Scholars have observed people from a variety of cultures using a variety of gratitude-related practices to change their emotions, outlooks, and social relationships. Across 34 countries purposively sampled to cover a broad set of cross-cultural differences (total N = 10,696), we experimentally tested the effects of 6 brief gratitude interventions on subjective moods, life outlooks, and social evaluations. Compared to 3 control tasks, gratitude practices immediately produced theorized improvements in positive affect (d = 0.37), negative affect (d = -0.22), optimism (d = 0.24), life satisfaction (d = 0.12), indebtedness (d = 0.15), and envy (d = -0.16). Notably, these effects varied across different gratitude practices (0.00 < τpractice < 0.08) and countries (0.10 < τcountry < 0.19). For instance, based on existing evidence, stakeholders can expect gratitude interventions deployed in a randomly selected country to improve positive affect-but not our other measured outcomes. To guide future inquiry into why this might be the case, we provide exploratory Bayesian estimates of the importance of 12 cross-cultural differences.

Intuitive moral inference enables us to evaluate moral situations and judge their rightness or wrongness. Although Moral Foundations Theory provides a framework for understanding moral inference, its underlying neural basis remains unclear. To capture spontaneous neural activity during moral inference, participants were instructed to watch a film rich in moral content without making explicit judgments while undergoing fMRI scanning. Independent participants evaluated the moment-to-moment presence of twenty moral dimensions in the film. Correlation and consensus cluster analyses revealed four independent main moral dimensions: virtue, vice, hierarchy, and rebellion. While each dimension exhibited unique neural activation patterns, the temporoparietal junction and inferior parietal lobe were activated across all types of moral inference. These findings establish the low-dimensional nature for the neural basis of intuitive moral inference in everyday settings.

Abstract We conducted a transcultural adaptation and validation of the Perth Emotion Reactivity Scale for Brazilian contexts, introducing the Brazilian version (PERS-Br) in its standard and short forms. Participants were 452 Brazilian adults stratified by region. We investigated four structural models for the PERS-Br with confirmatory factor analyses. Reliability was assessed with internal consistency measures. Both versions of the PERS-Br demonstrated robust structural validity and reliability, with the hierarchical model emerging as the most adequate. Older participants exhibited higher Positive Reactivity scores, while younger participants leaned towards higher Negative Reactivity scores. The standard version of the PERS-Br presented potential redundancies. Further validations of the PERS-Br, exploring how it relates to other constructs and its correlations with psychophysiological measures, are recommended. Overall, the PERS-Br, especially the short-version, emerges as a promising tool for probing affective experiences in Brazil in future studies on emotional reactivity.

Climate change is currently one of humanity’s greatest threats. To help scholars understand the psychology of climate change, we conducted an online quasi-experimental survey on 59,508 participants from 63 countries (collected between July 2022 and July 2023). In a between-subjects design, we tested 11 interventions designed to promote climate change mitigation across four outcomes: climate change belief, support for climate policies, willingness to share information on social media, and performance on an effortful pro-environmental behavioural task. Participants also reported their demographic information (e.g., age, gender) and several other independent variables (e.g., political orientation, perceptions about the scientific consensus). In the no-intervention control group, we also measured important additional variables, such as environmentalist identity and trust in climate science. We report the collaboration procedure, study design, raw and cleaned data, all survey materials, relevant analysis scripts, and data visualisations. This dataset can be used to further the understanding of psychological, demographic, and national-level factors related to individual-level climate action and how these differ across countries.

### Key messages Vaccine misinformation on social media has strong effects on behaviour, and the evidence base for interventions to reduce these effects is limited, but better approaches to evidence generation are possible, say Kai Ruggeri and colleagues Effective population level vaccination campaigns are fundamental to public health.123 Counter campaigns, which are as old as the first vaccines,4 disrupt uptake and can threaten public health globally.4 In 2019, public health researchers linked increases in measles cases with the proliferation of global anti-vaccine campaigns.5 Some of these campaigns originated offline but were later amplified and expedited through social media, resulting in real world harms.6 Though crises and genuine safety concerns can also lower vaccine uptake,78 the return of measles after aggressive anti-vaccine campaigns prompted the World Health Organisation to list vaccine hesitancy among the greatest threats to global health (box 1).14 Box 1 ### Vaccine hesitancy Here, we use the term “vaccine hesitancy” as originally defined by WHO9: a “delay in acceptance or refusal of vaccination despite availability of vaccination services.” This definition, plus the expanded description of variation based on time, place, and population, gives a broad understanding but also allows us to distinguish vaccination behaviour from the underpinning psychological, environmental, and structural aspects influencing behaviour. This definition is most commonly used in literature pre-dating covid-19. Though there are debates about the most appropriate … RETURN TO TEXT

Effectively reducing climate change requires marked, global behavior change. However, it is unclear which strategies are most likely to motivate people to change their climate beliefs and behaviors. Here, we tested 11 expert-crowdsourced interventions on four climate mitigation outcomes: beliefs, policy support, information sharing intention, and an effortful tree-planting behavioral task. Across 59,440 participants from 63 countries, the interventions' effectiveness was small, largely limited to nonclimate skeptics, and differed across outcomes: Beliefs were strengthened mostly by decreasing psychological distance (by 2.3%), policy support by writing a letter to a future-generation member (2.6%), information sharing by negative emotion induction (12.1%), and no intervention increased the more effortful behavior-several interventions even reduced tree planting. Last, the effects of each intervention differed depending on people's initial climate beliefs. These findings suggest that the impact of behavioral climate interventions varies across audiences and target behaviors.

Understanding what factors are linked to public health behavior in a global pandemic is critical to mobilizing an effective public health response. Although public policy and health messages are often framed through the lens of individual benefit, many of the behavioral strategies needed to combat a pandemic require individual sacrifices to benefit the collective welfare. Therefore, we examined the relationship between individuals' morality and their support for public health measures. In a large-scale study with samples from 68 countries worldwide (Study 1; N = 46,576), we found robust evidence that moral identity, morality-as-cooperation, and moral circles are each positively related to people's willingness to engage in public health behaviors and policy support. Together, these moral dispositions accounted for 9.8%, 10.2%, and 6.2% of support for limiting contact, improving hygiene, and supporting policy change, respectively. These morality variables (Study 2) and Schwartz's values dimensions (Study 3) were also associated with behavioral responses across 42 countries in the form of reduced physical mobility during the pandemic. These results suggest that morality may help mobilize citizens to support public health policy.

Stimulating CT-afferents by forearm caresses produces the subjective experience of pleasantness in the receiver and modulates subjective evaluations of viewed affective images. Receiving touch from another person includes the social element of another person's presence, which has been found to influence affective image evaluations without involving touch. The current study investigated whether these modulations translate to facial muscle responses associated with positive and negative affect across touch-involving and mere presence conditions. Female participants (N = 40, M(age) = 22.4, SD = 5.3) watched affective images (neutral, positive, negative) while facial electromyography was recorded (sites: zygomaticus, corrugator). Results from ANOVAs showed that providing touch to another person or oneself modulated zygomaticus site responses when viewing positive images. Providing CT-afferent stimulating touch (i.e., forearm caresses) to another person or oneself dampened the positive affective facial muscle response to positive affective images. Providing touch to another person generally increased corrugator facial muscle activity related to negative affect. Receiving touch did not modulate affective facial muscle responses during the viewing of affective images but may have effects on later cognitive processes. Together, previously reported social and touch modulations of subjective evaluations of affective images do not translate to facial muscle responses during affective image viewing, which were differentially modulated.

This cross-cultural study compared judgments of moral wrongness for physical and emotional harm with varying combinations of in-group vs. out-group agents and victims across six countries: the United States of America (N = 937), the United Kingdom (N = 995), Romania (N = 782), Brazil (N = 856), South Korea (N = 1776), and China (N = 1008). Consistent with our hypothesis we found evidence of an insider agent effect, where moral violations committed by outsider agents are generally considered more morally wrong than the same violations done by insider agents. We also found support for an insider victim effect where moral violations that were committed against an insider victim generally were seen as more morally wrong than when the same violations were committed against an outsider, and this effect held across all countries. These findings provide evidence that the insider versus outsider status of agents and victims does affect moral judgments. However, the interactions of these identities with collectivism, psychological closeness, and type of harm (emotional or physical) are more complex than what is suggested by previous literature.

This study investigates the neural correlates of identity and reputation processing in cooperative decision-making during the Public Goods Game (PGG). Using functional near-infrared spectroscopy (fNIRS), we examined how different types of social information—co-player facial photos, reputational scores, and a combination of both—influence activity in the dorsolateral prefrontal cortex (dlPFC) and ventromedial prefrontal cortex (vmPFC). Our findings suggest that the dlPFC is crucial for integrating reputational information, reflecting its role in cognitive control and modulation of expectations during cooperative interactions. The vmPFC, on the other hand, is involved in attributing value to the cooperative decision by synthesizing identity and reputation cues. Reputation alone elicited greater dlPFC activity, highlighting the cognitive demands of evaluating past behaviors. When both identity and reputation information were presented, vmPFC activity increased, indicating greater value processing. These results demonstrate the distinct but complementary roles of the dlPFC and vmPFC in processing social cues during cooperative decision-making. ### Competing Interest Statement The authors have declared no competing interest.

Procedural learning is the acquisition of motor and non-motor skills through a gradual process that increases with practice. Impairments in procedural learning have been consistently demonstrated in neurodevelopmental, neurodegenerative, and neuropsychiatric disorders. Considering that noninvasive brain stimulation modulates brain activity and boosts neuroplastic mechanisms, we reviewed the effects of coupling transcranial direct current stimulation (tDCS) with training methods for motor and non-motor procedural learning to explore tDCS potential use as a tool for enhancing implicit learning in healthy and clinical populations. The review covers tDCS effects over i. motor procedural learning, from basic to complex activities; ii. non-motor procedural learning; iii. procedural rehabilitation in several clinical populations. We conclude that targeting the primary motor cortex and prefrontal areas seems the most promising for motor and non-motor procedural learning, respectively. For procedural rehabilitation, the use of tDCS is yet at an early stage but some effectiveness has been reported for implicit motor and memory learning. Still, systematic comparisons of stimulation parameters and target areas are recommended for maximising the effectiveness of tDCS and its robustness for procedural rehabilitation.

The COVID-19 pandemic has affected all domains of human life, including the economic and social fabric of societies. One of the central strategies for managing public health throughout the pandemic has been through persuasive messaging and collective behaviour change. To help scholars better understand the social and moral psychology behind public health behaviour, we present a dataset comprising of 51,404 individuals from 69 countries. This dataset was collected for the International Collaboration on Social & Moral Psychology of COVID-19 project (ICSMP COVID-19). This social science survey invited participants around the world to complete a series of moral and psychological measures and public health attitudes about COVID-19 during an early phase of the COVID-19 pandemic (between April and June 2020). The survey included seven broad categories of questions: COVID-19 beliefs and compliance behaviours; identity and social attitudes; ideology; health and well-being; moral beliefs and motivation; personality traits; and demographic variables. We report both raw and cleaned data, along with all survey materials, data visualisations, and psychometric evaluations of key variables.

Research on racial bias in social and cognitive psychology has focused on automatic cognitive processes such as categorisation or stereotyping. Neuroimaging has revealed differences in the neural circuit when processing social information about one’s own or another’s ethnicity. This review investigates the influence of racial bias on human behaviour by reviewing studies that examined changes in neural circuitry (i.e. ERP responses) during automatic and controlled processes elicited by specific tasks. This systematic analysis of specific ERP components across different studies provides a greater understanding of how social contexts are perceived and become associated with specific stereotypes and behavioural predictions. Therefore, investigating these related cognitive and neurobiological functions can further our understanding of how racial bias affects our cognition more generally and guide more effective programs and policies aimed at its mitigation.

Scientific evidence regularly guides policy decisions 1 , with behavioural science increasingly part of this process 2 . In April 2020, an influential paper 3 proposed 19 policy recommendations (‘claims’) detailing how evidence from behavioural science could contribute to efforts to reduce impacts and end the COVID-19 pandemic. Here we assess 747 pandemic-related research articles that empirically investigated those claims. We report the scale of evidence and whether evidence supports them to indicate applicability for policymaking. Two independent teams, involving 72 reviewers, found evidence for 18 of 19 claims, with both teams finding evidence supporting 16 (89%) of those 18 claims. The strongest evidence supported claims that anticipated culture, polarization and misinformation would be associated with policy effectiveness. Claims suggesting trusted leaders and positive social norms increased adherence to behavioural interventions also had strong empirical support, as did appealing to social consensus or bipartisan agreement. Targeted language in messaging yielded mixed effects and there were no effects for highlighting individual benefits or protecting others. No available evidence existed to assess any distinct differences in effects between using the terms ‘physical distancing’ and ‘social distancing’. Analysis of 463 papers containing data showed generally large samples; 418 involved human participants with a mean of 16,848 (median of 1,699). That statistical power underscored improved suitability of behavioural science research for informing policy decisions. Furthermore, by implementing a standardized approach to evidence selection and synthesis, we amplify broader implications for advancing scientific evidence in policy formulation and prioritization.

Resumo O crescimento das redes sociais deu força sem precedentes aos discursos de ódio, que têm causado danos globalmente. Este artigo objetivou discutir os substratos sociocognitivos do discurso de ódio e o papel das redes sociais no agravamento do problema, integrando conhecimentos das neurociências, da Psicologia Social, Análise Crítica do Discurso, entre outras, propondo uma breve revisão narrativa para auxiliar a compreensão e o combate ao discurso de ódio no contexto brasileiro. Por meio da articulação dessas áreas, foram abordados temas centrais ao discurso de ódio: sua natureza como prática social e os processos sociocognitivos subjacentes a ele, como a categorização social e formação de estereótipos, preconceitos e identidade social, fenômenos que podem mediar conflitos interpessoais e intergrupais. A partir de conceitos já bastante consolidados, buscou-se literatura atualizada para compreender e ilustrar a dimensão da problemática dos discursos de ódio. Este trabalho aponta direções estratégicas para combater e mitigar efeitos negativos dos discursos de ódio, para promover sociedades mais justas e cooperativas, com adoção de medidas socioeducativas dentro e fora da Internet.

Players' identity and their reputation are known to influence cooperation in economic games, but little is known about how they interact. Our study aimed to understand how presenting pre-programmed co-players' identities (face photos; names) along with their previous cooperation history (reputation) could influence participants' cooperative decisions in a public goods game. Participants (N = 759) were allocated to one of six experimental groups: (i) control (no information); (ii) only reputation (neutral, free-rider, or cooperative); (iii) only face; (iv) face with reputation; (v) only name; (vi) name with reputation. In the reputation group, cooperation significantly decreased when free-riders were playing and significantly increased when they were cooperators. Person's identity affected cooperativeness only when combined with reputation: face photo mitigated the negative effect of the free-rider reputation, while name identity mitigated any significant effect expected for reputation. Our study suggests a hierarchy: reputation changes cooperation, but a person's identity can modulate reputation.

We present a largescale, pre-registered examination of factors that explain why citizens of certain nations might show higher levels of national narcissism than others. National narcissism is the belief that one’s nation is exceptional yet undervalued. It is related to several social ills, including conspiracy beliefs, intergroup aggression, extremism, and rejection of science. We theorized that national narcissism would be related to the nature of relations between countries. We expected it to be associated with higher levels of external conflict and lower levels of globalization. Using multilevel modeling across 56 countries (n=50,757), we found that citizens of less globalized nations showed higher average national narcissism. However, external conflict was unrelated to national narcissism. We also tested whether citizens’ national narcissism was higher in countries led by populists but found no evidence for this effect. At the individual-level, higher individual narcissism, self-esteem, and right-wing political orientation positively predicted higher national narcissism.

Morality has traditionally been described in terms of an impartial and objective "moral law", and moral psychological research has largely followed in this vein, focusing on abstract moral judgments. But might our moral judgments be shaped not just by what the action is, but who is doing it? We looked at ratings of moral wrongness, manipulating whether the person doing the action was a friend, a refugee, or a stranger. We looked at these ratings across various moral foundations, and conducted the study in Brazil, US, and UK samples. Our most robust and consistent findings are that purity violations were judged more harshly when committed by ingroup members and less harshly when committed by the refugees in comparison to the unspecified agents, the difference between refugee and unspecified agents decays from liberals to conservatives, i.e., conservatives judge them more harshly than liberals do, and Brazilians participants are harsher than the US and UK participants. Our results suggest that purity violations are judged differently according to who committed them and according to the political ideology of the judges. We discuss the findings in light of various theories of groups dynamics, such as moral hypocrisy, moral disengagement, and the black sheep effect.

The growth of social networks has given unprecedented strength to hate speech, which has caused damage globally. This article aimed to discuss the sociocognitive substrates of hate speech and the role of social networks in exacerbating the problem, integrating knowledge from neurosciences, Social Psychology, Critical Discourse Analysis, among others, proposing a brief narrative review to aid understanding and combat hate speech in the Brazilian context. Through the articulation of these areas, central themes were addressed to hate speech: its nature as a social practice and the sociocognitive processes underlying it, such as social categorization and the formation of stereotypes, prejudices, and social identity, phenomena that can mediate interpersonal and intergroup conflicts. From already well-established concepts, up-to-date literature was sought to understand and illustrate the dimension of the problem of hate speech. This work points out strategic directions to combat and mitigate the negative effects of hate speech, to promote more just and cooperative societies, with the adoption of socio-educational measures both on and off the Internet.