Beauty matters: social preferences in a three-person ultimatum game

Distinct neural computations scale the violation of expected reward and emotion in social transgressions

Traditional decision-making models conceptualize humans as adaptive learners utilizing the differences between expected and actual rewards (prediction errors, PEs) to maximize outcomes, but rarely consider the influence of violations of emotional expectations (emotional PEs) and how it differs from reward PEs. Here, we conducted a fMRI experiment (n = 43) using a modified Ultimatum Game to examine how reward and emotional PEs affect punishment decisions in terms of rejecting unfair offers. Our results revealed that reward relative to emotional PEs exerted a stronger prediction to punishment decisions. On the neural level, the left dorsomedial prefrontal cortex (dmPFC) was strongly activated during reward receipt whereas the emotions engaged the bilateral anterior insula. Reward and emotional PEs were also encoded differently in brain-wide multivariate patterns, with a more sensitive neural signature observed within fronto-insular circuits for reward PE. We further identified a fronto-insular network encompassing the left anterior cingulate cortex, bilateral insula, left dmPFC and inferior frontal gyrus that encoded punishment decisions. In addition, a stronger fronto-insular pattern expression under reward PE predicted more punishment decisions. These findings underscore that reward and emotional violations interact to shape decisions in complex social interactions, while the underlying neurofunctional PEs computations are distinguishable.

Beauty and Social Interest Matter: Effects of Male's Facial Attractiveness, Vocal Attractiveness and Social Interest on Female's Decisions in Three-Person Games

Facial attractiveness, vocal attractiveness, and social interest influence two-person decision making. However, it remains unclear how these three factors jointly influence three-person bargaining. We investigated the impact of facial attractiveness, vocal attractiveness, and social interest on fairness decisions in a three-person ultimatum game and a third-party punishment dictator game. The results of the ultimatum game showed that in the condition of positive social interest, the acceptance rate of unfair/fair offers was higher when third players had attractive faces or attractive voices. Attractive faces of third players also increased acceptance rates of unfair/unfair offers than unattractive faces when third players expressed negative social interest. In the third-party punishment game, participants rated unfair allocations from unattractive-voice proposers with attractive faces (compared to unattractive faces) and proposers who expressed negative social interest (compared to positive social interest) as more reasonable. Regarding the punishment intentions, among the three factors, both the effect of vocal attractiveness and social interest were modulated by the combinations of the other two factors, while the effect of facial attractiveness remains robust across all conditions. These findings suggest that fairness decisions in three-person bargaining games are affected by beauty premium and social interest, while these effects vary across different decision contexts.

Height matters: An EEG study of the relative height disadvantage promoting third-party punishment

The study employed event-related potential (ERP), time-frequency analysis, and functional connectivity to comprehensively explore the influence of male's relative height on third-party punishment (TPP) and its underlying neural mechanism. The results found that punishment rate and transfer amount are significantly greater when the height of the third-party is lower than that of the recipient, suggesting that male's height disadvantage promotes TPP. Neural results found that the height disadvantage induced a smaller N1. The height disadvantage also evoked greater P300 amplitude, more theta power, and more alpha power. Furthermore, a significantly stronger wPLI between the rTPJ and the posterior parietal and a significantly stronger wPLI between the DLPFC and the posterior parietal were observed when third-party was at the height disadvantage. These results imply that the height disadvantage causes negative emotions and affects the fairness consideration in the early processing stage; the third-party evaluates the blame of violators and makes an appropriate punishment decision later. Our findings indicate that anger and reputation concern caused by height disadvantage promote TPP. The current study holds significance as it underscores the psychological importance of height in males, broadens the perspective on factors influencing TPP, validates the promoting effect of personal disadvantages on prosocial behavior, enriches our understanding of indirect reciprocity theory, and extends the application of the evolution theory of Napoleon complex.

Event-related potentials during the ultimatum game in people with symptoms of depression and/or social anxiety

Depression and social anxiety are common disorders that have a profound impact on social functioning. The need for studying the neural substrates of social interactions in mental disorders using interactive tasks has been emphasized. The field of neuroeconomics, which combines neuroscience techniques and behavioral economics multiplayer tasks such as the Ultimatum Game (UG), can contribute in this direction. We assessed emotions, behavior, and Event-Related Potentials in participants with depression and/or social anxiety symptoms (MD/SA, n = 63, 57 females) and healthy controls (n = 72, 67 females), while they played the UG. In this task, participants received fair, mid-value, and unfair offers from other players. Mixed linear models were implemented to assess trial level changes in neural activity. The MD/SA group reported higher levels of sadness in response to mid-value and unfair offers compared to controls. In controls, the Medial Frontal Negativity associated with fair offers increased over time, while this dynamic was not observed in the MD/SA group. The MD/SA group showed a decreased P3/LPP in all offers, compared to controls. These results indicate an enhanced negative emotional response to unfairness in the MD/SA group. Neural results reveal a blunted response over time to positive social stimuli in the MD/SA group. Moreover, between-group differences in P3/LPP may relate to a reduced saliency of offers and/or to a reduced availability of resources for processing incoming stimuli in the MD/SA group. Findings may shed light into the neural substrates of social difficulties in these disorders.

The Role of Sex in the Effect of Vocal Attractiveness on Ultimatum Game Decisions

The present research investigated the role of sex in the effect of vocal attractiveness on fairness judgment in a two-person Ultimatum Game. Each participant in the game decided whether to accept offers from a proposer who was either associated with an attractive or unattractive voice. The results showed that while participants were more likely to accept fair offers, they would also accept some unfair offers that were associated with an attractive voice. This effect of vocal attractiveness was more clearly shown by female participants, although all male and female participants took longer to make a decision when an attractive voice was associated with an offer, regardless of whether the voice was from the same sex or the opposite sex. Overall, the results inform the role of sex in the effect of vocal attractiveness and further confirm the beauty premium effect on economic bargaining, where people with an attractive voice would benefit.

How do decision makers evaluate advice from advisors with happy and angry expressions? A behavioural and ERP study

In the process of decision-making based on conferring with advisors, people are sensitive to advisors' emotional expressions. An advisor's expression is considered a type of feedback. The quick detection of motivational or valence significance of feedback has been associated with feedback-related negativity (FRN). In this study, we investigated how decision makers evaluated advice that was distant from the original estimate provided by advisors with different emotional expressions based on behavioural, FRN, and P300 data. The results showed that participants were more likely to modify their initial estimates based on advice from advisors with happy expressions than from advisors with angry expressions, regardless of whether it was near-distance advice or far-distance advice. When facing far-distance advice, FRN amplitudes in angry-expression conditions were significantly larger than in happy-expression conditions. When facing near-distance advice, there was no significant difference in the FRN amplitude between happy- and angry-expression conditions. P300 amplitudes were larger in near-distance conditions than in far-distance conditions. These findings suggest that, as a type of feedback with social information, the advisor's face will affect the decision maker's evaluation of the advice, with a happy face of the advisor serving as correct feedback and an angry face serving as incorrect feedback.

Do looks matter in supply chain contracting? An experimental study

We present results of an experiment designed to reveal the "face effect" on pricing behavior in a supply chain game. In particular, we study the variation in wholesale prices driven by subjective judgments of three facial traits-attractiveness, trustworthiness, and dominance-of a retailer's face and own appearance. Our experimental data suggest that the distributions of decisions in settings whether individuals see, or not see, retailers' faces are not equivalent. Furthermore, we find the complex dependencies between decision behaviors and facial traits. Subjective evaluations of facial traits, both self-reported and others, have a significant effect on the selected decisions.

The “beauty premium” effect of voice attractiveness of long speech sounds in outcome-evaluation event-related potentials in a trust game

Previous research suggested that people with attractive voices had an advantage in economic games, even if the voices were only presented for 400 ms. The present study investigated the influence of voice attractiveness on the cooperative trust behavior with longer exposure times to the voices. Event-related potentials (ERPs) were recorded during the feedback outcome evaluation. Participants heard a voice of the partner for 2,040 ms and decided whether to invest to the partner for a possibility to gain more money. The results showed that participants made more invest choices to the attractive partners, replicating the “beauty premium” effect of the attractive voices. Moreover, participants were more likely to invest to male partners. The ERP analysis for the outcome showed that the difference waves of feedback-related negativity (FRN) amplitude were smaller in the attractive voice condition than in the unattractive voice condition, suggesting that the rewarding effect of attractive voices weakened the frustrating feelings of the loss. In sum, the present study confirms that attractive voices with longer presentation durations facilitate cooperative behavior and modulate the processing of feedback evaluations.

I am entitled to it! Social power and context modulate disadvantageous inequity aversion

Previous research consistently indicated that social power influences one's fairness consideration. However, it is unclear how social power and context jointly affect inequity aversion and whether these processes would be manifested in brain activities. In this study, participants were randomly assigned into either high or low power condition and then took part in a modified ultimatum game (UG) as responders in both gain and loss contexts, with their event-related potentials (ERPs) recorded. Behavioral results showed that powerful participants were more likely to reject unfair offers in both contexts compared with powerless ones. In addition, powerful participants showed a more negative feedback-related negativity (FRN) loss-win difference wave (d-FRN) upon presentation of proposed offers compared with powerless participants only in the gain context. Interestingly, in a later time window, differences of P300 responses to proposed offers were modulated by social power in both gain and loss contexts. These results suggested that powerful people were more sensitive to fairness levels and FRN may manifest fairness consideration in a gain context, but not in a loss context. Meanwhile, P300 is sensitive to fairness considerations in both gain and loss contexts.

Beauty affects fairness: facial attractiveness alters neural responses to unfairness in the ultimatum game

Human faces consist of rich information for social interactions and facial attractiveness is a key dimension affecting social decisions. Previous studies have indicated that human players are less likely to refuse an unfair offer from proposers with high facial attractiveness in the Ultimatum Game (UG). However, the neural mechanisms underlying such beauty premium effect remain unclear. In this study, we used functional magnetic resonance imaging (fMRI) and examined the effects of facial attractiveness on brain responses to fair and unfair offers in the UG. Behavioral data showed that subjects were overall prone to refuse unfair offers across conditions but were more likely to accept unfair offers from higher facial attractive proposers than those from lower facial attractive proposers. Imaging data showed that unfair offers induced greater activity in the anterior insula and medial prefrontal cortex (MePFC) compared to those in fair offers condition for both high and low facial attractive proposers. Moreover, the acceptance rate of unfair offers positively correlated with the MePFC activity for high facial attractive proposers and negatively correlated with the anterior insula activity for low facial attractive proposers. These findings suggest that facial attractiveness modulates brain responses to unfairness through altering the roles of emotion and cognitive motivation in social interactions.

Vocal Attractiveness Matters: Social Preferences in Cooperative Behavior

Research has shown the phenomenon that "what sounds beautiful is good" is a stereotype. It is not clear whether vocal attractiveness affects social decision-making in economic games. Using a modified trust game task, we investigated the neural mechanism of the influence of vocal attractiveness on cooperative decision-making. Participants first heard the voice (attractive or unattractive) of the partner. They had enough time to decide whether to cooperate with the partner for a chance to earn monetary rewards. The behavioral results showed that participants made more invest choices in the attractive partner condition, and they were more likely to cooperate with the female partners in the unattractive voice condition. The event-related potential (ERP) analysis for voice stimuli showed that attractive voices induced larger N1 amplitude than unattractive voices only in the male voice condition. And female voices elicited smaller N1 and larger P2 amplitudes than male voices in both the attractive and unattractive voices condition. A larger P3 amplitude was evoked by female voices and attractive voices. In addition, a more positive late positive complex (LPC) was induced by male voices and attractive voices. This study suggested that attractive voices facilitated cooperative behavior, providing evidence for the "beauty premium" effect of the attractive voices. Moreover, participants were more likely to cooperate with female partners. In the early stage, gender information and male vocal attractiveness were processed automatically, suggesting that male vocal attractiveness was processed preferentially than the female voice. In the late stage, participants allocated attention to both male and female vocal attractiveness.

Electrophysiological Markers of Fairness and Selfishness Revealed by a Combination of Dictator and Ultimatum Games

Individual behavior during financial decision making is motivated by fairness, but an unanswered question from previous studies is whether particular patterns of brain activity correspond to different profiles of fairness. Event Related Potentials (ERPs) were recorded from 39 participants who played the role of allocators in a Dictator Game (DG) and responders in an Ultimatum Game (UG). Two very homogeneous groups were formed by fair and selfish individuals. At fronto-central cortical sites, the latency of ERP early negativity (N1) was 10 ms shorter in selfish participants than in fair participants. In fair DG players, the subsequent positive wave P2 suggested that more cognitive resources were required when they allocated the least gains to the other party. P2 latency and amplitude in the selfish group supported the hypothesis that these participants tended to maximize their profit. During UG, we observed that medial frontal negativity (MFN) occurred earlier and with greater amplitude when selfish participants rejected less favorable endowment shares. In this case, all players received zero payoffs, which showed that MFN in selfish participants was associated with a spiteful punishment. At posterior-parietal sites, we found that the greater the selfishness, the greater the amplitude of the late positive component (LPC). Our results bring new evidence to the existence of specific somatic markers associated with the activation of distinct cerebral circuits by the evaluation of fair and unfair proposals in participants characterized by different expressions of perceived fairness, thus suggesting that a particular brain dynamics could be associated with moral decisions.

The benefits of beauty – Individual differences in the pro-attractiveness bias in social decision making

While there already is a huge body of research examining the advantages and disadvantages of physical attractiveness in social and economic decisions, little research has been made to explore the role of individual differences in social decision-making with regard to beauty. To close this scientific gap, we conducted a multiparadigm online study (N = 210; 52% females) in which participants were asked to make decisions in four different economic games facing differently attractive counterparts. Additionally, the personality trait agreeableness was assessed to test for individual differences in decision-making. In exploratory analyses, we also assessed which facet of agreeableness is the most appropriate to predict individual differences in the various economic games. In the study, we were able to replicate the finding of a beauty premium and a plainness penalty but did not find any support for the idea of a beauty penalty. Furthermore, evidence for an opposite-sex advantage was found, which was greater when men were facing women than the other way around. While agreeableness as an overall trait influenced decision making across various paradigms, interactions of distinct facets of agreeableness with the partners’ attractiveness remain heterogeneous and ambiguous. This underlines the importance of integrating the specificity of certain traits in experimental research and the necessity of combining them with different social situations.

Me first: Neural representations of fairness during three-party interactions

One hallmark of human morality is a deep sense of fairness. People are motivated by both self-interest and a concern for the welfare of others. However, it remains unclear whether these motivations rely on similar neural computations, and the extent to which such computations influence social decision-making when self-fairness and other-fairness motivations compete. In this study, two groups of participants engaged in the role of responder in a three-party Ultimatum Game while being scanned with functional MRI (N = 32) or while undergoing high-density electroencephalography (N = 40). In both studies, participants accepted more OtherFair offers when they themselves received fair offers. Though SelfFairness was reliably decoded from scalp voltages by 170 ms, and from hemodynamic responses in right insula and dorsolateral prefrontal cortex, there was no overlap between neural representations of fairness for self and for other. Distinct neural computations and mechanisms seem to be involved when making decisions about fairness in three-party contexts, which are anchored in an egocentric, self-serving bias.

Neural time course and brain sources of facial attractiveness vs. trustworthiness judgment

Prior research has shown that the more (or less) attractive a face is judged, the more (or less) trustworthy the person is deemed and that some common neural networks are recruited during facial attractiveness and trustworthiness evaluation. To interpret the relationship between attractiveness and trustworthiness (e.g., whether perception of personal trustworthiness may depend on perception of facial attractiveness), we investigated their relative neural processing time course. An event-related potential (ERP) paradigm was used, with localization of brain sources of the scalp neural activity. Face stimuli with a neutral, angry, happy, or surprised expression were presented in an attractiveness judgment, a trustworthiness judgment, or a control (no explicit social judgment) task. Emotional facial expression processing occurred earlier (N170 and EPN, 150-290 ms post-stimulus onset) than attractiveness and trustworthiness processing (P3b, 400-700 ms). Importantly, right-central ERP (C2, C4, C6) differences reflecting discrimination between "yes" (attractive or trustworthy) and "no" (unattractive or untrustworthy) decisions occurred at least 400 ms earlier for attractiveness than for trustworthiness, in the absence of LRP motor preparation differences. Neural source analysis indicated that facial processing brain networks (e.g., LG, FG, and IPL-extending to pSTS), also right-lateralized, were involved in the discrimination time course differences. This suggests that attractiveness impressions precede and might prime trustworthiness inferences and that the neural time course differences reflect truly facial encoding processes.

Does dental trauma influence the social judgment and motivation to seek dental treatment by children and adolescents? Development, validation, and application of an instrument for the evaluation of traumatic dental injuries and their consequences

BACKGROUND

One's smile clearly plays a significant role in the perception and judgment that others have of one's appearance and personality.

AIM

We sought to develop and validate a questionnaire related to the social judgment of children and adolescents and to evaluate, through its application, the perceptions and judgment of children and adolescents regarding their view of different traumatic dental injuries and their consequences (TDIs-Cs) as well as the motivation to seek dental treatment.

DESIGN

The aspects of acceptability, discriminative properties, internal consistency, test-retest reliability, and construct validity were evaluated in the developed questionnaire. A cross-sectional study was conducted involving 100 boys and girls aged 10-15 years. Images of an adolescent male and female were either manipulated or not (control) to create different types of TDI-C (eg, enamel fracture, enamel and dentin fracture, crown colour change, and tooth loss/avulsion). These images were analysed by the participants, using a previously validated questionnaire with a six-positive-point and six-negative-point scale, in relation to their social physical and psychosocial characteristics. The data were analysed with the Friedman, Wilcoxon, and Mann-Whitney tests (P < 0.05).

RESULTS

The developed questionnaire presented high acceptability, strong discriminative properties, satisfactory internal consistency, and satisfactory test-retest reliability, but weak construct validity. The presence of TDI-C had a negative effect on all characteristics evaluated (P < 0.001). Tooth loss had the highest level of rejection. Additionally, the presence of TDI-C had a greater negative impact on the aspects of 'starting fights', 'being given a nickname', and 'being ashamed to smile' in males than in females (P < 0.05). Children and adolescents with TDI-C were judged as needing to seek dental treatment (P < 0.001).

CONCLUSION

The questionnaire developed showed properties of validity and reliability in its administration in a child and adolescent population. TDIs-Cs have a negative influence on the social judgment of children and adolescents.

The impact of advice distance on advice taking: Evidence from an ERP study

To use ERPs to investigate the impact of advice distance on advice taking in the Judge-Advisor System (JAS) paradigm, behavioural and ERP data were recorded from 20 subjects. The behavioural discrepancies and EEG characteristics of advice taking, as affected by the advice distances, were compared. The results showed that the relationship between the modification rate of a decision maker's initial estimation and the advice distance exhibited an inverse U-shaped curve. During the advice evaluation stage, different advice distances induced the feedback-related negativity (FRN) and subsequent P300 components. The amplitude of the FRN increased as the advice distance increased, while the amplitude of P300 in the zero distance condition was significantly larger than those in the intermediate and far distance conditions. These findings indicate that the advice evaluation process of a decision maker is related to conflict perception, prediction error and motivational or affective significance.

Hello handsome! Male's facial attractiveness gives rise to female's fairness bias in Ultimatum Game scenarios-An ERP study

The current study delineated how male proposers’ facial attractiveness affect female responders’ fairness considerations and their subsequent decision outcome during the Ultimatum Game (UG). Event Related Potentials (ERPs) were recorded from 17 female subjects, who played the role as responders and had to decide whether to accept offers from either attractive or unattractive male proposers. Behavioral data (Acceptance Ratio and Response time) revealed that, more offers were accepted from attractive-face conditions; subjects typically responded quicker to unfair offers from unattractive proposers as compared with slower to unfair offers from attractive proposers. The ERP data demonstrated similar N2 amplitudes elicited by both attractive and unattractive faces, and a larger early frontal LPP elicited by the attractive faces compared with unattractive ones, but no significant differences of both late posterior LPP and typical parietal LPP amplitudes were observed between these two face conditions, which was different from our previous study with similar paradigm but male participants. The results suggest that, in comparison to males, females might not experience the potential attention bias towards unattractive opposite-sex faces and are less likely to possess an enhanced processing and evaluation of those faces. This phenomenon might be explained by endogenous gender differences in mate preference. The feedback-related negativity (FRN) and P300 responses during an offer presentation were further measured in both attractive-face and unattractive-face conditions and the results demonstrated that the amplitudes elicited by fair and unfair offers were not statistically different in the former condition, but were different in the latter condition. More specifically, unfair offers generated larger FRN and smaller P300 than fair ones in the unattractive-face condition. Findings suggest that, although females tend to possess less salient evaluation of male’s facial attractiveness, the attractiveness of male proposers would still attenuate female responders’ fairness consideration during the UG.

Neural Process of the Preference Cross-category Transfer Effect: Evidence from an Event-related Potential Study

In business practice, companies prefer to find highly attractive commercial spokesmen to represent and promote their products and brands. This study mainly focused on the investigation of whether female facial attractiveness influenced the preference attitudes of male subjects toward a no-named and unfamiliar logo and determined the underlying reasons via neuroscientific methods. We designed two ERP (event-related potential) experiments. Experiment 1 comprised a formal experiment with facial stimuli. The purpose of experiment 2 was to confirm whether the logos that were used did not present a significant difference for the subjects. According to the behavioural results of experiment 1, when other conditions were not significantly different, the preference degree of the logos correlated with attractive female faces was increased compared with the logos correlated with unattractive faces. Reasons to explain these behavioural phenomena were identified via ERP measures, and preference cross-category transfer mainly caused the results. Additionally, the preference developed associated with emotion. This study is the first to report a novel concept referred to as the “Preference Cross-Category Transfer Effect”. Moreover, a three-phase neural process of the face evaluation subsequently explained how the cross-category transfer of preference occurred and influenced subject preference attitude toward brand logos.

The Influence of Counterfactual Comparison on Fairness in Gain-Loss Contexts

Fairness perceptions may be affected by counterfactual comparisons. Although certain studies using a two-player ultimatum game (UG) have shown that comparison with the proposers influences the responders' fairness perceptions in a gain context, the effect of counterfactual comparison in a UG with multiple responders or proposers remains unclear, especially in a loss context. To resolve these issues, this study used a modified three-player UG with multiple responders in Experiment 1 and multiple proposers in Experiment 2 to examine the influence of counterfactual comparison on fairness-related decision-making in gain and loss contexts. The two experiments consistently showed that regardless of the gain or loss context, the level of inequality of the offer and counterfactual comparison influenced acceptance rates (ARs), response times (RTs), and fairness ratings (FRs). If the offers that were received were better than the counterfactual offers, unequal offers were more likely to be accepted than equal offers, and participants were more likely to report higher FRs and to make decisions more quickly. In contrast, when the offers they received were worse than the counterfactual offers, participants were more likely to reject unequal offers than equal offers, reported lower FRs, and made decisions more slowly. These results demonstrate that responders' fairness perceptions are influenced by not only comparisons of the absolute amount of money that they would receive but also specific counterfactuals from other proposers or responders. These findings improve our understanding of fairness perceptions.

Children's perceptions of smile esthetics and their influence on social judgment

OBJECTIVE

To define a threshold of acceptance of smile esthetics for children and adolescents.

MATERIALS AND METHODS

A systematic search in the medical literature (PubMed, PubMed Central, National Library of Medicine's Medline, Embase, Cochrane Central Register of Controlled Clinical Trials, Web of Knowledge, Scopus, Google Scholar, and LILACs) was performed to identify all peer-reviewed papers reporting data regarding the evaluation of children's and adolescents' perceptions of dental esthetic factors. The search was conducted using a research strategy based on keywords such as "children," "adolescents," "smile aesthetics perception," "smile aesthetics evaluation." Studies analyzing smile esthetics involving at least 10 observers younger than 18 years of age were selected.

RESULTS

Among the 1667 analyzed articles, five studies were selected for the final review process. No study included in the review analyzed perception of smile anomalies in a quantitative or qualitative way, thus no threshold was identified for smile features. Among the analyzed samples, unaltered smiles were always significantly associated with better evaluation scores when compared with altered smiles.

CONCLUSIONS

Smile esthetics influence social perception during childhood and adolescence. However, thresholds of smile esthetic acceptance in children and adolescents are still not available.