Reciprocity norms are an integral part of social support and such norms require sophisticated social cognition (Fujisawa, Katsukake & Hasegawa, 2008). Therefore, the understanding and application of early reciprocity norms provides useful insights into aspects of children's developing social cognition. The present study investigates the degree to which reciprocity norms operate in US preschoolers. To do this, we look at the distinction between need based mutual responsiveness and exchange based direct reciprocity norms in children. The dimensions explored in this study, timing of return, the effect cost of original benefit has on the likelihood of a return and the need versus the non-need based nature of return, have not been explored in the developmental literature.

Using a focal observation video technique, we measured the naturally occurring exchange of benefits between 18 four year olds at the Columbia University Medical Center Nursery School. We found support for some emerging dimensions of direct reciprocity norms. We predicted that the time between an initial benefit and a non-need based return should be shorter than the time between an initial benefit and a need based return. While we did not find support for a difference between the timing of need and non-need based returns, the average timing for both was only, M=5.80 minutes. We also predicted the presence of more non-need based returns than need based returns. Our finding that 83.3% of the returns were non-need based supports this hypothesis. Finally, we predicted direct reciprocity norms should be more apparent when high cost benefits are given than when low cost benefits are given as children may feel more compelled to provide a return for a benefit they perceive required effort or sacrifice. Our data supports this hypothesis by demonstrating that children are significantly more likely to provide a return for a high cost benefit rather than for a low cost benefit. Together, these findings imply children can measure benefits they receive, are aware of whether return is necessary, and utilize tools around them, such as toys and their own ability to help to create non-need based returns in a short amount of time.