Eric van Dijk

The Neuropeptide Oxytocin Regulates Parochial Altruism in Intergroup Conflict Among Humans

Oxytocin and Intergroup Conflict Human society is organized into groups, such as those based on nationality or religion, which can lead to intergroup conflicts, with sometimes devastating consequences. Intergroup conflict engages a human behavior termed parochial altruism: For example, a soldier who fights against the enemy at risk to themselves to protect their country is a parochial altruist. De Dreu et al. (p. 1408; see the cover; see the News story by Miller) have discovered a role for oxytocin, a neuropeptide produced in the hypothalamus, in regulating parochial altruism during human intergroup competition and conflict. Oxytocin is already known to play a role in trusting behavior, and naturally occurring genetic variants of the oxytocin receptor exist within the human population. Administration of oxytocin modulated defense-related aggression toward competing groups, but did not affect unprovoked, hateful behavior. Thus, there may be a neurobiological basis for intergroup conflict in humans. A hypothalamic hormone modulates bonding within a group and defense-related aggression between competing groups. Humans regulate intergroup conflict through parochial altruism; they self-sacrifice to contribute to in-group welfare and to aggress against competing out-groups. Parochial altruism has distinct survival functions, and the brain may have evolved to sustain and promote in-group cohesion and effectiveness and to ward off threatening out-groups. Here, we have linked oxytocin, a neuropeptide produced in the hypothalamus, to the regulation of intergroup conflict. In three experiments using double-blind placebo-controlled designs, male participants self-administered oxytocin or placebo and made decisions with financial consequences to themselves, their in-group, and a competing out-group. Results showed that oxytocin drives a “tend and defend” response in that it promoted in-group trust and cooperation, and defensive, but not offensive, aggression toward competing out-groups.

The inaction effect in the psychology of regret

Previous research showed that decisions to act (i.e., actions) produce more regret than decisions not to act (i.e., inactions). This previous research focused on decisions made in isolation and ignored that decisions are often made in response to earlier outcomes. The authors show in 4 experiments that these prior outcomes may promote action and hence make inaction more abnormal. They manipulated information about a prior outcome. As hypothesized, when prior outcomes were positive or absent, people attributed more regret to action than to inaction. However, as predicted and counter to previous research, following negative prior outcomes, more regret was attributed to inaction, a finding that the authors label the inaction effect. Experiment 4, showing differential effects for regret and disappointment, demonstrates the need for emotion-specific predictions.

Changing Brains, Changing Perspectives The Neurocognitive Development of Reciprocity

Adolescence is characterized by the emergence of advanced forms of social perspective taking and significant changes in social behavior. Yet little is known about how changes in social cognition are related to changes in brain function during adolescence. In this study, we investigated the neural correlates of social behavior during three phases of adolescence, carrying out functional magnetic resonance imaging of participants’ brains while they were Player 2 in the Trust Game. We found that with age, adolescents were increasingly sensitive to the perspective of the other player, as indicated by their reciprocal behavior. These advanced forms of social perspective-taking behavior were associated with increased involvement of the left temporo-parietal junction and the right dorsolateral prefrontal cortex. In contrast, young adolescents showed more activity in the anterior medial prefrontal cortex, a region previously associated with self-oriented processing and mentalizing. These findings suggest that the asynchronous development of these neural systems may underlie the shift from thinking about self to thinking about the other.

When Gains Loom Larger Than Losses Reversed Loss Aversion for Small Amounts of Money

Previous research has generally shown that people are loss averse; that is, they weigh losses more heavily than gains. In a series of three experiments, we found that for small outcomes, this pattern is reversed, and gains loom larger than losses. We explain this reversal on the basis of (a) the hedonic principle, which states that individuals are motivated to maximize pleasure and to minimize pain, and (b) the assumption that small losses are more easily discounted cognitively than large losses are.

Decision-induced focusing in social dilemmas : Give-some, keep-some, take-some, and leave-some dilemmas

Previous research on asymmetric social dilemmas has suggested that public good dilemmas evoke different choice behaviors than do resource dilemmas. The authors propose that these differences reflect a differential focus that is dependent on the way decisions are generally presented in the dilemma types. In agreement with this, the results of 2 experimental studies suggest that, in public good dilemmas, group members are less focused on the consequences of their actions for the final outcome distribution when deciding how many endowments they give to the public good than when deciding how many endowments they keep for themselves. In resource dilemmas, group members are less focused on the final outcome distribution when deciding how many endowments they leave in the collective resource than when deciding how many endowments they take.

Dissociable brain networks involved in development of fairness considerations: Understanding intentionality behind unfairness

In this functional magnetic resonance imaging study, we examined developmental changes in the brain regions involved in reactions to unfair allocations. Previous studies on adults suggested that reactions to unfairness are not only affected by the distribution itself but also by the ascribed intentionality of the proposer. In the current study, we employed the mini Ultimatum Game (Falk, Fehr, & Fischbacher, 2003) to examine responder behavior to unfair offers of varying degrees of intentionality. Sixty-eight participants from four age groups (10-, 13-, 15-, and 20-year-olds) carried out the task while fMRI data were acquired. Participants of all ages showed activation in the bilateral insula and dorsal anterior cingulate cortex (dACC) during rejection of unintentional but acceptance of intentional unfair offers. Rejection of unintentional unfair offers further involved increasing activation with age in the temporoparietal junction and the dorsolateral prefrontal cortex. These findings provide evidence for an early developing insula-dACC network involved in detecting personal norm-violations and gradually increasing involvement of temporal and prefrontal brain regions related to intentionality considerations in social reasoning. The results are discussed in light of recent findings on the development of the adolescent social brain network.

What motivates repayment? Neural correlates of reciprocity in the Trust Game

Reciprocity of trust is important for social interaction and depends on individual differences in social value orientation (SVO). Here, we examined the neural correlates of reciprocity by manipulating two factors that influence reciprocal behavior: (1) the risk that the trustor took when trusting and (2) the benefit for the trustee when being trusted. FMRI results showed that anterior Medial Prefrontal Frontal Cortex (aMPFC) was more active when participants defected relative to when participants reciprocated, but was not sensitive to manipulations of risk and benefit or individual differences in SVO. However, activation in the temporal-parietal-junction (rTPJ), bilateral anterior insula and anterior cingulate cortex (ACC) was modulated by individual differences in SVO. In addition, these regions were differentially sensitive to manipulations of risk for the trustor when reciprocating. In contrast, the ACC and the right dorsolateral prefrontal cortex were sensitive to the benefit for the trustee when reciprocating. Together, the results of this study provide more insight in how several brain regions work together when individuals reciprocate trust, by showing how these regions are differentially sensitive to reciprocity motives and perspective-taking.

Less power or powerless? Egocentric empathy gaps and the irony of having little versus no power in social decision making

The authors investigate the effect of power differences and associated expectations in social decision making. Using a modified ultimatum game, the authors show that allocators lower their offers to recipients when the power difference shifts in favor of the allocator. Remarkably, however, when recipients are completely powerless, offers increase. This effect is mediated by a change in framing of the situation: When the opponent is without power, feelings of social responsibility are evoked. On the recipient side, the authors show that recipients do not anticipate these higher outcomes resulting from powerlessness. They prefer more power over less, expecting higher outcomes when they are more powerful, especially when less power entails powerlessness. Results are discussed in relation to empathy gaps and social responsibility.

Commitment and Behavior Change A Meta-Analysis and Critical Review of Commitment-Making Strategies in Environmental Research

Commitment making is commonly regarded as an effective way to promote proenvironmental behaviors. The general idea is that when people commit to a certain behavior, they adhere to their commitment, and this produces long-term behavior change. Although this idea seems promising, the results are mixed. In the current article, the authors investigate whether and why commitment is effective. To do so, the authors first present a meta-analysis of environmental studies containing a commitment manipulation. Then, the authors investigate the psychological constructs that possibly underlie the commitment effect. They conclude that commitment making indeed leads to behavior change in the short- and long term, especially when compared with control conditions. However, a better understanding is needed of the possible underlying mechanisms that guide the commitment effect. The authors see commitment making as a potentially useful technique that could be improved by following up on findings from fundamental research. They provide suggestions for future research and recommendations for improving the effectiveness of commitment-making techniques.

Reactions to group success and failure as a function of identification level: a test of the goal-transformation hypothesis in social dilemmas

This study examined the combined effects of identification level, social value orientation, and feedback on contributions in a public goods dilemma. Previous research has shown that strengthening group identity promotes cooperation. One explanation for this finding is that a strong group identity transforms peoples motives from the personal to the collective level (the goal transformation hypothesis). Evidence for this hypothesis can be found in studies showing that a strong sense of group identity influences proselfs, relative to prosocials, to make larger contributions. In this experiment, we demonstrated that these findings are restricted to situations in which no feedback about a groups performance is provided. When performance feedback is provided, a strong group identity cancels the effects of individual differences in social value orientations. In particular, when a group fails, contributions increase if group identity is salient, but decrease if personal identity is salient, regardless of a persons social value orientation. But when a group succeeds, no differences between group and personal identity are found. These results are discussed in terms of the goal transformation hypothesis.