Altruism toward in-group members as a reputation mechanism

Beyond empathy: Cognitive capabilities increase or curb altruism in middle childhood

Altruistic behavior, which intentionally benefits a recipient without expectation of a reward or at a cost to the actor, is observed throughout the lifespan from everyday interactions to emergency situations. Empathy has long been considered a major driver of altruistic action, but the social information processing model supports the idea that other cognitive processes may also play a role in altruistic intention and behavior. Our aim was to investigate how visual analysis, attention, inhibitory control, and theory of mind capabilities uniquely contribute to predicting altruistic intention and behavior in a sample of 67 French children (35 girls and 32 boys; Mage = 9.92 ± 0.99 years) from Paris and neighboring suburbs. Using a Bayesian analysis framework, we showed that in younger grade levels visual analysis and selective attention are strong predictors of altruistic intention and that inhibitory control strongly predicts altruistic behavior in a dictator game. Processes underlying theory of mind, however, negatively predict altruistic behavior in the youngest grade. In higher grade levels, we found that stronger attention and inhibitory control predicts lower altruistic intention and behavior. Empathy was not found to predict altruistic intention or behavior. These results suggest that different cognitive capabilities are involved in altruistic intention and behavior and that their contribution changes throughout middle childhood as social constraints deepen and altruism calls on more complex reasoning.

Group Formation and the Evolution of Human Social Organization

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 understand why groups form ex nihilo, how groups evolve into complex multilayered social structures, and what explains fission-fusion dynamics. Here we address group formation and the evolution of social organization at both the proximate and ultimate level of analysis. Building on models of fitness interdependence and cooperation, we propose that socioecologies can create positive interdependencies among strangers and pave the way for the formation of stable coalitions and groups through reciprocity and reputation-based partner selection. Such groups are marked by in-group bounded, parochial cooperation together with an array of social institutions for managing the commons, allowing groups to scale in size and complexity while avoiding the breakdown of cooperation. Our analysis reveals how distinct group cultures can endogenously emerge from reciprocal cooperation, shows that social identification and group commitment are likely consequences rather than causes of group cooperation, and explains when intergroup relations gravitate toward peaceful coexistence, integration, or conflict.

Watching eyes effect: the impact of imagined eyes on prosocial behavior and satisfactions in the dictator game

The concept of the watching eyes effect suggests that the presence of eye or eye-like cues can influence individual altruistic behavior. However, few studies have investigated the effects of imagined eyes on altruistic behaviors and the psychological measures of dictators and recipients in the dictator game. This study used a 2 (Presentation Mode: Imagined/Visual) 2 (Cue Type: Eye/Flower) between-subject design and measured the effects of recipients' psychological variables and the communication texts between the dictator and the recipient. The results showed that there was a significant interaction between Presentation Mode and Cue Type. In the imagined condition, the dictator exhibited more altruistic behavior than in the visual condition. However, there was no significant difference in altruistic behavior between the Imagined Eye and Imagined Flower conditions. In addition, the study found that the Cue Type had a significant main effect on the recipients' satisfaction with the allocation outcome. Notably, in the Visual Flower condition, the dictator used more egoistic norm words when communicating with the recipient than other conditions. This study provides novel evidence on the effect of imagined social cues on individual behavior in the dictator game, and to some extent validates the robustness of the watching eyes effect under manipulation of higher-level verbal cognitive processes. At the same time, the study is the first to explore the impacts on recipients' psychological variables and the communication texts. These efforts offer new insights into the psychological and cognitive mechanisms underlying the watching eyes effect.

Compartir por altruismo o equidad: Prosocialidad según el nivel socioeconómico

La paradoja “Tener menos dar más” consiste en la generosidad de personas con bajos recursos económicos. Sin embargo, sólo se había explorado con estudiantes de clase media alta y con juegos del dictador con puntos. En este estudio realizamos el juego del dictador con dinero con 24 personas, de ocupaciones diversas y de niveles socioeconómicos (NSE) altos y bajos, con el objetivo de observar si la paradoja se mantenía y conocer los motivos que los participantes daban a su conducta. Los resultados muestran que las personas de NSE alto dieron significativamente más en promedio (M = 18.2, DE = 4.06); sin embargo, las personas de NSE bajo en general tendieron a dar la mitad de su dinero (M = 10, DE = 4.08) apelando a razones de equidad. Si bien la paradoja “Tener menos dar más” no se observó, se discuten los procesos que llevan a las personas de diferentes recursos económicos a compartir.

Effects of morality and reputation on sharing behaviors in human-robot teams

Introduction

The relationship between robots and humans is becoming increasingly close and will become an inseparable part of work and life with humans and robots working together. Sharing, which involves distributing goods between individuals and others, involves individuals as potential beneficiaries and the possibility of giving up the interests of others. In human teams, individual sharing behaviors are influenced by morality and reputation. However, the impact on individuals' sharing behaviors in human-robot collaborative teams remains unclear-individuals may consider morality and reputation differently when sharing with robot or human partners. In this study, three experiments were conducted using the dictator game paradigm, aiming to compare the effects and mechanisms of morality and reputation on sharing behaviors in human and human-robot teams.

Methods

Experiment 1 involving 18 participants was conducted. Experiment 2 involving 74 participants was conducted. Experiment 3 involving 128 participants was conducted.

Results

Experiment 1 validated the differences in human sharing behaviors when the agents were robots and humans. Experiment 2 verifies that moral constraints and reputation constraints affect sharing behaviors in human-robot teams. Experiment 3 further reveals the mechanism of differences in sharing behaviors in human-robot teams, where reputation concern plays a mediating role in the impact of moral constraint on sharing behaviors, and the agent type plays a moderating role in the impact of moral constraint on reputation concern and sharing behaviors.

Discussion

The results of this study contribute to a better understanding of the interaction mechanism of human-robot teams. In the future, the formulation of human-robot collaborative team rules and the setting of interaction environments can consider the potential motivation of human behavior from both morality and reputation perspectives and achieve better work performance.

Behavioral evidence for global consciousness transcending national parochialism

While national parochialism is commonplace, individual differences explain more variance in it than cross-national differences. Global consciousness (GC), a multi-dimensional concept that includes identification with all humanity, cosmopolitan orientation, and global orientation, transcends national parochialism. Across six societies (N = 11,163), most notably the USA and China, individuals high in GC were more generous allocating funds to the other in a dictator game, cooperated more in a one-shot prisoner's dilemma, and differentiated less between the ingroup and outgroup on these actions. They gave more to the world and kept less for the self in a multi-level public goods dilemma. GC profiles showed 80% test-retest stability over 8 months. Implications of GC for cultural evolution in the face of trans-border problems are discussed.

Reputations for treatment of outgroup members can prevent the emergence of political segregation in cooperative networks

Reputation systems promote cooperation and tie formation in social networks. But how reputations affect cooperation and the evolution of networks is less clear when societies are characterized by fundamental, identity-based, social divisions like those centered on politics in the contemporary U.S. Using a large web-based experiment with participants (N = 1073) embedded in networks where each tie represents the opportunity to play a dyadic iterated prisoners' dilemma, we investigate how cooperation and network segregation varies with whether and how reputation systems track behavior toward members of the opposing political party (outgroup members). As predicted, when participants know others' political affiliation, early cooperation patterns show ingroup favoritism. As a result, networks become segregated based on politics. However, such ingroup favoritism and network-level political segregation is reduced in conditions in which participants know how others behave towards participants from both their own party and participants from the other party. These findings have implications for our understanding of reputation systems in polarized contexts.

Reputation Reminders: When do Eye Cues Promote Prosocial Behavior?

The watching eyes effect has gained significant attention in recent years both from scientists and from policy makers and professionals in the field. The phenomenon posits that the mere presence of eye cues can promote prosocial behavior. However, there is a growing debate about the generality of the effect across various measures and contexts. This review seeks to combine various distinct -and formerly isolated- perspectives by identifying four key components for effective interventions based on the watching eyes effect: Anonymity, crowdedness, costs, and exposure. Eye cues need to reduce perceived anonymity, be placed in non-crowded places, target low-cost prosocial acts and appear for a short amount of time. Next to these conditions, we discuss implications for other cues to reputation and recommend directions that will stimulate further research and applications in society.

Ancestral social environments plus nonlinear benefits can explain cooperation in human societies

Human cooperation (paying a cost to benefit others) is puzzling from a Darwinian perspective, particularly in groups with strangers who cannot repay nor are family members. The beneficial effects of cooperation typically increase nonlinearly with the number of cooperators, e.g., increasing returns when cooperation is low and diminishing returns when cooperation is high. Such nonlinearity can allow cooperation between strangers to persist evolutionarily if a large enough proportion of the population are already cooperators. However, if a lone cooperator faces a conflict between the group's and its own interests (a social dilemma), that raises the question of how cooperation arose in the first place. We use a mathematically tractable evolutionary model to formalise a chronological narrative that has previously only been investigated verbally: given that ancient humans interacted mostly with family members (genetic homophily), cooperation evolved first by kin selection, and then persisted in situations with nonlinear benefits as homophily declined or even if interactions with strangers became the norm. The model also predicts the coexistence of cooperators and defectors observed in the human population (polymorphism), and may explain why cooperators in behavioural experiments prefer to condition their contribution on the contributions of others (conditional cooperation in public goods games).

Being Negatively Cued, are People Less Cooperative? The Influence of Watching Eyes on Cooperative Behavior

In the course of human evolution, watching eyes have had an important influence on individual cooperative behavior. However, researchers have not explored how the valence of watching eyes affects cooperative behavior. Therefore, this study includes three studies to investigate the effect of watching eyes with different valences on cooperative behavior. The results showed that positive watching eyes (vs. negative watching eyes) induced positive emotions (PA) in the participants and thus increased their tendency to cooperate (Studies 1-2). The role of the decision maker (making decisions for oneself vs. making decisions on behalf of others) moderates the effect of watching eyes on cooperative behavior through emotion (Study 3). In conclusion, the valence of watching eyes significantly affects cooperation. This study not only further enriches research on environmental stimulation and cooperation but also provides inspiration and a reference for solving problems of cooperation in social dilemmas.

Networks of reliable reputations and cooperation: a review

Reputation has been shown to provide an informal solution to the problem of cooperation in human societies. After reviewing models that connect reputations and cooperation, we address how reputation results from information exchange embedded in a social network that changes endogenously itself. Theoretical studies highlight that network topologies have different effects on the extent of cooperation, since they can foster or hinder the flow of reputational information. Subsequently, we review models and empirical studies that intend to grasp the coevolution of reputations, cooperation and social networks. We identify open questions in the literature concerning how networks affect the accuracy of reputations, the honesty of shared information and the spread of reputational information. Certain network topologies may facilitate biased beliefs and intergroup competition or in-group identity formation that could lead to high cooperation within but conflicts between different subgroups of a network. Our review covers theoretical, experimental and field studies across various disciplines that target these questions and could explain how the dynamics of interactions and reputations help or prevent the establishment and sustainability of cooperation in small- and large-scale societies.

This article is part of the theme issue ‘The language of cooperation: reputation and honest signalling’.

The Emergence of Lying for Reputational Concerns in 5-Year-Olds

Research suggests that even young children engage in strategic behaviors to manipulate the impressions others form of them and that they manage their reputation in order to cooperate with others. The current study investigated whether young children also lie in order to manage their, or their group’s, reputation in front of ingroup and outgroup members. Five-year old children (n=55) were randomly assigned to an individual reputation condition or a group reputation condition. Then, they played a mini dictator game in which they could share privately any number of their or their group’s stickers with an anonymous child. Participants then met ingroup and outgroup members, established through a minimal group design, via a pre-recorded, staged Skype call. Group members asked the participant how many stickers she, or her group, had donated. Results revealed that children stated to peers to have donated more than their actual donation, with no differences between conditions and no difference toward ingroup and outgroup members. Findings suggest that by 5years of age, children use lying as a strategy to manage their reputation.

No effect of 'watching eyes': An attempted replication and extension investigating individual differences

Some evidence suggests that people behave more cooperatively and generously when observed or in the presence of images of eyes (termed the 'watching eyes' effect). Eye images are thought to trigger feelings of observation, which in turn motivate people to behave more cooperatively to earn a good reputation. However, several recent studies have failed to find evidence of the eyes effect. One possibility is that inconsistent evidence in support of the eyes effect is a product of individual differences in sensitivity or susceptibility to the cue. In fact, some evidence suggests that people who are generally more prosocial are less susceptible to situation-specific reputation-based cues of observation. In this paper, we sought to (1) replicate the eyes effect, (2) replicate the past finding that people who are dispositionally less prosocial are more responsive to observation than people who are more dispositionally more prosocial, and (3) determine if this effect extends to the watching eyes effect. Results from a pre-registered study showed that people did not give more money in a dictator game when decisions were made public or in the presence of eye images, even though participants felt more observed when decisions were public. That is, we failed to replicate the eyes effect and observation effect. An initial, but underpowered, interaction model suggests that egoists give less than prosocials in private, but not public, conditions. This suggests a direction for future research investigating if and how individual differences in prosociality influence observation effects.

"Watching Eyes" Triggers Third-Party Punishment: The Role of Emotion Within the Eyes

Third-party punishment refers to a behavioral phenomenon whereby people punish wrongdoers even if their sanction incurs personal costs but yields no direct benefits. Given the eye cues demonstrated ability to convey signals of being observed, its effect on third-party punishment, driven by virtue of its effects on others' perceptions, was investigated. In addition, emotional message featured in the eye region is crucial in social interaction, whether the emotion within the eyes serves this effect with varying degrees of influence has rarely considered. The present study aimed at exploring (a) the watching eyes effect on the third-party punishment and (b) whether this effect varies from negative eyes to positive eyes. By two experiments using a modified Third-Party Dictator Game, we displayed either eye images or control images above the question on whether to punish the dictators or not. There was no emotional diversity of eye cues in Experiment 1, and most participants tended to punish for unfair offer. However, the appearance of eye images increased the punishment relative to control images. In Experiment 2, the eye cues were subdivided into positive and negative. The effect of watching eyes on the third-party punishment was significantly stronger when the eyes were negative than positive. Results revealed that eye cues play a role in promoting the third-party punishment and offer a potential insight into the mixed findings, such that the emotion within the eyes, especially the negative expression in the eyes, may influence the watching eyes effect.

Pathogen Threat and In-group Cooperation

Disease-causing parasites and pathogens play a pivotal role in intergroup behavior. Previous studies have suggested that the selection pressure posed by pathogen threat has resulted in in-group assortative sociality, including xenophobia and in-group favoritism. While the current literature has collated numerous studies on the former, strikingly, there has not been much research on the relationship between pathogen threat and in-group cooperation. Drawing upon prior studies on the function of the behavioral immune system (BIS), we argued that the BIS might facilitate cooperation with in-group members as a reactive behavioral immune response to pathogen threat. More specifically, we held that individuals might utilize cooperative behavior to ensure that they can receive social support when they have contracted an infectious disease. We reviewed existing findings pertaining to the potential role of the BIS in in-group cooperation and discussed directions for future studies.

Vigilant Self–Regulation, Cues of being Watched and Cooperativeness

The present research examined the interplay of individual differences in self–regulatory mechanisms as outlined in regulatory focus theory (promotion– and prevention–focus) and a cue of being watched in the context of cooperative behaviour. Study 1 revealed that the more individuals’ habitual self–regulatory orientation is dominated by a vigilant prevention focus, the more likely they are to act cooperatively (i.e. to donate money to natural conservation organizations) when a subtle cue of being watched renders reputational concerns salient. In contrast, when no such cue is provided individuals’ habitual vigilant self–regulatory orientation is negatively related to cooperative behaviour. Study 2 replicated the results of the initial study and examined interpersonal sensitivity (empathic concern) as a potential mediator of the observed effects. Copyright © 2010 John Wiley & Sons, Ltd.

Using Images of Eyes to Enhance Green Brand Purchase Intentions Through Green Brand Anthropomorphism Strategies: The Moderator Role of Facial Expression

This study uses an experimental comparison to analyze the effects of anthropomorphic strategies that use images with eyes (vs. those without eyes) on consumers' willingness to buy green products, as well as the mechanism of action. The study finds that concerning the anthropomorphic features of a product, anthropomorphic strategies containing images of eyes lead to more positive purchase intention for green products than those without images of eyes. Simultaneously, these green purchase intentions are mediated through the variable of green trust regardless of whether the anthropomorphic strategies feature eyes. Beyond this, the discussed effects are moderated when anthropomorphic strategies featuring different facial expressions are used. The findings of this study provide useful suggestions for green brand marketing strategies and management practices that use anthropomorphism.

The role of peer reward and punishment for public goods problems in a localized society

Cooperation in social dilemmas can be sustained if individuals are effectively rewarded or punished from peers within the group. However, as group size increases, we inevitably face localization, in which a global group is divided into several localized groups. In such societies, members can reward and punish only neighbors within the same localized group, while cooperation for social dilemmas should be solved through global group involvement. In this situation, the global group and the local group are not always equal in terms of welfare, and situations can arise in which cooperation is beneficial for the global group but not for the local group. We predict that in such a locally inefficient situation, peer reward and punishment cannot function to sustain global cooperation. We conducted an experiment in which 16 group members played a public goods game incorporating peer reward and punishment. We manipulated the range of peer reward and punishment (only local members/all global members) and payoff structure (locally efficient/locally inefficient). We found that high cooperation was not achieved and that peer reward and punishment did not function when, and only when, the group was divided into localized groups and the payoff structure was locally inefficient.

Children are sensitive to reputation when giving to both ingroup and outgroup members

Previous studies establish that reputation concerns play an important role in outgroup giving. However, it is unclear whether the same is true for ingroup giving, which by some accounts tends to be motivated by empathic concerns. To explore this question, we tested the extent to which 5 to 9-year-old children (Study 1: N = 164) and adults (Study 2: N = 80) shared resources with ingroup and outgroup members, either when being watched by an observer (where we expected reputation concerns to be salient) or in private (where we expected no effect of reputation concerns). We also assessed whether children and adults differ in their beliefs about which form of sharing (ingroup or outgroup giving) is nicer. Although we found that both children and adults exhibited an ingroup bias when sharing, there was no evidence in either group that reputation concerns were greater for outgroup members than for ingroup members. We also found that, in contrast to adults, children shared more resources when observed than in private. Additionally, children evaluated ingroup giving as nicer across different sharing scenarios, whereas adults identified outgroup giving as nicer when the two forms of giving were contrasted. These results are the first to suggest that reputational concerns influence children's sharing both with ingroup and outgroup members, and that children differ from adults in their reasoning about which form of group sharing is nicer.

How do socio-ecological factors shape culture? Understanding the process of micro-macro interactions

Socio-ecological environments produce certain psychological functions. that are adaptive for survival in each environment. Past evidence suggests that interdependence-related psychological features are prevalent in East Asian cultures partly due to the history of 'rice-crop farming' (versus herding) in those areas. However, it is unclear how and why certain functional behaviors required by the socio-ecological environment are sublimated to become cultural values, which are then transmitted and shared among people. In this paper, we conceptually review the works examining various macro sharing processes for cultural values, and focus on the use of multilevel analysis in elucidating the effect of both macro and individual level factors. Uchida et al.'s study (2019) suggests that collective activities at the macro level (community-level), which is required by a certain socio-ecological environment, promote interdependence not only among farmers but also non-farmers. The multilevel processes of how psychological characteristics are construed by macro factors will be discussed.

Comparison of Equity Preferences for Life Expectancy Gains: A Discrete Choice Experiment Among the Japanese and Korean General Public

BACKGROUND

Setting priorities for limited public resources has become a topic of heated discussion the world over. Assigning different weights for the health gains of different population groups allows for equity considerations in cost-effectiveness analysis. However, only a few empirical works have elicited the preferences of the general public.

OBJECTIVE

To compare the equity preferemce assigned by Japanese and Koreans.

METHODS

We conducted a Web-based survey in March 2013, including a discrete choice experiment, to elicit the equity preferences of the general public for the life expectancy gains of different population groups. We selected attributes and designed the experiment following Norman et al.'s study (Norman R, Hall J, Street D, Viney R. Efficiency and equity: a stated preference approach. Health Econ 2013;22:568-81). Accordingly, we analyzed preference for sex, smoking status, lifestyle, caring status, income, and age.

RESULTS

The Japanese assigned a higher preference for males (P < 0.001), nonsmokers (P < 0.001), those with lower income (P < 0.001), and carers (P < 0 .001), and they assigned a lower preference for those with a life expectancy of 60 years (P = 0.002) and 75-year-olds (P < 0.001). Koreans have the same patterns of preference for lower income (P < 0.001), caring (P < 0.001), and smoking status (P = 0.026). However, they prefer both sexes (P = 0.331) and different age groups equally. In both countries, respondents tend to prefer groups with characteristics similar to their own.

CONCLUSIONS

People from the two Asian developed countries, with universal health insurance, show different equity preferences. These may reflect the variations in cultural background and coverage of health care services.

No Evidence for the Watching-Eyes Effect on Human Impulsivity

People often become more altruistic when they think or feel that someone is watching them. Known as the “watching-eyes effect,” this is argued to be caused by the motivation to gain and maintain a positive social reputation as an altruistic individual (the “reputation seeking” mechanism). However, an alternative mechanism underlying the watching-eyes effect could be that people suppress their impulsive tendency to pursue benefit rather than increase their altruism, and this may lead to apparent increases in altruistic tendencies. This “suppressing impulsivity” mechanism is considered intrapersonal rather than socially mediated which is associated with “reputation seeking.” We examined whether the suppressing impulsivity mechanism would be associated with the watching-eyes effect by measuring participants’ impulsivity in the presence of watching-eyes stimuli. In a controlled experiment, we presented life-size pictures of human faces with a direct gaze on a monitor in front of participants taking part in a time-discounting task. Two types of faces, “in-group” (faces of participants’ classmates) and “out-group” (unfamiliar faces) were presented to examine the effect of social attribution. We used a flower picture as a control stimulus. In the time-discounting task, participants chose one of two options: a small amount of money that they could get immediately or a larger amount of money that they could get after a given time interval. The results showed no significant difference in participants’ time-discount rate regardless of the types of stimuli presented during the time-discount task. A post-task questionnaire confirmed that the participants were aware of the presented stimuli and revealed that they paid more attention to the in-group stimuli than to the out-group and flower stimuli, though this difference in attentive states had no effect on their impulsivity during the task. These results suggest that suppressing impulsivity is not a plausible mechanism for the watching-eyes effect. The null effect for the difference between the in-group and out-group stimuli also supports this conclusion. Thus, it is plausible that the watching-eyes effect is caused by the human tendency to boost social reputation and can be mediated by the social relationship with others.

Cheating in the name of others: Offering prosocial justifications promotes unethical behavior in young children

The current research examined whether young children engage in unethical behavior to a greater extent when they have a prosocial justification for doing so. Participants (3- and 5-year-olds, N = 240) played a guessing game in which they were tempted to cheat to win a prize after promising not to do so. In Study 1, children were randomly assigned to either an experimental prosocial condition in which they were told that the prize would be given to a child who was unable to play the game or a control condition in which they were told that they would get to keep the prize for themselves. The 5-year-olds, but not the 3-year-olds, were more likely to cheat in the prosocial condition than in the control condition. Studies 2a and 2b revealed that older children's tendency to engage in prosocial cheating was driven by their concern with signaling to others that they are prosocial. These findings suggest that the tendency to act unethically to benefit others emerges early in development and that this tendency may reflect children's interest in prosocial signaling.

Social identity shapes social valuation: evidence from prosocial behavior and vicarious reward

People frequently engage in more prosocial behavior toward members of their own groups, as compared to other groups. Such group-based prosociality may reflect either strategic considerations concerning one's own future outcomes or intrinsic value placed on the outcomes of in-group members. In a functional magnetic resonance imaging experiment, we examined vicarious reward responses to witnessing the monetary gains of in-group and out-group members, as well as prosocial behavior towards both types of individuals. We found that individuals' investment in their group-a motivational component of social identification-tracked the intensity of their responses in ventral striatum to in-group (vs out-group) members' rewards, as well as their tendency towards group-based prosociality. Individuals with strong motivational investment in their group preferred rewards for an in-group member, whereas individuals with low investment preferred rewards for an out-group member. These findings suggest that the motivational importance of social identity-beyond mere similarity to group members-influences vicarious reward and prosocial behavior. More broadly, these findings support a theoretical framework in which salient social identities can influence neural representations of subjective value, and suggest that social preferences can best be understood by examining the identity contexts in which they unfold.

The language of cooperation: shared intentionality drives variation in helping as a function of group membership

While we know that the degree to which humans are able to cooperate is unrivalled by other species, the variation humans actually display in their cooperative behaviour has yet to be fully explained. This may be because research based on experimental game-theoretical studies neglects fundamental aspects of human sociality and psychology, namely social interaction and language. Using a new optimal foraging game loosely modelled on the prisoner's dilemma, the egg hunt, we categorized players as either in-group or out-group to each other and studied their spontaneous language usage while they made interactive, potentially cooperative decisions. Both shared group membership and the possibility to talk led to increased cooperation and overall success in the hunt. Notably, analysis of players' conversations showed that in-group members engaged more in shared intentionality, the human ability to both mentally represent and then adopt another's goal, whereas out-group members discussed individual goals more. Females also helped more and displayed more shared intentionality in discussions than males. Crucially, we show that shared intentionality was the mechanism driving the increase in helping between in-group players over out-group players at a cost to themselves. By studying spontaneous language during social interactions and isolating shared intentionality as the mechanism underlying successful cooperation, the current results point to a probable psychological source of the variation in cooperation humans display.

Intergroup Biases in Fear-induced Aggression

Using a recently created preemptive strike game (PSG) with 176 participants, we investigated if the motivations of spite and/or fear promotes aggression that requires a small cost to the aggressor and imposes a larger cost on the opponent, and confirmed the earlier finding that fear does but spite does not promote intergroup aggression when the groups are characterized as minimal groups; additionally, the rate of intergroup aggression did not vary according to the group membership of the opponent. The PSG represents a situation in which both the motivations of spite and of fear can logically drive players to choose an option of aggression against an opponent. Participants decide whether or not to attack another participant, who also has the same capability. The decision is made in real time, using a computer. We discuss theoretical implications of our findings on the evolutionary foundations of intragroup cooperation and intergroup aggression. The evolutionary model of intergroup aggression, or the parochial altruism model, posits that intragroup cooperation and intergroup aggression have co-evolved, and thus it predicts both intragroup cooperation and intergroup aggression to emerge even in a minimal group devoid of a history of intergroup relationships. The finding that only intragroup cooperation but not intergroup aggression emerged in the minimal group experiments strongly suggests that intergroup aggression involves a psychological mechanism that is independent from that of intragroup cooperation. We further discuss the implications of these findings on real-world politics and military strategy.

Relationship between Salivary Oxytocin Levels and Generosity in Preschoolers

This study examined the association between salivary oxytocin (sOT) levels and generosity in preschoolers. Fifty preschoolers played two dictator games (DG) by deciding how to allocate 10 chocolates between themselves and another child, who was either from the same class as the participant (ingroup member), or an unknown child from another class (outgroup member). sOT levels were assessed in saliva collected from the children immediately prior to the DG tasks. While sOT levels were negatively associated with allocations made to both ingroup and outgroup members by boys, among girl sOT levels were positively related to allocations made to ingroup members, and unrelated to allocations made to outgroup members. These results suggest sex differences in the association between salivary oxytocin and generosity.

Effects of Eye Images and Norm Cues on Charitable Donation

Laboratory and field experiments have shown that people are more likely to be prosocial in the presence of watching eyes images. This “watching eyes effect” may be explained by the reputation-based partner choice model or a norm-compliance model suggesting that eye images elicit conformity to locally specific behavioral norms. A previous laboratory study that investigated the effects of local norms on charitable donations by using watching eye images and manipulating money visible in a collection box found that the presence of eye images significantly increased overall donations; however, the images did not make people more likely to conform to the apparent local norm. Here, we report the results of a field study examining the effects of watching eyes and the amount of money in transparent collection boxes on charitable giving in an izakaya (a Japanese-style tavern) setting. Contrary to the previous study, we found that the amount donated increased more under the large- than the small-norm treatment. The presence of eye images increased the overall amount donated but was more salient under the small-norm treatment. We found that participants were more likely to increase the amount of money in the box than to conform to the local norm of a small donation when the eye images were present. The results of this study suggest that an appropriate combination of eye images and normative information can alter people’s behavior without changing their economic incentives.

Audience effects: what can they tell us about social neuroscience, theory of mind and autism?

An audience effect arises when a person’s behaviour changes because they believe someone else is watching them. Though these effects have been known about for over 110 years, the cognitive mechanisms of the audience effect and how it might vary across different populations and cultures remains unclear. In this review, we examine the hypothesis that the audience effect draws on implicit mentalising abilities. Behavioural and neuroimaging data from a number of tasks are consistent with this hypothesis. We further review data suggest that how people respond to audiences may vary over development, personality factors, cultural background and clinical diagnosis including autism and anxiety disorder. Overall, understanding and exploring the audience effect may contribute to our models of social interaction, including reputation management and mentalising.

No evidence that a range of artificial monitoring cues influence online donations to charity in an MTurk sample

Monitoring cues, such as an image of a face or pair of eyes, have been found to increase prosocial behaviour in several studies. However, other studies have found little or no support for this effect. Here, we examined whether monitoring cues affect online donations to charity while manipulating the emotion displayed, the number of watchers and the cue type. We also include as statistical controls a range of likely covariates of prosocial behaviour. Using the crowdsourcing Internet marketplace, Amazon Mechanical Turk (MTurk), 1535 participants completed our survey and were given the opportunity to donate to charity while being shown an image prime. None of the monitoring primes we tested had a significant effect on charitable giving. By contrast, the control variables of culture, age, sex and previous charity giving frequency did predict donations. This work supports the importance of cultural differences and enduring individual differences in prosocial behaviour and shows that a range of artificial monitoring cues do not reliably boost online charity donation on MTurk.

[The characteristics of altruistic behavior that can sustain generalized exchange in a society composed of two groups]

Previous studies on generalized exchange have argued that group plays an important role in the emergence of cooperative society. To examine to what extent the role of a group is important, we conducted computer simulations in which players decide whether to give resources to members of a society composed of two groups. We examined whether a society consisting of any of the possible conceivable strategies (65536 strategies total) could resist invasion by an unconditional defector (ALLD) and an unconditional cooperator (ALLC). The results showed that universalist strategies, which give resources to both in-group members and out-group members equally, and in-group favoring strategies, which give resources to in-group members more than outgroup members, could resist invasion. Furthermore, we found that in-group favoring strategies could exclude ALLC from the circle of resource flow more easily than universalist strategies. These results imply that it may be necessary to employ an in-group favoring strategy that utilizes the group membership information of other people in order to maintain generalized exchange in a society composed of two groups.

The Rural-Urban Difference in Interpersonal Regret

The present research examined rural-urban differences in interpersonal regret. In Study 1, participants who grew up in rural areas reported stronger interpersonal regret than those who grew up in large cities. In Study 2, we conducted an experiment and found that participants who were assigned to imagine a rural life reported greater interpersonal regret than those who were assigned to imagine an urban life. Moreover, this rural-urban difference was mediated by the degree to which participants wrote about informal social control such as gossip and reputation concerns. Finally, in Study 3, we used the pictorial eye manipulation, which evokes a concern for informal social control, and found that participants from large cities who were exposed to the eyes reported more intense interpersonal regret than those who were not exposed to the eyes. Together, these studies demonstrate that informal social control is a key to understanding rural-urban differences in interpersonal regret.

It Depends Who Is Watching You: 3-D Agent Cues Increase Fairness

Laboratory and field studies have demonstrated that exposure to cues of intentional agents in the form of eyes can increase prosocial behavior. However, previous research mostly used 2-dimensional depictions as experimental stimuli. Thus far no study has examined the influence of the spatial properties of agency cues on this prosocial effect. To investigate the role of dimensionality of agency cues on fairness, 345 participants engaged in a decision-making task in a naturalistic setting. The experimental treatment included a 3-dimensional pseudo-realistic model of a human head and a 2-dimensional picture of the same object. The control stimuli consisted of a real plant and its 2-D image. Our results partly support the findings of previous studies that cues of intentional agents increase prosocial behavior. However, this effect was only found for the 3-D cues, suggesting that dimensionality is a critical variable in triggering these effects in a real-world settings. Our research sheds light on a hitherto unexplored aspect of the effects of environmental cues and their morphological properties on decision-making.

The influence of social preferences and reputational concerns on intergroup prosocial behaviour in gains and losses contexts

To what extent do people help ingroup members based on a social preference to improve ingroup members' outcomes, versus strategic concerns about preserving their reputation within their group? And do these motives manifest differently when a prosocial behaviour occurs in the context of helping another gain a positive outcome (study 1), versus helping another to avoid losing a positive outcome (study 2)? In both contexts, we find that participants are more prosocial towards ingroup (versus outgroup members) and more prosocial when decisions are public (versus private) but find no interaction between group membership and either anonymity of the decision or expected economic value of helping. Therefore, consistent with a preference-based account of ingroup favouritism, people appear to prefer to help ingroup members more than outgroup members, regardless of whether helping can improve their reputation within their group. Moreover, this preference to help ingroup members appears to take the form of an intuitive social heuristic to help ingroup members, regardless of the economic incentives or possibility of reputation management. Theoretical and practical implications for the study of intergroup prosocial behaviour are discussed.

Reputation Effects in Public and Private Interactions

We study the evolution of cooperation in a model of indirect reciprocity where people interact in public and private situations. Public interactions have a high chance to be observed by others and always affect reputation. Private interactions have a lower chance to be observed and only occasionally affect reputation. We explore all second order social norms and study conditions for evolutionary stability of action rules. We observe the competition between “honest” and “hypocritical” strategies. The former cooperate both in public and in private. The later cooperate in public, where many others are watching, but try to get away with defection in private situations. The hypocritical idea is that in private situations it does not pay-off to cooperate, because there is a good chance that nobody will notice it. We find simple and intuitive conditions for the evolution of honest strategies.

We study the evolution of cooperation based on reputation. This mechanism is called indirect reciprocity. In a world of binary reputations, people help a good individual but do not help a bad one. They also monitor their own reputation to receive reciprocation from others. We propose a novel model of indirect reciprocity where two types of interactions exist. In a public interaction your behavior is always observed by others. In a private interaction, your behavior is less likely to be observed. We study the competition between honest and hypocritical strategies. The former always help good individuals, whereas the latter do so only in private interactions. We describe conditions for the evolution of honest strategies.

The Watching-Eye Effect on Prosocial Lying

Evidence shows that people tend to behave prosocially when they are in the presence of images depicting eyes. There are two proximate causes of the eyes effect. One involves positive motivation to gain future reward and the other involves negative motivation to avoid violating a norm. Although several studies have suggested that positive motivation is a strong candidate, these studies were unable to distinguish between adherence to norms and prosocial behavior. We investigated the watching-eyes effect in an experimental setting to determine whether the tendency of humans to violate norms voluntarily could be understood as prosocial behavior. We compared the tendency to tell "prosocial lies" in the presence of a depiction of stylized eyes (eyes condition) with that involving no such depiction (control condition). Under the control condition, participants tended to tell lies that benefitted others, whereas the tendency toward prosocial lying disappeared under the eyes condition. This suggests that the desire to avoid violating norms by being honest is stronger than the desire to pursue a good reputation by demonstrating generosity when such violation might lead to serious costs.