Distinct Inhibitory-Control Processes Underlie Children's Judgments of Fairness.

We examined how 5- to 8-year-olds (N = 51; Mage = 83 months; 27 female, 24 male; 69% White, 12% Black/African American, 8% Asian/Asian American, 6% Hispanic, 6% not reported) and adults (N = 18; Mage = 20.13 years; 11 female, 7 male) accepted or rejected different distributions of resources between themselves and others. We used a reach-tracking method to track finger movement in 3D space over time. This allowed us to dissociate two inhibitory processes. One involved pausing motor responses to detect conflict between observed information and how participants thought resources should be divided; the other involved resolving the conflict between the response and the alternative. Reasoning about disadvantageous inequities involved more of the first system, and this was stable across development. Reasoning about advantageous inequities involved more of the second system and showed more of a developmental progression. Generally, reach tracking offers an on-line measure of inhibitory control for the study of cognition.

Rectifying inequities in resource collection in young children.

Numerous studies have documented children's understanding of fairness through their ability to rectify inequities when distributing resources to others. Understanding fairness, however, involves more than just applying norms of equity when distributing resources. Children must also navigate situations in which resources are collected from them for a common good. The developmental origins and the trajectory of equitable resource collection are understudied in the literature on children's prosocial behavior. Experiment 1 presented 4- to 8-year-olds (N = 130) with characters who started with different amounts of resources that were available for both personal use and a group project in school. Participants were asked how a teacher should fairly collect resources from the two characters, contrasting the teacher taking the same amount of resources from each individual (preserving the inequity) or leaving each individual with the same amount of resources (rectifying the inequity). Four- and 5-year-olds responded randomly; 6- to 8-year-olds preferred to rectify the inequity. Experiment 2 reproduced this finding on a new group of 5- to 7-year-olds (N = 69), eliciting justifications for their choice. Justifications in terms of fairness related to equitable choices. Experiment 3 reproduced this finding again in a new group of 5- to 7-year-olds (N = 77), contrasting children's preference for equitable resource collection with that of resource distribution. Children were more likely to rectify an inequity when collecting resources than when distributing resources to individuals who started with an inequity. This difference was driven more by the younger children in the sample. We discuss potential mechanisms for these findings in terms of children's developing concepts of fairness. RESEARCH HIGHLIGHTS: Across three experiments, children developed preferences for equitable collection of resources by age 6. Preferences for equitable resource collection were more likely to be justified by appealing to concepts of fairness. Although preferences for equitable resource collection emerged slightly before equitable resource distribution, these data suggest children develop a unified mechanism for prosocial resource allocation.