. Presented with two agents who attempted two tasks, toddlers preferentially looked to and touched someone who helped the agent in greater need, both when one agent's task required more effort and when the tasks were the same but one agent was weaker. These results provide evidence that toddlers engage in need-based evaluations of helping, applying their understanding of action utilities to their social evaluations.

Common and distinct equity preferences in children and adults

Fairness plays a crucial role in children's social life and has garnered considerable attention. However, previous research and theories primarily examined the development of children's fairness behaviors in the conflict between self-interest motivation and fairness-complying motivation, neglecting the influence of advantage-seeking motivation. Moreover, despite the well-established role of gain/loss frame in human decision-making, it remains largely unclear whether the framing effect modulates fairness behaviors in children. It was hypothesized that children would exhibit advantage-seeking motivation resulting in more selfish behaviors in the loss context. To examine the hypothesis, we combined an adapted dictator game and computational modeling to investigate various motivations underlying fairness behaviors of children in both loss and gain contexts and to explore the developmental directions by contrasting children and adults. In addition, the current design enabled the dissociation between fairness knowledge and behaviors by asking participants to decide for themselves (the first-party role) or for others (the third-party role). This study recruited a total of 34 children (9-10 years, Mage = 9.82, SDage = 0.38, 16 females) and 31 college students (Mage = 19.81, SDage = 1.40, 17 females). The behavioral results indicated that children behaved more selfishly in first-party and more fairly in third-party than adults, without any significant framing effects. The computational results revealed that both children and adults exhibited aversion to advantageous and disadvantageous inequity in third-party. However, they showed distinct preferences for advantageous inequity in first-party, with advantage-seeking preferences among children and aversion to advantageous inequity among adults. These findings contribute to a deeper understanding of children's social preferences and their developmental directions.

The science of justice: The neuropsychology of social punishment

The social punishment (SP) of norm violations has received much attention across multiple disciplines. However, current models of SP fail to consider the role of motivational processes, and none can explain the observed behavioral and neuropsychological differences between the two recognized forms of SP: second-party punishment (2PP) and third-party punishment (3PP). After reviewing the literature giving rise to the current models of SP, we propose a unified model of SP which integrates general psychological descriptions of decision-making as a confluence of affect, cognition, and motivation, with evidence that SP is driven by two main factors: the amount of harm (assessed primarily in the salience network) and the norm violator's intention (assessed primarily in the default-mode and central-executive networks). We posit that motivational differences between 2PP and 3PP, articulated in mesocorticolimbic pathways, impact final SP by differentially impacting the assessments of harm and intention done in these domain-general large-scale networks. This new model will lead to a better understanding of SP, which might even improve forensic, procedural, and substantive legal practices.

Evaluations of pro-environmental behaviors by 7-month-old infants

Environmental morality is the foundation of a sustainable future, yet its ontogenetic origin remains unknown. In the present study, we asked whether 7-month-olds have a sense of 'environmental morality'. Infants' evaluations of two pro-environmental actions were assessed in both visual and reaching preferential tasks. In Experiment 1, the overt behavior of protecting (i.e., collecting artificial objects spread on a lawn) was compared with the action of harming the environment (i.e., by disregarding the objects). In Experiment 2, the covert behavior of protecting the environment (i.e., maintaining artificial objects inside a container) was compared with the action of harming the environment (i.e., littering the artificial objects on a lawn). The results showed infants' reaching preference for the agent who performed overt pro-environmental actions (Experiment 1), and no preference for the agent who performed covert pro-environmental actions (Experiment 2). These findings reveal a rudimentary ecological sense and suggest that infants require different abilities to evaluate overt impact-oriented and covert intend-oriented pro-environmental behaviors.