Social preferences correlate with cortical thickness of the orbito-frontal cortex

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 preferences are relatively stable across time, raising the question whether differences in brain anatomy predict social preferences and their key components-concern for personal outcomes and concern for others' outcomes. Here, we examine this possibility by linking social preferences measured with incentivized economic games to 74 cortical parcels in 194 healthy humans. Neither concerns for personal outcomes nor concerns for the outcomes of others in isolation were related to anatomical differences. However, fitting earlier findings, social preferences positively scaled with cortical thickness in the left olfactory sulcus, a structure in the orbital frontal cortex previously shown to be involved in value-based decision-making. Consistent with work showing that heavier usage corresponds to larger brain volume, findings suggest that pro-social preferences relate to cortical thickness in the left olfactory sulcus because of heavier reliance on the orbital frontal cortex during social decision-making. Keywords: brain anatomy; decision-making; social value orientatio

Political games of attack and defence

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 the status quo, the form and function of false signalling and cheap talk, how power differences impact conflict intensity and the likelihood of status quo revision. Laboratory experiments on the neurocognitive and hormonal foundations of attack and defence reveal that out-of-equilibrium investments in attack emerge because of non-selfish preferences, limited capacity to compute costs and benefits and optimistic beliefs about the chances of winning from one's rival. We conclude with implications for the likelihood of political change and inertia, and discuss the role of ideology in political games of attack and defence. This article is part of the theme issue 'The political brain: neurocognitive and computational mechanisms'. Keywords: cognitive control; contest theory; decision-making; ideology; perspective taking; polarizatio

Learning rules of engagement for social exchange within and between groups

Globalizing economies and long-distance trade rely on individuals from different cul- tural groups to negotiate agreement on what to give and take. In such settings, indi- viduals often lack insight into what interaction partners deem fair and appropriate, potentially seeding misunderstandings, frustration, and conflict. Here, we examine how individuals decipher distinct rules of engagement and adapt their behavior to reach agreements with partners from other cultural groups. Modeling individuals as Bayesian learners with inequality aversion reveals that individuals, in repeated ultimatum bargaining with responders sampled from different groups, can be more generous than needed. While this allows them to reach agreements, it also gives rise to biased beliefs about what is required to reach agreement with members from distinct groups. Preregistered behavioral (N = 420) and neuroimaging experiments (N = 49) support model predictions: Seeking equitable agreements can lead to overly generous behavior toward partners from different groups alongside incorrect beliefs about prevailing norms of what is appropriate in groups and cultures other than one’s own

Neurocognitive Underpinnings of Aggressive Predation in Economic Contests

Michael Rojek-Giffin, Mael Lebreton, H. Steven Scholte, Frans van Winden, K. Richard Ridderinkhof, and Carsten K. W. De Dreu (2020). Journal of Cognitive Neuroscience

Learning rules of engagement for social exchange within and between groups

International audienceGlobalizing 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 individuals decipher distinct rules of engagement and adapt their behavior to reach agreements with partners from other cultural groups. Modeling individuals as Bayesian learners with inequality aversion reveals that individuals, in repeated ultimatum bargaining with responders sampled from different groups, can be more generous than needed. While this allows them to reach agreements, it also gives rise to biased beliefs about what is required to reach agreement with members from distinct groups. Preregistered behavioral ( N = 420) and neuroimaging experiments ( N = 49) support model predictions: Seeking equitable agreements can lead to overly generous behavior toward partners from different groups alongside incorrect beliefs about prevailing norms of what is appropriate in groups and cultures other than one’s own

On being unpredictable and winning

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 these questions in interactive attacker–defender contests, in which attackers invest to capture resources held and defended by their opponent. Study 1, a reanalysis of nine (un)published experiments (total N = 650), reveals significant cross-trial variability especially in proactive attacks and less in reactive defense. Study 2 (N = 200) shows that greater variability makes both attacker’s and defender’s next move more difficult to predict, especially when variability is due to occasional rather than (in)frequent extreme investments in conflict. Studies 3 (N = 27) and 4 (N = 106) show that precontest testosterone, a hormone associated with risk-taking and status competition, drives variability during attack which, in turn, increases sympathetic arousal in defenders and defender variability (Study 4). Rather than being motivated by wealth maximization, being unpredictable in conflict and competition emerges in function of the attacker’s desire to win “no matter what” and comes with significant welfare cost to both victor and victim