The neuroscience of intergroup threat and violence

Authoritarianism and the brain: Structural MR correlates associated with polarized left- and right-wing ideology traits

Authoritarian attitudes across the political spectrum foster radical behaviors, which adversely affect the social fabric. Both left-wing (LWA) and right-wing (RWA) forms of authoritarianism have been described in relation to their psychological correlates, yet little is known about their neurobiological basis. In this study, we explored brain structural correlates (e.g., in cortical thickness (CT) and gray matter (GM) volume) of authoritarianism. For this purpose, we assessed authoritarian dispositions in a sample of 100 young adults and collected 3 T MR images. Images were computed using the CAT12 toolbox. Behaviorally, both the LWA and RWA were positively associated with negative urgency; the LWA also showed a robust positive association with trait anxiety. At the neural level, results showed a negative correlation (r = -0.48) between RWA and a GM volume cluster located in the dorsomedial prefrontal cortex (dmPFC). In addition, we also observed a negative correlation (r = -0.41) between the LWA anti-hierarchical aggression subscale and a CT cluster located in the right anterior insula. Additionally, the resulting clusters converged with further left-wing and right-wing ideology scales related to LWA and RWA, thus providing a robustness check. These results are supported by previous studies showing the relevance of the dmPFC and the anterior insula on social cognition and empathy/inhibitory control, respectively.

Moral-dilemma judgments by individuals and groups: Are many heads really more utilitarian than one?

Moral dilemmas often involve a conflict between action-options that maximize outcomes for the greater good (utilitarianism) and inaction-options that conform to moral norms (deontology). Previous research suggests that, compared to individuals, groups show stronger support for outcome-maximizing actions that violate moral norms. The current study used a computational modeling approach to investigate whether this difference is driven by (1) stronger sensitivity to consequences, (2) weaker sensitivity to moral norms, or (3) weaker action aversion in moral-dilemma judgments made by groups. The results suggest that groups show a stronger sensitivity to consequences than individuals. Groups and individuals did not differ in terms of their sensitivity to moral norms and their general action aversion. The findings challenge the idea that groups are less action averse and less concerned about violating moral norms than individuals and instead suggest that group decisions are more strongly guided by outcomes for the greater good.

Neural synchronization and its impact on intergroup attitudes in dynamic interactions

Dynamic transitions between competition and cooperation are common in real-world intergroup interactions, yet prior research has typically examined competition or cooperation in isolation. This study explored how transitions between competition and cooperation influenced intergroup attitudes and the neural processes involved. Using functional Near-Infrared Spectroscopy (fNIRS) hyperscanning, we recorded brain activity from 69 dyads during interactions. Results showed that cooperation enhanced neural synchronization in the right temporoparietal junction (rTPJ), leading to more positive outgroup attitudes. In contrast, competition increased synchronization in the right dorsolateral prefrontal cortex (rDLPFC), correlating with decreased outgroup likability. The sequence of interactions was critical, with the first interaction exerting a carryover effect on the next. Cooperation buffered the negative effects of later competition, while competition weakened the positive effects of subsequent cooperation. These findings emphasized the importance of understanding dynamic intergroup interactions and highlighted the potential of cooperation to mitigate biases and improve intergroup relations.

Understanding intergroup violence justification: the role of ethnicity and perceived threat in Israeli society

Research has shown that perceived realistic and symbolic threats are linked with negative attitudes and prejudice toward out-group members. Additionally, levels of perceived group threat regarding out-groups can affect intergroup violence justification. Based on the Integrated Threat Theory (ITT), the current study aimed to expand existing knowledge by examining a conceptual model in which perceived threat mediates the relationship between ethnicity and intergroup violence justification among Jews and Arabs in Israel. The study involved 324 Israeli-Jewish and 325 Israeli-Arabs, who answered questions regarding perceived out-group threat and intergroup violence justification. Findings revealed that (a) Jews were more likely to justify intergroup violence than Arabs, and (b) perceived realistic threat mediates the relationship between ethnic affiliation and intergroup violence justification only among Jews. These results underscore the importance of understanding intergroup conflicts in the field of criminology.

Resource scarcity aggravates ingroup bias: Neural mechanisms and cross-scenario validation

Previous studies examining the relationship between ingroup bias and resource scarcity have produced heterogeneous findings, possibly due to their focus on the allocation of positive resources (e.g. money). This study aims to investigate whether ingroup bias would be amplified or eliminated when perceived survival resources for counteracting negative stimuli are scarce. For this purpose, we exposed the participants and another confederate of the experimenters (ingroup/outgroup member) to a potential threat of unpleasant noise. Participants received some 'relieving resources' to counteract noise administration, the amount of which may or may not be enough for them and the confederate in different conditions (i.e. abundance vs. scarcity). First, a behavioural experiment demonstrated that intergroup discrimination manifested only in the scarcity condition; in contrast, the participants allocated similar amounts of resource to ingroup and outgroup members in the abundance condition, indicating a context-dependent allocation strategy. This behavioural pattern was replicated in a follow-up neuroimaging experiment, which further revealed that when contrasting scarcity with abundance, there was higher activation in the anterior cingulate cortex (ACC) as well as stronger functional connectivity of the ACC with the empathy network (including the temporoparietal junction and medial prefrontal cortex) for ingroup compared to outgroup members. We suggest that ACC activation reflects the mentalizing process toward ingroup over outgroup members in the scarcity condition. Finally, the ACC activation level significantly predicted the influence of resource scarcity on ingroup bias in hypothetical real-life situations according to a follow-up examination.

Representation of intergroup conflict in the human brain

This NeuroView explores intergroup conflict by synthesizing intergroup differences with three group-related neurocognitive processes. We suggest that intergroup differences at the aggregated-group level and interpersonal level are neurally dissociated and independently influence group dynamics as well as ingroup-outgroup conflicts.

Exposure to hate speech deteriorates neurocognitive mechanisms of the ability to understand others' pain

The widespread ubiquity of hate speech affects people's attitudes and behavior. Exposure to hate speech can lead to prejudice, dehumanization, and lack of empathy towards members of outgroups. However, the impact of exposure to hate speech on empathy and propensity to attribute mental states to others has never been directly tested empirically. In this fMRI study, we examine the effects of exposure to hate speech on neural mechanisms of empathy towards ingroup (Poles) versus outgroup members (Arabs). Thirty healthy young adults were randomly assigned to 2 groups: hateful and neutral. During the fMRI study, they were initially exposed to hateful or neutral comments and subsequently to narratives depicting Poles and Arabs in pain. Using whole-brain and region of interest analysis, we showed that exposure to derogatory language about migrants attenuates the brain response to someone else's pain in the right temporal parietal junction (rTPJ), irrespective of group membership (Poles or Arabs). Given that rTPJ is associated with processes relevant to perspective-taking, its reduced activity might be related to a decreased propensity to take the psychological perspective of others. This finding suggests that hate speech affects human functioning beyond intergroup relations.

Addressing racial misinformation at school: a psycho-social intervention aimed at reducing ethnic moral disengagement in adolescents

The present study aims to examine whether by promoting the socio-analytic thinking it is possible to intervene in the reliance on ethnic moral disengagement as a negative consequence of racial misleading news, that can seriously contribute to the diffusion of ethnic prejudice. We focus on the neglected phenomenon of racial hoaxes, which can be defined as misleading news stories dealing with health or safety threats, in which the protagonist is described in terms of ethnicity or nationality. The intervention procedure has been created starting from the well-established literature focused on media biases’ reflection, integrated with the recent studies on ‘mediated intergroup contact’ where the observation of the person belonging to the outgroup is crucial for prejudice reduction. The intervention involved 83 adolescents (Mage = 13.9; SDage = 0.9) and it was composed of two different parts, one focused on the analytical racial hoax reading, and the other focused on racial hoax rewriting after the ‘mediated contact’, represented by an alternative story given by the African protagonist. The results show that in dealing with misleading news, the promotion of this social-analytic processing reduces ethnic biases of moral disengagement. In particular, it was found that analytical processes are supported by the participants’ level of propensity for analytical reasoning and that these processes directly hinder distorted ethnic beliefs. Overall, these results suggest that improving social-analytic processes related to reflexivity could be an effective intervention to counter those distorted beliefs, such as ethnic disengagement beliefs, associated with discrimination and racial prejudice.

The Dual Effect of COVID-19 on Intergroup Conflict in the Korean Peninsula

The coronavirus pandemic has fundamentally shifted the way human beings interact, both as individuals and groups, in the face of such a widespread outbreak. This paper seeks to investigate the effects of COVID-19 on intergroup emotions and attitudes within an intractable intergroup conflict, specifically, through the lens of the Korean conflict. Using a two-wave, cross-sectional design, this study was able to track the profound psychological changes in intergroup emotions and attitudes both prior to the pandemic and during its onslaught. Results of these two wave representative samples show that South Korean citizens demonstrated higher levels of fear of their neighbors in North Korea after the outbreak of COVID-19 than before. In turn, this led to increased societal support of hostile government policies towards North Koreans. Conversely, the same participants exhibited higher levels of empathy towards North Koreans during the pandemic, which led to a higher willingness to collaborate with their outgroup. This dual effect on intergroup emotions within intractable conflicts brings forth new avenues from which societies may be able to restrain the destructive influence of the COVID-19 threat on intergroup relations - as well as harvesting its constructive potential for reconciling warring intergroup relations.

Neural Mechanisms of Intergroup Exclusion and Retaliatory Aggression

Aggression occurs frequently and severely between rival groups. Although there has been much study into the psychological and socio-ecological determinants of intergroup aggression, the neuroscience of this phenomenon remains incomplete. To examine the neural correlates of aggression directed at outgroup (versus ingroup) targets, we recruited 35 healthy young male participants who were current or former students of the same university. While undergoing functional MRI, participants completed an aggression task against both an ingroup and an outgroup opponent in which their opponents repeatedly provoked them at varying levels and then participants could retaliate. Participants were then socially included and then excluded by two outgroup members and then completed the same aggression task against the same two opponents. Both before and after outgroup exclusion, aggression towards outgroup members was positively associated with activity in the ventral striatum during decisions about how aggressive to be towards their outgroup opponent. Aggression towards outgroup members was also linked to greater post-exclusion activity in the rostral and dorsal medial prefrontal cortex during provocation from their outgroup opponent. These altered patterns of brain activity suggest that frontostriatal mechanisms may play a significant role in motivating aggression towards outgroup members.