Carsten K W De Dreu

• PhD
• Professor (Full) at Leiden University

Behavioural ecologies in themselves can create variation in fitness interdependencies among individuals, and hence modulate the functionality of invoking historical myths. We develop this possibility for the case where coalitions form to attack and exploit enemies, or to defend and protect against hostile out-groups. We propose that invoking histor...

When defending against hostile enemies, individual group members can benefit from others staying in the group and fighting. However, individuals themselves may be better off by leaving the group and avoiding the personal risks associated with fighting. While fleeing is indeed commonly observed, when and why defenders fight or flee remains poorly un...

To avoid exploitation by defectors, people can use past experiences with others when deciding to cooperate or not (‘private information’). Alternatively, people can derive others’ reputation from ‘public’ information provided by individuals within the social network. However, public information may be aligned or misaligned with one’s own private ex...

Like other group-living species, humans often cooperate more with an in-group member than with out-group members and strangers. Greater in-group favoritism should imply that people also compete less with in-group members than with out-group members and strangers. However, in situations where people could invest to take other’s resources and invest...

By examining the shared neuro-cognitive correlates of curiosity and creativity, we better understand the brain basis of creativity. However, by only examining shared components, important neuro-cognitive correlates are overlooked. Here, we argue that any comprehensive brain model of creativity should consider multiple cognitive processes and, along...

The functioning of groups and societies requires that individuals cooperate on public goods such as healthcare and state defense. More often than not, individuals face multiple public goods and must choose on which to cooperate, if at all. Such decisions can be difficult when public goods are attractive on one dimension (e.g., being “efficient” in...

In theory, it can be strategically advantageous for competitors to make themselves unpredictable to their opponents, for example, by variably mixing hostility and friendliness. Empirically, it remains open whether and how competitors make themselves unpredictable, why they do so, and how this conditions conflict dynamics and outcomes. We examine th...

We take issue with Glowacki's assumption that intergroup relations are characterized by positive-sum interactions and suggest to include negative-sum interactions, and between-group independence. As such, peace may be better defined as the absence of negative-sum interactions. Rather than being a consequence of cooperation, peace emerges as a neces...

Cooperation is more likely when individuals can choose their interaction partner. However, partner choice may be detrimental in unequal societies, in which individuals differ in available resources and productivity, and thus in their attractiveness as interaction partners. Here we experimentally examine this conjecture in a repeated public goods ga...

Leaders can launch hostile attacks on out-groups and organize in-group defence. Whether groups settle the conflict in their favour depends, however, on whether followers align with leader’s initiatives. Yet how leader and followers coordinate during intergroup conflict remains unknown. Participants in small groups elected a leader and made costly c...

Humans operate in groups that are oftentimes nested in multilayered collectives such as work units within departments and companies, neighborhoods within cities, and regions within nation states. With psychological science mostly focusing on proximate reasons for individuals to join existing groups and how existing groups function, we still poorly...

We take issue with Glowacki’s assumption that intergroup relations are characterized by positive-sum interactions and suggest to include negative-sum interactions, and between-group independence. As such, peace may be better defined as the absence of negative-sum interactions. Rather than being a consequence of cooperation, peace emerges as a neces...

Globalizing economies and long-distance trade rely on individuals from different cultural groups to negotiate agreement on what to give and take. In such settings, individuals often lack insight into what interaction partners deem fair and appropriate, potentially seeding misunderstandings, frustration, and conflict. Here, we examine how individual...

Peer punishment can help groups to establish collectively beneficial public goods. However, when humans condition punishment on other factors than poor contribution, punishment can become ineffective and group cooperation deteriorates. Here we show that this happens in pluriform groups where members have different socio-demographic characteristics....

Humans work together in groups to tackle shared problems and contribute to local club goods that benefit other group members. Whereas benefits from club goods remain group bound, groups are often nested in overarching collectives that face shared problems like pandemics or climate change. Such challenges require individuals to cooperate across grou...

Individuals often face dilemmas in which non-cooperation serves their self-interest and cooperation favors society at large. Cooperation is often considered the moral choice because it creates equality and fairness among citizens. Accordingly, individuals whose political ideology attaches greater value to equality than to agency and self-reliance s...

In a globalizing world, conflict between citizens and foreigners hinders cooperation and hampers how well the global community can tackle shared problems. Here we study conflict between citizens and foreigners and find that people substantially misperceive how competitive foreigners are. Citizens (from 51 countries; N = 12,863; 656,274 decisions) i...

Intergroup conflict profoundly affects the welfare of groups and can deteriorate intergroup relations long after the conflict is over. Here, we experimentally investigate how the experience of an intergroup conflict influences the ability of groups to establish cooperation after conflict. We induced conflict by using a repeated attacker-defender ga...

Human society operates on large-scale cooperation. However, individual differences in cooperativeness and incentives to free-ride on others' cooperation make large-scale cooperation fragile and can lead to reduced social-welfare. Thus, how individual cooperation spreads through human social networks remains puzzling from ecological, evolutionary an...

Across vertebrate species, intergroup conflict confronts individuals with a tension between group interests best served by participation in conflict and personal interest best served by not participating. Here, we identify the neurohormone oxytocin as pivotal to the neurobiological regulation of this tension in distinctly different group-living ver...

Although uniquely destructive and wasteful, intergroup conflict and warfare are not confined to humans. They are seen across a range of group-living species, from social insects, fishes and birds to mammals, including nonhuman primates. With its unique collection of theory, research and review contributions from biology, anthropology and economics,...

Peaceful coexistence and trade among human groups can be fragile and intergroup relations frequently transition to violent exchange and conflict. Here we specify how exogenous changes in groups' environment and ensuing carrying-capacity stress can increase individual participation in intergroup conflict, and out-group aggression in particular. In t...

Attempts at predatory capture may provoke a defensive response that reduces the very value of the predated resource. We provide a game-theoretic analysis of simultaneous-move, two-player Attacker-Defender games that model such interactions. When initial endowments are equal, Attackers win about a third of such games in equilibrium. Under power disp...

Across vertebrate species, intergroup conflict confronts individuals with a tension between group interests best served by participation in conflict and personal interest best served by not participating. Here, we identify the neurohormone oxytocin as pivotal to the neurobiological regulation of this tension in distinctly different group-living ver...

Helping other people can entail risks for the helper. For example, when treating infectious patients, medical volunteers risk their own health. In such situations, decisions to help should depend on the individual’s valuation of others’ well-being (social preferences) and the degree of personal risk the individual finds acceptable (risk preferences...

Intergroup conflict can be modeled as a two-level game of strategy, in which pro-sociality can take the form of trust and cooperation within groups or between groups. We review recent work, from our own laboratory and that of others, that show how biological and socio-cultural mechanisms that promote pro-social preferences and beliefs create in-gro...

Humans differ in their preferences for personal rewards, fairness, and others' welfare. Such social preferences predict trust, public goods provision, and mutual gains bargaining, and have been linked to neural activity in regions involved in reward computation, cognitive control, and perspective taking. Although shaped by culture, social preferenc...

Group discussion often becomes one-sided and confirmatory, with poor decisions as the unfortunate outcome. Here we examine whether intergroup competition amplifies or mitigates effects of individual versus team reward on information sharing biases and group decision quality. Individuals ( N = 309) in 103 interacting groups were given private inform...

Political conflicts often revolve around changing versus defending a status quo . We propose to capture the dynamics between proponents and opponents of political change in terms of an asymmetric game of attack and defence with its equilibrium in mixed strategies. Formal analyses generate predictions about effort expended on revising and protecting...

Humans establish public goods to provide for shared needs like safety or healthcare. Yet, public goods rely on cooperation which can break down because of free-riding incentives. Previous research extensively investigated how groups solve this free-rider problem but ignored another challenge to public goods provision. Namely, some individuals do no...

Experimental games model situations in which the future outcomes of individuals and groups depend on their own choices and on those of other (groups of) individuals. Games are a powerful tool to identify the neural and psychological mechanisms underlying interpersonal and group cooperation and coordination. Here we discuss recent developments in ho...

Ingroup favoritism and discrimination against outgroups are pervasive in social interactions. To uncover the cognitive processes underlying generosity towards in- and outgroup members, we employ eye-tracking in two pre registered studies. We replicate the well-established ingroup favoritism effect and uncover that ingroup compared to outgroup decis...

Compared with working alone, interacting in groups can increase dishonesty and give rise to collaborative cheating—the joint violation of honesty. At the same time, collaborative cheating emerges some but not all of the time, even when dishonesty is not sanctioned and economically rational. Here, we address this conundrum. We show that people diffe...

Individuals immersed in groups sometimes lose their individuality, take risks they would normally avoid and approach outsiders with unprovoked hostility. In this study, we identified within-group neural synchronization in the right dorsolateral prefrontal cortex (rDLPFC) and the right temporoparietal junction (rTPJ) as a candidate mechanism underly...

As colleagues and collaborators, we reflect on the work and legacy of Peter Carnevale, currently professor at the University of Southern California, and recipient of the 2002 Jeffrey Z. Rubin Theory‐to‐Practice Award of the International Association for Conflict Management (IACM). We review Carnevale’s main contributions, including his work on time...

Peaceful intergroup relations deteriorate when individuals engage in parochial cooperation and parochial competition. To understand when and why intergroup relations change from peaceful to violent, we present a theoretical framework mapping out the different interdependence structures between groups. According to this framework, cooperation can le...

Helping others can entail risks. Doctors that treat infectious patients may risk their own health, intervening in a fight can lead to injury, and organ donations can lead to medical complications. When helping others comes with a risk to oneself, decisions depend on the individual’s valuation of others’ well-being (social preferences) and the degre...

Competitions are part and parcel of daily life and require people to invest time and energy to gain advantage over others and to avoid (the risk of) falling behind. Whereas the behavioral mechanisms underlying competition are well documented, its neurocognitive underpinnings remain poorly understood. We addressed this using neuroimaging and computa...

An increasing number of healthy people use methylphenidate, a psychostimulant that increases dopamine and noradrenaline transmission in the brain, to help them focus over extended periods of time. While methylphenidate has been shown to facilitate some cognitive functions, like focus and distractor-resistance, the same drug might also contribute to...

Ingroup favoritism and discrimination against outgroups are pervasive in socialinteractions. To uncover the cognitive processes underlying generosity towards in- and out-group members, we employ eye-tracking in two pre-registered studies. We replicate the well- established ingroup favoritism effect and uncover that in-group compared to out-group de...

Our target article modeled conflict within and between groups as an asymmetric game of strategy and developed a framework to explain the evolved neurobiological, psychological, and sociocultural mechanisms underlying attack and defense. Twenty-seven commentaries add insights from diverse disciplines, such as animal biology, evolutionary game theory...

Economic games offer an analytic tool to examine strategic decision-making in social interactions. Here we identify four sources of power that can be captured and studied with economic games - asymmetric dependence, the possibility to reduce dependence, the ability to punish and reward, and the use of knowledge and information. We review recent stu...

Significance Using an interdisciplinary experimental approach grounded in behavioral economics and personality psychology, we identify an antisocial personality profile and examine its role across strategic contexts. Antisocial individuals exhibit a specific combination of behaviors and beliefs: they have a high propensity to betray others’ trust a...

Alone and together, climatic changes, population growth, and economic scarcity create shared problems that can be tackled effectively through cooperation and coordination. Perhaps because cooperation is fragile and easily breaks down, societies also provide individual solutions to shared problems, such as privatized healthcare or retirement plannin...

History is rife with examples of the dark side of creativity—ingenious weapons, novel torture practices, and creative terrorist attacks—yet its psychological origins are sparsely addressed and poorly understood. Building on work showing that social threat induces focused thinking as well as aggressive cognitions and readiness to fight, we propose t...

Humans exhibit a remarkable capacity for cooperation among genetically unrelated individuals. Yet, human cooperation is neither universal, nor stable. Instead, cooperation is often bounded to members of particular groups, and such groups endogenously form or break apart. Cooperation networks are parochial and under constant reconfiguration. Here, w...

The eyes are extremely important in communication and can send a multitude of different messages. Someone's pupil size carries significant social information and can reflect different cognitive and affective states that within a social interaction can prove to be particularly meaningful. In 3 studies we investigated the impact of a person's pupil s...

Psychologists have long sought to understand how people experience, think, and communicate about situations. Psychology's protracted journey toward understanding psychological situations recently took a momentous turn toward more rigorous conceptualization and measurement of situational characteristics along multiple dimensions. We provide a select...

Existing findings on the intriguing link between vulnerability to psychopathology and creativity are scattered and inconclusive. Here we report 3 studies (total N = 826) that tested a 2-step solution to the possible relationship between vulnerability to psychopathology and creativity. First, we propose that inclinations toward psychopathologies tha...

Intergroup conflict contributes to human discrimination and violence, but persists because individuals make costly contributions to their group’s fighting capacity. Yet, how group members effectively coordinate their contributions during intergroup conflict remains poorly understood. Here, we examine the role of oxytocin for (the coordination of) c...

When humans compete, they invest energy and effort to injure others and to protect against injury and exploitation. The psychology behind exploiting others and protecting against exploitation is still poorly understood and is addressed here in an incentivized economic contest game in which individuals invested in predatory attack and prey defense....

Conflict can profoundly affect individuals and their groups. Oftentimes, conflict involves a clash between one side seeking change and increased gains through victory, and the other side defending the status quo and protecting against loss and defeat. However, theory and empirical research largely neglected these conflicts between attackers and def...

Intergroup conflict contributes to human discrimination and violence, but persists because individuals make costly contributions to their group's fighting capacity. Yet how groups effectively synchronize their contributions during intergroup conflict remains poorly understood. Here we examine whether the evolutionary ancient neuropeptide oxytocin p...

Significance Trusting others is central for cooperative endeavors to succeed. To decide whether to trust or not, people generally make eye contact. As pupils of interaction partners align, mimicking pupil size helps them to make well-informed trust decisions. How the brain integrates information from the partner and from their own bodily feedback t...

Decision-making groups decide on many numerical issues, which makes them potentially vulnerable to cognitive anchors. In the current study we investigated (1) whether the anchoring-bias operates in groups, (2) under which circumstances group anchoring is more or less likely to occur and (3) which processes underlie the anchoring-bias in groups. In...

People are particularly sensitive to injustice. Accordingly, deeper knowledge regarding the processes that underlie the perception of injustice, and the subsequent decisions to either punish transgressors or compensate victims, is of important social value. By combining a novel decision-making paradigm with functional neuroimaging, we identified sp...

In intergroup settings, humans often contribute to their in-group at a personal cost. Such parochial cooperation benefits the in-group and creates and fuels intergroup conflict when it simultaneously hurts out-groups. Here, we introduce a new game paradigm in which individuals can display universal cooperation (which benefits both in- and out-group...

Human history is shaped by landmark discoveries in science and technology. However, across both time and space the rate of innovation is erratic: Periods of relative inertia alternate with bursts of creative science and rapid cascades of technological innovations. While the origins of the rise and fall in rates of discovery and innovation remain po...

Being observed by others fosters honest behavior. In this study, we examine a very subtle eye signal that may affect participants' tendency to behave honestly: observed pupil size. For this, we use an experimental task that is known to evoke dishonest behavior. Specifically, participants made private predictions for a coin toss and earned a bonus b...

Previous work on the threat-creativity link has mainly used paradigms in which participants had ample time to generate ideas. However, people under imminent threats have limited time to think of, and select, the single best response for actual implementation. In three studies, we examined the effect of imminent threats on the generation and selecti...

We examined how formal organizational diversity policies affect minorities’ leadership-relevant self-perceptions and goals in two experiments. Organizational mission statements were manipulated to reflect policies acknowledging and valuing subgroup differences (Multiculturalism), de-emphasizing subgroup differences while valuing interindividual dif...

Creative cognition is key to human functioning yet the underlying neurobiological mechanisms are sparsely addressed and poorly understood. Here we address the possibility that creative cognition is a function of dopaminergic modulation in fronto-striatal brain circuitries. It is proposed that (i) creative cognition benefits from both flexible and p...

Across species, oxytocin, an evolutionarily ancient neuropeptide, facilitates social communication by attuning individuals to conspecifics' social signals, fostering trust and bonding. The eyes have an important signalling function; and humans use their salient and communicative eyes to intentionally and unintentionally send social signals to other...

Rules, whether in the form of norms, taboos or laws, regulate and coordinate human life. Some rules, however, are arbitrary and adhering to them can be personally costly. Rigidly sticking to such rules can be considered maladaptive. Here, we test whether, at the neurobiological level, (mal)adaptive rule adherence is reduced by oxytocin-a hypothalam...

We investigated the appraisal processes and personality antecedents that regulate people’s attraction to schema-violations - targets and objects that disconfirm schema - and stereotype-based expectancies. In two studies a preference for schema-violations (vs. consistencies) correlated positively with openness to experience, and negatively with the...

Groups can make better decisions than individuals when members cooperatively exchange and integrate their uniquely held information and insights. However, under conformity pressures group members are biased towards exchanging commonly known information, and away from exchanging unique information, thus undermining group decision-making quality. At...

Human groups function because members trust each other and reciprocate cooperative contributions, and reward others’ cooperation and punish their non-cooperation. Here we examined the possibility that such third-party punishment and reward of others’ trust and reciprocation is modulated by oxytocin, a neuropeptide generally involved in social bondi...

Significance Across a range of domains, from group-hunting predators to laboratory groups, companies, and nation states, we find that out-group aggression is less successful because it is more difficult to coordinate than in-group defense. This finding explains why appeals for defending the in-group may be more persuasive than appeals to aggress a...

In dit artikel bespreken we recent onderzoek waaruit blijkt wanneer mensen geneigd zijn om parochiale of universele coöperatie te tonen. Hierbij kijken we met name naar iemands persoonlijke sociale waarde oriëntatie. Daarnaast wordt onderzoek naar vertegenwoordigend onderhandelen uitgebreid besproken, waarin wordt gekeken wat voor invloed een achte...

Group-living animals, humans included, produce vocalizations like screams, growls, laughs, and victory calls. Accurately decoding such emotional vocalizations serves both individual and group functioning, suggesting that (i) vocalizations from in-group members may be privileged, in terms of speed and accuracy of processing, and (ii) such processing...

A contribution to a special issue on Hormones and Human Competition. In intergroup settings, individuals prefer cooperating with their in-group, and sometimes derogate and punish out-groups. Here we replicate earlier work showing that such in-group bounded cooperation is conditioned by oxytocin and extend it by showing that oxytocin-motivated in-gr...

Competitive decision-making may require controlling and calculative mind-sets. We examined this possibility in repeated predator-prey contests by up- or down-regulating the individual's right inferior frontal gyrus (rIFG), a brain region involved in impulse-inhibition and mentalizing. Following brain stimulation, subjects invested as predator or pr...

Although many believe that creativity associates with a vulnerability to psychopathology, research findings are inconsistent. Here we address this possible linkage between risk of psychopathology and creativity in nonclinical samples. We propose that propensity for specific psychopathologies can be linked to basic motivational approach and avoidanc...

Based on the motivated information processing in groups model, we predicted that low personal need for structure (PNS) among team members helps team dynamic decision-making performance on highly ambiguous tasks, but hurts performance on tasks low in ambiguity. In a laboratory experiment involving 22 groups of army cadets performing a command-and-co...

Because intergroup interactions often are mixed-motive rather than strictly zero-sum groups often negotiate settlements that enable both cultures to thrive. Moreover group prosperity rests on in-group love (rather than out-group hate) that emerges also absent intergroup competition or comparison. It follows that cultural group selection (CGS) refle...