Prosocial behaviors are a diverse group of actions that are integral to human social life. In this study, we examined the ability of 18-and 24-month-old infants to engage in three types of other-oriented behaviors, specifically helping, sharing, and comforting. Infants in both age groups engaged in more prosocial behavior on trials in which an unfamiliar adult experimenter required aid (experimental conditions) than on those in which she did not (control conditions) across two of the three prosocial tasks (i.e., helping and sharing). The infants engaged in these behaviors with similar frequency; however, there was no correlation between the tasks. The implications for the construct of prosocial behavior and the presence of a prosocial disposition are discussed.

The development and maintenance of prosocial, other-oriented behaviors has been of considerable recent interest. Though it is clear that prosocial behaviors emerge early and play a uniquely important role in the social lives of humans, there is less consensus regarding the mechanisms that underlie and maintain these fundamental acts. The goal of this paper is to clarify inconsistencies in our understanding of the early emergence and development of prosocial behavior by proposing a taxonomy of prosocial behavior anchored in the social-cognitive constraints that underlie the ability to act on behalf of others. I will argue that within the general domain of prosocial behavior, other-oriented actions can be categorized into three distinct types (helping, sharing, and comforting) that reflect responses to three distinct negative states (instrumental need, unmet material desire, and emotional distress). In support of this proposal, I will demonstrate that the three varieties of prosocial behavior show unique ages of onset, uncorrelated patterns of production, and distinct patterns of individual differences. Importantly, by differentiating specific varieties of prosocial behavior within the general category, we can begin to explain inconsistencies in the past literature and provide a framework for directing future research into the ontogenetic origins of these essential social behaviors.

This study investigates the diversity of early prosocial behavior by examining the ability of ninety-five 2- to 4-year-olds to provide aid to an adult experimenter displaying instrumental need, emotional distress, and material desire. Children provided appropriate aid in response to each of these cues with high consistency over multiple trials. In contrast to the consistency with which the children provided aid within each task, there were no cross-task correlations, and the tendency to respond to each of the cues revealed unique developmental trajectories. Taken together, these results provide preliminary support for the importance of examining the cues to which children are responding and of differentiating between varieties of aid when considering the development of prosocial behavior.

One way to maintain cooperation between unrelated individuals and decrease the chance of providing costly aid to those who will not reciprocate is by selectively helping on the basis of the content of previous interactions. In the present study, we sought to determine whether the earliest instances of human helping behavior show specificity. In three experiments, we found that infants preferred to help an individual who, in a previous interaction, intended to provide a toy over one who did not (Experiment 1) and that infants consider this positive intention even without a positive outcome (Experiment 2). Experiment 3 provided a more detailed examination of the basis of selection, suggesting that infants are not solely avoiding unwilling individuals, but also selectively helping those who have shown a willingness to provide. Taken together, these experiments indicate that early helping behaviors show characteristics of the rich reciprocal relationships observed in adult prosocial behavior.