41, p = 0.042) and none in rDLPFC (r = 0.275, p = 0.184). For the adults, however, the correlations were not significant in lDLPFC (r = 0.342, p = 0.253) or in rDLPFC (r = 0.222, p = 0.465). The goal of the present study was to investigate the development of strategic social behavior during childhood and the specific cognitive and neural

mechanisms which give rise to observed age-related changes. Given the importance of late-maturing brain regions such as DLPFC in implementing fair behavior (Sanfey et al., GSK1349572 manufacturer 2003, Knoch et al., 2006 and Spitzer et al., 2007), we hypothesized that these areas would also be critically involved in bringing about increased social strategic behavior as a function of improved impulse control with increasing age. We used two game-theoretical-based

paradigms derived from economics that differed only in their demands for strategic behavior. In both games, proposers could decide on how to split their endowment with the responders, but in one game (the Ultimatum Game, UG) they could incur punishment in the form of the responder rejecting the offer, and in the other game (the Dictator Game, DG) no such punishment option was available to the responder. We observed that when rejection of the offers was possible, proposers were willing to share more than when it was not possible, indicating strategic behavior to avoid punishment. More importantly, however, strategic behavior, operationalized as the difference between offers in UG versus DG, increased with age, which was shown and replicated in two see more independent studies. Crucially, we also observed age-related increases in performance on an impulse control measure (Logan, 1994), which, in turn, also correlated with the degree of strategic behavior. No age differences could be found on other relevant tasks included in an extensive battery of tests, such as social preferences of fairness, beliefs, and simulations of

the responder’s behavior or risk preferences. Furthermore, individual differences in strategic behavior did not show any significant correlations with specific social skills such as empathy or theory of mind, or general cognitive skills such as fluid intelligence. These findings provide strong behavioral evidence in support of the from hypothesis that there is an observed age-related increase in strategic social behavior in social exchange tasks during childhood that arises out of improved behavioral control abilities. Further support for this hypothesis is provided by analysis of the responder behavior in Study 1. Younger children were more willing to accept unfair offers than older children, despite comparable ratings of how fair and unfair these offers were considered. Thus, even though fairness norms of the younger children are comparable to those of older children, acting on them when confronted with valuable and, therefore, tempting options seems more difficult for younger children.