Facial appearance affects voting decisions

The motivations and reputational consequences of spreading conspiracy theories

Some people deliberately spread conspiracy theories. What are the reputational benefits and costs of doing so? The Adaptive-Conspiracism hypothesis proposes that it pays to be vigilant against possible conspiracies, especially in case of intergroup threat. Those who spread conspiracy theories may therefore be seen as valuable group members. Few studies have focused on the reputational impact of spreading a conspiracy theory. We conducted five studies (NPilot = 303; NStudy1 = 388; NStudy2 = 560; NStudy3 = 391; NStudy4 = 373) where participants rated a conspiracy spreader (vs. a neutral person) on a range of personality traits in different intergroup contexts. The results indicated that conspiracy spreaders were consistently perceived as more dominant and less warm than people making non-conspiratorial claims about certain events. Moreover, intergroup conflict attenuated the negative effects of spreading conspiracy theories on competence and warmth. These findings support the notion that besides drawbacks, spreading conspiracy theories can have benefits for the spreader's reputation, particularly during an intergroup conflict.

Effects of masculinity vs. femininity on competence judgement of politician faces and election outcome prediction

First impressions of politician faces can be effective in predicting election outcomes, based on perceived competence from candidate photographs. However, it remains unclear whether such effects arose from facial features or other non-facial information present in the photographs (e.g. hairstyles, clothes, or poses). In four pre-registered studies, participants completed two tasks in a counter-balanced order: rating competence of individually presented faces and predicting election outcome of each pair of winner and runner-up faces. We examined competence judgment and election outcome prediction on faces from male politicians depicted on original portraits (Experiment 1), or on computer-generated faces with facial features extracted from the portraits (Experiment 2). The faces were then either masculinized or feminized (Experiments 3 and 4). We found that competence ratings were significantly higher for winners than runners-up and that winners were more likely predicted to win the elections than runners-up in all but Experiment 4, where faces of the winners were feminized and faces of the runners-up were masculinized. Regardless of facial feature changes, correlations were found between competence ratings and election outcome prediction. These findings suggest that facial features are critical for evaluating competence and predicting election outcome, and that masculine features may enhance stereotypical leadership impressions.

First Impressions: Setting the Stage for Better Relationships

Background:

There is no consensus on the postoperative outcomes of tongue reconstruction. Therefore, the authors developed a novel risk model for predicting dysphagia after tongue reconstruction.

Methods:

This retrospective study was conducted by the Oral Pharyngeal Esophageal Operation and Reconstruction Analytical, or OPERA, group across 31 cancer centers and university hospitals in Japan. A total of 532 patients [390 (73.3%) men and 142 (26.7%) women; median age at surgery, 60 years (range, 15 to 88 years)] who were diagnosed with oral tongue squamous cell carcinoma and underwent tongue reconstruction following glossectomy between 2009 and 2013 were included. Independent risk factors were identified using univariate regression analysis and converted to a binary format for multivariate analysis. An integer value was assigned to each risk factor to calculate a total score capable of quantifying the risk of feeding tube dependence.

Results:

Overall, 54 patients (10.2%) required a feeding tube at the time of evaluation. Predictive factors for feeding tube dependence were advanced age, lower American Society of Anesthesiologists physical status, low body mass index, lower serum albumin, comorbid hypertension and diabetes, extended tongue defect, resection beyond the tongue, laryngeal suspension, postoperative radiation therapy, and no functional teeth. In multivariate logistic regression analysis, age greater than or equal to 58.5 years, postoperative radiation therapy, wider tongue defect, and body mass index less than 21.27 kg/m2 earned 6, 4, 3, and 2 points, respectively, for a maximum total score of 15.

Conclusion:

The authors’ risk model provides a mathematical tool for estimating the individual risk of postoperative feeding tube dependence before tongue reconstruction.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Risk, III.

Complex faces and naïve machines A commentary on facial perceptions of age, gender, and leader preferences in the age of AI

Tasks driven by artificial intelligence (AI), such as evaluating video job interviews, rely on facial recognition systems for decision-making. Therefore, it is extremely important that the science behind this technology is continually advancing. If not, visual stereotypes, such as those associated with facial age and gender, will lead to dangerous misapplications of AI.

Preference for leaders with high and low facial width-to-height ratios: moderating roles of political ideology and voting context

BACKGROUND

It has been argued that human ancestors evolved greater sensitivity to certain traits that signal dominance in potential leaders. From this perspective, modern voters still favor certain physical characteristics during political elections. Indeed, previous studies have shown that voters prefer dominant candidates, especially when primed with wartime scenarios, and with conservative voters being more likely to choose a dominant leader. Because facial width-to-height ratio (fWHR) was found to be positively associated with perceived dominance, we sought to investigate the effect of fWHR on leader preference by taking into an account voting context and voters' political ideology.

PARTICIPANTS AND PROCEDURE

A total of 148 participants took part in two online experiments in which we manipulated standardized facial images to represent faces with low and high fWHR. Furthermore, we assessed participants' political ideology and asked them to rate the extent to which faces with low and high fWHR looked like leaders during wartime and peacetime scenarios.

RESULTS

Preference for leaders with high fWHR was positively related to participants' political ideology, but only in a wartime scenario, suggesting that the more conservative participants were, the higher was their preference for leaders with high fWHR. This is consistent with the notion that preferences for dominant-looking leaders vary as a function of the contextual (voting context) and individual differences (political ideology).

CONCLUSIONS

The present findings provide new evidence for the contribution of fWHR in leader preference and significantly adds to the results of previous research demonstrating the roles of voters' political ideology and politicians' physical characteristics in perceiving leadership abilities.

Gender and Context-Specific Effects of Vocal Dominance and Trustworthiness on Leadership Decisions

Objective

The evolutionary-contingency hypothesis, which suggests that preferences for leaders are context-dependent, has found relatively consistent support from research investigating leadership decisions based on facial pictures. Here, we test whether these results transfer to leadership decisions based on voice recordings. We examined how dominance and trustworthiness perceptions relate to leadership decisions in wartime and peacetime contexts and whether effects differ by a speaker’s gender. Further, we investigate two cues that might be related to leadership decisions, as well as dominance and trustworthiness perceptions: voice pitch and strength of regional accent.

Methods

We conducted a preregistered online study with 125 raters and recordings of 120 speakers (61 men, 59 women) from different parts in Germany. Raters were randomly distributed into four rating conditions: dominance, trustworthiness, hypothetical vote (wartime) and hypothetical vote (peacetime).

Results

We find that dominant speakers were more likely to be voted for in a wartime context while trustworthy speakers were more likely to be voted for in a peacetime context. Voice pitch functions as a main cue for dominance perceptions, while strength of regional accent functions as a main cue for trustworthiness perceptions.

Conclusions

This study adds to a stream of research that suggests that (a) people’s voices contain important information based on which we form social impressions and (b) we prefer different types of leaders across different contexts. Future research should disentangle effects of gender bias in leadership decisions and investigate underlying mechanisms that influence how people’s voices contribute to achieving social status.

Partisan discrimination without explicit partisan cues

Much research has demonstrated that Democrats and Republicans use information about party affiliation to discriminate against one another. However, we know little about how people gain the necessary information about other people’s partisanship to engage in discriminatory behavior. We explore whether people perceive partisanship when shown only images of faces, and whether they then use these perceptions to engage in partisan discrimination. We find that they do. Using two studies we show that the partisan perceptions people derive from seeing images of faces influence discrimination of job applicants, and propensities to engage is a wide range of social interactions. People appear to be making judgements about partisanship using only facial appearance, and are willing act on that perception. The implication of this finding is that partisan discrimination is likely widespread, and does not require the explicit communication of partisan affiliations.

Set the tone: Trustworthy and dominant novel voices classification using explicit judgement and machine learning techniques

Prior research has established that valence-trustworthiness and power-dominance are the two main dimensions of voice evaluation at zero-acquaintance. These impressions shape many of our interactions and high-impact decisions, so it is crucial for many domains to understand this dynamic. Yet, the relationship between acoustical properties of novel voices and personality/attitudinal traits attributions remains poorly understood. The fundamental problem of understanding vocal impressions and relative decision-making is linked to the complex nature of the acoustical properties in voices. In order to disentangle this relationship, this study extends the line of research on the acoustical bases of vocal impressions in two ways. First, by attempting to replicate previous finding on the bi-dimensional nature of first impressions: using personality judgements and establishing a correspondence between acoustics and voice-first-impression (VFI) dimensions relative to sex (Study 1). Second (Study 2), by exploring the non-linear relationships between acoustical parameters and VFI by the means of machine learning models. In accordance with literature, a bi-dimensional projection comprising valence-trustworthiness and power-dominance evaluations is found to explain 80% of the VFI. In study 1, brighter (high center of gravity), smoother (low shimmers), and louder (high minimum intensity) voices reflected trustworthiness, while vocal roughness (harmonic to noise-ratio), energy in the high frequencies (Energy3250), pitch (Quantile 1, Quantile 5) and lower range of pitch values reflected dominance. In study 2, above chance classification of vocal profiles was achieved by both Support Vector Machine (77.78%) and Random-Forest (Out-Of-Bag = 36.14) classifiers, generally confirming that machine learning algorithms could predict first impressions from voices. Hence results support a bi-dimensional structure to VFI, emphasize the usefulness of machine learning techniques in understanding vocal impressions, and shed light on the influence of sex on VFI formation.

Why Warmth Matters More Than Competence: A New Evolutionary Approach

Multiple lines of evidence suggest that there are two major dimensions of social perception, often called warmth and competence, and that warmth is prioritized over competence in multiple types of social decision-making. Existing explanations for this prioritization argue that warmth is more consequential for an observer's welfare than is competence. We present a new explanation for the prioritization of warmth based on humans' evolutionary history of cooperative partner choice. We argue that the prioritization of warmth evolved because ancestral humans faced greater variance in the warmth of potential cooperative partners than in their competence but greater variance in competence over time within cooperative relationships. These each made warmth more predictive than competence of the future benefits of a relationship, but because of differences in the distributions of these traits, not because of differences in their intrinsic consequentiality. A broad, synthetic review of the anthropological literature suggests that these conditions were characteristic of the ecologies in which human social cognition evolved, and agent-based models demonstrate the plausibility of these selection pressures. We conclude with future directions for the study of preferences and the further integration of social and evolutionary psychology.

Sex bias in intergroup conflict and collective movements among social mammals: male warriors and female guides

Intergroup conflict is a major evolutionary force shaping animal and human societies. Males and females should, on average, experience different costs and benefits for participating in collective action. Specifically, among mammals, male fitness is generally limited by access to mates whereas females are limited by access to food and safety. Here we analyse sex biases among 72 species of group-living mammals in two contexts: intergroup conflict and collective movements. Our comparative phylogenetic analyses show that the modal mammalian pattern is male-biased participation in intergroup conflict and female-biased leadership in collective movements. However, the probability of male-biased participation in intergroup conflicts decreased and female-biased participation increased with female-biased leadership in movements. Thus, female-biased participation in intergroup conflict only emerged in species with female-biased leadership in collective movements, such as in spotted hyenas and some lemurs. Sex differences are probably attributable to costs and benefits of participating in collective movements (e.g. towards food, water, safety) and intergroup conflict (e.g. access to mates or resources, risk of injury). Our comparative review offers new insights into the factors shaping sex bias in leadership across social mammals and is consistent with the 'male warrior hypothesis' which posits evolved sex differences in human intergroup psychology. This article is part of the theme issue 'Intergroup conflict across taxa'.

Changes to Eye Whiteness and Eyelid/Brow Position With Topical Oxymetazoline in Aesthetic Patients

BACKGROUND

Oxymetazoline hydrochloride 0.1% ophthalmic solution has recently been approved in the United States for the treatment of ptosis.

OBJECTIVES

The aim of this study was to assess the upper and lower eyelid position as well as the brow position and the color of the sclera following the ophthalmic administration of oxymetazoline hydrochloride 0.1%.

METHODS

In this prospective cohort study, consecutive patients presenting with ptosis received topical oxymetazoline 0.1%. The primary outcome was measurement of the upper eyelid height (margin-to-reflex distance 1 [MRD1]) and lower eyelid height (MRD2) relative to the center of pupil, along with assessment of brow height, measured on photographs at baseline and 2 hours after instillation of oxymetazoline. The secondary outcome was the assessment of the color of the sclera (eye whiteness) before and after treatment with a novel color space algorithm.

RESULTS

Twenty-nine patients participated in the study. The mean [SD] MRD1 at baseline was 2.3 [0.6] mm. At 2 hours following oxymetazoline treatment, the mean MRD1 significantly increased to 4.2 [0.9] mm (P < 0.01). The mean MRD2 also significantly increased from 5.3 [0.9] mm to 5.7 [1.0] mm (P < 0.01). Brow position did not change with treatment (P = 0.4). Following treatment, the eye sclera became significantly whiter, with a mean ΔEab (color change) of 9.7 [3.9], with 57 out of 58 eyes experiencing a significant change in color. A change of ΔEab ≥2 is considered visually perceptible to the human eye.

CONCLUSIONS

Within 2 hours of use, oxymetazoline significantly improves the size of the palpebral aperture (MRD1 + MRD2) and also makes the eye appear significantly whiter.

LEVEL OF EVIDENCE: 4

Deep models of superficial face judgments

We quickly and irresistibly form impressions of what other people are like based solely on how their faces look. These impressions have real-life consequences ranging from hiring decisions to sentencing decisions. We model and visualize the perceptual bases of facial impressions in the most comprehensive fashion to date, producing photorealistic models of 34 perceived social and physical attributes (e.g., trustworthiness and age). These models leverage and demonstrate the utility of deep learning in face evaluation, allowing for 1) generation of an infinite number of faces that vary along these perceived attribute dimensions, 2) manipulation of any face photograph along these dimensions, and 3) prediction of the impressions any face image may evoke in the general (mostly White, North American) population.

The diversity of human faces and the contexts in which they appear gives rise to an expansive stimulus space over which people infer psychological traits (e.g., trustworthiness or alertness) and other attributes (e.g., age or adiposity). Machine learning methods, in particular deep neural networks, provide expressive feature representations of face stimuli, but the correspondence between these representations and various human attribute inferences is difficult to determine because the former are high-dimensional vectors produced via black-box optimization algorithms. Here we combine deep generative image models with over 1 million judgments to model inferences of more than 30 attributes over a comprehensive latent face space. The predictive accuracy of our model approaches human interrater reliability, which simulations suggest would not have been possible with fewer faces, fewer judgments, or lower-dimensional feature representations. Our model can be used to predict and manipulate inferences with respect to arbitrary face photographs or to generate synthetic photorealistic face stimuli that evoke impressions tuned along the modeled attributes.

In the Face of Opportunities: Facial Structures of Scientists Shape Expectations of STEM Environments

Impressions of role leaders provide information about anticipated opportunities in a role, and these perceptions can influence attitudes about science, technology, engineering, and mathematics (STEM) pathways. Specifically, the facial structures of role leaders influenced perceived affordances of working with that person, such as the availability of communal and agentic opportunities (e.g., mentorship; achievement). STEM faculty with trustworthy (relative to dominant) faces were seen as valuing communal goals (Studies 1-3), and in turn, perceived as affording both communal and agentic opportunities in their research groups (Studies 2-3b). These heightened goal opportunities aligned with perceptions that trustworthy-faced advisors would enact more group-supportive behaviors (Study 2). Consequently, students anticipated fairer treatment and reported greater interest in labs directed by trustworthy- than dominant-faced leaders (Studies 3a-4a), even when images were accompanied by explicit information about leaders' collaborative behavior (Study 4b). The faces of leaders can thus function as the "face" of that role and the surrounding culture.

The powerful self: How social power and gender influence face perception

While ample evidence supports an association between power and dominance, little is still known about how temporary experiences of power influence the way people come to see themselves and others. The present research investigates the effect of social power on self- and other-face recognition, and examines whether gender modulates the direction of this effect. Male and female participants were induced to feel either powerful or powerless and had to recognize their own face and those of same-sex strangers from a series of images ranging from a dominant to a submissive version of the original. Results showed that males more frequently chose a dominant self-image under high power, whereas females selected a submissive self-image under low power. When presented with faces of same-sex targets female participants relied on low-power features (i.e., submissiveness) of the self in the perception of others (assimilation effect), whereas male participants more often selected a dominant image of strangers when feeling powerless (constrast effect). The effects of power did not extend to more deliberate judgments of dominance and likability, suggesting that respective biases in face recollection operated at an implicit level. This research underscores the cognitive and motivational underpinnings of power and related gender gaps in power attainment.

Perception of Emergent Leaders' Faces and Evolution of Social Cheating: Cross-Cultural Experiments

The aim of the present study was to investigate whether neutral faces of individuals with different propensities for leadership may convey information about their personal qualities, and are there impacts of sex, population and social environment on the facial perception. This study is based on a previous experiment ( Rostovtseva et al., 2022), where emergent leadership in the context of male group cooperation was investigated in Buryats (Mongolian population of Siberia). In the previous study three behavioural types of participants were revealed: non-leaders, prosocial leaders and leaders-cheaters, each having a set of distinguishing personality, communicative, and cooperative features. In the current study, three composite portraits representing different leadership qualities of Buryat men from the prior experiment were created. The composites were then scored on a number of traits by male and female Russian and Buryat independent raters (N = 435). The results revealed that ratings on masculinity, physical strength, dominance, competitiveness, and perceived leadership were positively correlated, while perceived trustworthiness was negatively associated with these traits. However, the composite portraits of actual leaders generally were scored as more trustworthy, masculine, and physically strong, with the prosocial leaders' portrait being perceived as healthier than others. Surprisingly, the composite of leaders-cheaters was scored as the most trustworthy and generous, and the least competitive than others. No significant effects of raters' sex, origin, or degree of familiarity with Mongolian appearance were revealed. We conclude that static facial morphology contributes to appearing trustworthy, which may allow exploitation of others.

I believe what I see: Impact of attire and academic degree on evaluation of personality traits of a politician

BACKGROUND

The image of a politician primes people to judge his/her personality traits. Voters are looking for such qualities as honesty, intelligence, friendliness, sincerity, and trustworthiness. Most studies, however, concentrate on the evaluation of faces, and only some take into account the candidate's attire.

PARTICIPANTS AND PROCEDURE

The research included 320 participants between 18 and 78 years. It aimed to assess whether the parliamentary candidate's attire affects voters' evaluation of his personality traits. A description of his program was also presented to determine whether it affected the candidate's evaluation. Participants observed four versions of a fictional candidate's election materials: the candidate dressed in a formal suit or dressed casually and dressed formally or casually but bearing a doctor's degree. We used a self-constructed questionnaire to evaluate selected traits of the candidate's character.

RESULTS

The findings revealed that participants believed an individual in casual wear to be more active, attractive, open to people and the world, friendly, honest, and reliable, and only more smart, and effective while dressed formally. Also, the academic degree proved to be of importance. Accordingly, the same person with a doctorate was additionally evaluated as competent, responsible when dressed casually, and responsible when wearing a suit. It confirms the assumption that the informal dress and academic degree are most influential. The program description proved to be of no significance.

CONCLUSIONS

Our study shows that the way the candidate was dressed affected the evaluation of his personality characteristics. The participants attributed the casually dressed candidate the traits expected from a politician.

The Ginevra de' Benci Effect: Competence, Morality, and Attractiveness Inferred From Faces Predict Hiring Decisions for Women

The present study examined the role of morality, competence, and attractiveness as perceived from faces in predicting hiring decisions for men and women. Results showed that for both female and male applicants, facial competence significantly predicted the hiring decision directly and indirectly, through the mediation of the overall impression. Decisions concerning female applicants were, however, significantly predicted by multiple dimensions-that is, facial morality, facial competence, and attractiveness-with the mediation of the overall impression. Facial competence was the only significant predictor of impression and, in turn, hiring decision about men. These findings resonate the motto Virtutem forma decorat, "Beauty adorns virtue," painted by Leonardo da Vinci on the reverse side of the portrait of Ginevra de' Benci, and suggest that women's chances of getting a job are less than those of men whenever they do not show a moral and competent and attractive face.

Pandemic Leadership: Sex Differences and Their Evolutionary-Developmental Origins

The COVID-19 pandemic has caused a global societal, economic, and social upheaval unseen in living memory. There have been substantial cross-national differences in the kinds of policies implemented by political decision-makers to prevent the spread of the virus, to test the population, and to manage infected patients. Among other factors, these policies vary with politicians' sex: early findings indicate that, on average, female leaders seem more focused on minimizing direct human suffering caused by the SARS-CoV-2 virus, while male leaders implement riskier short-term decisions, possibly aiming to minimize economic disruptions. These sex differences are consistent with broader findings in psychology, reflecting women's stronger empathy, higher pathogen disgust, health concern, care-taking orientation, and dislike for the suffering of other people-as well as men's higher risk-taking, Machiavellianism, psychopathy, narcissism, and focus on financial indicators of success and status. This review article contextualizes sex differences in pandemic leadership in an evolutionary framework. Evolution by natural selection is the only known process in nature that organizes organisms into higher degrees of functional order, or counteracts the unavoidable disorder that would otherwise ensue, and is therefore essential for explaining the origins of human sex differences. Differential sexual selection and parental investment between males and females, together with the sexual differentiation of the mammalian brain, drive sex differences in cognition and behavioral dispositions, underlying men's and women's leadership styles and decision-making during a global pandemic. According to the sexually dimorphic leadership specialization hypothesis, general psychobehavioral sex differences have been exapted during human evolution to create sexually dimorphic leadership styles. They may be facultatively co-opted by societies and/or followers when facing different kinds of ecological and/or sociopolitical threats, such as disease outbreaks or intergroup aggression. Early evidence indicates that against the invisible viral foe that can bring nations to their knees, the strategic circumspection of empathic feminine health "worriers" may bring more effective and humanitarian outcomes than the devil-may-care incaution of masculine risk-taking "warriors".

When do people prefer dominant over prestigious political leaders?

Previous research has sought to explain the rise of right-wing populist leaders in terms of the evolutionary framework of dominance and prestige. In this framework, dominance is defined as high social rank acquired via coercion and fear, and prestige is defined as high social rank acquired via competence and admiration. Previous studies have shown that right-wing populist leaders are rated as more dominant than non-populist leaders, and right-wing populist/dominant leaders are favoured in times of economic uncertainty and intergroup conflict. In this paper, we explore and critique this application of dominance-prestige to politics. First, we argue that the dominance-prestige framework, originally developed to explain inter-personal relationships within small-scale societies characterised by face-to-face interaction, does not straightforwardly extend to large-scale democratic societies which have frequent anonymous interaction and complex ingroup-outgroup dynamics. Second, we show that economic uncertainty and intergroup conflict predict a preference not only for dominant leaders, but also for prestigious leaders. Third, we show that perceptions of leaders as dominant or prestigious are not fixed, and depend on the political ideology of the perceiver: people view leaders who share their ideology as prestigious, and those who oppose their ideology as dominant, whether that ideology is liberal or conservative. Fourth, we show that political ideology is a stronger predictor than economic uncertainty of preference for Donald Trump vs Hillary Clinton in the 2016 US Presidential Election, contradicting previous findings that link Trump's success to economic uncertainty. We conclude by suggesting that, if economic uncertainty does not directly affect preferences for right-wing populist leaders, other features of their discourse such as higher emotionality might explain their success.

Visceral politics: a theoretical and empirical proof of concept

While the study of affect and emotion has a long history in psychological sciences and neuroscience, the very question of how visceral states have come to the forefront of politics remains poorly understood. The concept of visceral politics captures how the physiological nature of our engagement with the social world influences how we make decisions, just as socio-political forces recruit our physiology to influence our socio-political behaviour. This line of research attempts to bridge the psychophysiological mechanisms that are responsible for our affective states with the historical socio-cultural context in which such states are experienced. We review findings and hypotheses at the intersections of life sciences, social sciences and humanities to shed light on how and why people come to experience such emotions in politics and what if any are their behavioural consequences. To answer these questions, we provide insights from predictive coding accounts of interoception and emotion and a proof of concept experiment to highlight the role of visceral states in political behaviour. This article is part of the theme issue 'The political brain: neurocognitive and computational mechanisms'.

Algorithmic and human prediction of success in human collaboration from visual features

As groups are increasingly taking over individual experts in many tasks, it is ever more important to understand the determinants of group success. In this paper, we study the patterns of group success in Escape The Room, a physical adventure game in which a group is tasked with escaping a maze by collectively solving a series of puzzles. We investigate (1) the characteristics of successful groups, and (2) how accurately humans and machines can spot them from a group photo. The relationship between these two questions is based on the hypothesis that the characteristics of successful groups are encoded by features that can be spotted in their photo. We analyze >43K group photos (one photo per group) taken after groups have completed the game—from which all explicit performance-signaling information has been removed. First, we find that groups that are larger, older and more gender but less age diverse are significantly more likely to escape. Second, we compare humans and off-the-shelf machine learning algorithms at predicting whether a group escaped or not based on the completion photo. We find that individual guesses by humans achieve 58.3% accuracy, better than random, but worse than machines which display 71.6% accuracy. When humans are trained to guess by observing only four labeled photos, their accuracy increases to 64%. However, training humans on more labeled examples (eight or twelve) leads to a slight, but statistically insignificant improvement in accuracy (67.4%). Humans in the best training condition perform on par with two, but worse than three out of the five machine learning algorithms we evaluated. Our work illustrates the potentials and the limitations of machine learning systems in evaluating group performance and identifying success factors based on sparse visual cues.

Facial Appearance and Electoral Success of Male Italian Politicians

Abstract. People rely on the facial appearance of political candidates when voting. Here, we examine whether the perceived competence, trustworthiness, and attractiveness of male Italian mayoral candidates ( n = 150) predict their electoral success. Building on situational leadership theory, we also examine whether associations between apparent traits and electoral success are moderated by contextual factors. Specifically, we test whether trustworthy-looking politicians are more successful in Southern Italy where political corruption is a more salient issue. Across three preregistered studies ( N = 470), we find that attractive-looking candidates were more successful. Perceived competence and trustworthiness were not consistently associated with electoral success. Moreover, we do not find evidence that regional variation in corruption moderates the success of trustworthy-looking politicians.

Geometric morphometric analysis of Japanese female facial shape in relation to psychological impression space

Facial appearance has essential consequences in various social interactions. Previous studies have shown that although people can perceive a variety of impressions from a face, these impressions may form from a relatively small number of core dimensions in the psychological impression space (e.g., valence and dominance). However, few studies have thus far examined which facial shape features contribute to perceptions of the core trait impression dimensions for Asian female faces. This study aimed to identify the commonalities between various facial impressions of Japanese female faces and determine the facial shape components associated with such impressions by applying geometric morphometric (GMM) analysis. In Experiment 1 (Modeling study), Japanese female faces were evaluated in terms of 18 trait adjectives that are frequently used to describe facial appearance in daily life. We found that Japanese female facial appearance is indeed evaluated mainly on the valence and dominance dimensions. In Experiment 2 (Validation study), we confirmed that all the trait impressions were quantitatively manipulated by transforming the facial shape features associated with valence and dominance. Our results provide evidence that various facial impressions derived from these two underlying dimensions can be quantitatively manipulated by transforming facial shape using the GMM techniques.

An Experimental Examination of Demand-Side Preferences for Female and Male National Leaders

Females constitute a far smaller proportion of political leaders than their proportion in the general population. Leading demand- and supply side explanations for this phenomenon account for some of the variance but leave a great deal unexplained. In an effort to account for additional variance, this research evaluates the issue informed by the biological theory of evolution by natural selection, a foundational explanation for the diversity and function of living organisms. It experimentally assesses how varying types of inter- and intragroup threat-a recurring ancestral problem-affect demand for female and male national leaders. This work analyzes data collected from individuals (N = 826) in the U.S. during the 2012 Cooperative Congressional Election Study. The results suggest the predominant preference for male over female leaders in some contexts may be the non-adaptive and non-functional but lingering outcome of an adaptive preference for physically formidable allies that was shaped by natural selection in ancestral environments.

The Influence of Each Facial Feature on How We Perceive and Interpret Human Faces

Facial information is processed by our brain in such a way that we immediately make judgments about, for example, attractiveness or masculinity or interpret personality traits or moods of other people. The appearance of each facial feature has an effect on our perception of facial traits. This research addresses the problem of measuring the size of these effects for five facial features (eyes, eyebrows, nose, mouth, and jaw). Our proposal is a mixed feature-based and image-based approach that allows judgments to be made on complete real faces in the categorization tasks, more than on synthetic, noisy, or partial faces that can influence the assessment. Each facial feature of the faces is automatically classified considering their global appearance using principal component analysis. Using this procedure, we establish a reduced set of relevant specific attributes (each one describing a complete facial feature) to characterize faces. In this way, a more direct link can be established between perceived facial traits and what people intuitively consider an eye, an eyebrow, a nose, a mouth, or a jaw. A set of 92 male faces were classified using this procedure, and the results were related to their scores in 15 perceived facial traits. We show that the relevant features greatly depend on what we are trying to judge. Globally, the eyes have the greatest effect. However, other facial features are more relevant for some judgments like the mouth for happiness and femininity or the nose for dominance.

A Flexible Neural Representation of Faces in the Human Brain

An important question in human face perception research is to understand whether the neural representation of faces is dynamically modulated by context. In particular, although there is a plethora of neuroimaging literature that has probed the neural representation of faces, few studies have investigated what low-level structural and textural facial features parametrically drive neural responses to faces and whether the representation of these features is modulated by the task. To answer these questions, we employed 2 task instructions when participants viewed the same faces. We first identified brain regions that parametrically encoded high-level social traits such as perceived facial trustworthiness and dominance, and we showed that these brain regions were modulated by task instructions. We then employed a data-driven computational face model with parametrically generated faces and identified brain regions that encoded low-level variation in the faces (shape and skin texture) that drove neural responses. We further analyzed the evolution of the neural feature vectors along the visual processing stream and visualized and explained these feature vectors. Together, our results showed a flexible neural representation of faces for both low-level features and high-level social traits in the human brain.

Social motivation is associated with increased weight granted to cooperation-related impressions in face evaluation tasks

It is a trope in psychological science to define the human species as inherently social. Yet, despite its key role in human behaviour, the mechanisms by which social bonding actually shapes social behaviour have not been fully characterized. Across six studies, we show that the motivation for social bonding does not indiscriminately increase individuals’ willingness to approach others but that it is instead associated with specific variations in social evaluations. Studies 1–4 demonstrate that social motivation is associated with a larger importance granted to cooperation-related impressions, i.e. perceived trustworthiness, during social evaluations. Studies 5 and 6 further reveal that this weighting difference leads strongly socially motivated participants to approach more partners that are perceived as both dominant and trustworthy. Taken together, our results provide support for the idea that humans’ social motivation is associated with specific social preferences that could favour successful cooperative interactions and a widening of people’s cooperative circle.

Evidence Head Tilt Has Dissociable Effects on Dominance and Trustworthiness Judgments, But Does Not Have Category-Contingent Effects on Hypothetical Leadership Judgments

Previous research has found that physical characteristics in faces that influence perceptions of trustworthiness and dominance have context-contingent effects on leadership perceptions. People whose faces are perceived to be trustworthy are judged to be better leaders in peacetime contexts than wartime contexts. By contrast, people whose faces are perceived to be dominant are judged to be better leaders in wartime contexts than peacetime contexts. Here, we tested for judgment-contingent (dominance vs. trustworthiness) effects of head tilt (i.e., head pitch rotation) on person perception and context-contingent (peacetime vs. wartime) effects of head tilt on leadership judgments. Although we found that head tilt influenced judgments of trustworthiness and dominance (Study 1), head tilt did not influence leadership judgments (Study 2). Together, these results suggest that the context-contingent effects of physical characteristics on leadership judgments reported in previous work do not necessarily extend to head tilt, even though head tilt influences perceptions of trustworthiness and dominance.

Social Transmission of Leadership Preference: Knowledge of Group Membership and Partisan Media Reporting Moderates Perceptions of Leadership Ability From Facial Cues to Competence and Dominance

While first impressions of dominance and competence can influence leadership preference, social transmission of leadership preference has received little attention. The capacity to transmit, store and compute information has increased greatly over recent history, and the new media environment may encourage partisanship (i.e., "echo chambers"), misinformation and rumor spreading to support political and social causes and be conducive both to emotive writing and emotional contagion, which may shape voting behavior. In our pre-registered experiment, we examined whether implicit associations between facial cues to dominance and competence (intelligence) and leadership ability are strengthened by partisan media and knowledge that leaders support or oppose us on a socio-political issue of personal importance. Social information, in general, reduced well-established implicit associations between facial cues and leadership ability. However, as predicted, social knowledge of group membership reduced preferences for facial cues to high dominance and intelligence in out-group leaders. In the opposite-direction to our original prediction, this "in-group bias" was greater under less partisan versus partisan media, with partisan writing eliciting greater state anxiety across the sample. Partisanship also altered the salience of women's facial appearance (i.e., cues to high dominance and intelligence) in out-group versus in-group leaders. Independent of the media environment, men and women displayed an in-group bias toward facial cues of dominance in same-sex leaders. Our findings reveal effects of minimal social information (facial appearance, group membership, media reporting) on leadership judgments, which may have implications for patterns of voting or socio-political behavior at the local or national level.

The Role of Face and Voice Cues in Predicting the Outcome of Student Representative Elections

First impressions formed after seeing someone's face or hearing their voice can affect many social decisions, including voting in political elections. Despite the many studies investigating the independent contribution of face and voice cues to electoral success, their integration is still not well understood. Here, we examine a novel electoral context, student representative ballots, allowing us to test the generalizability of previous studies. We also examine the independent contributions of visual, auditory, and audiovisual information to social judgments of the candidates, and their relationship to election outcomes. Results showed that perceived trustworthiness was the only trait significantly related to election success. These findings contrast with previous reports on the importance of perceived competence using audio or visual cues only in the context of national political elections. The present study highlights the role of real-world context and emphasizes the importance of using ecologically valid stimulus presentation in understanding real-life social judgment.

A robust implicit measure of facial attractiveness discrimination

Decisions of attractiveness from the human face are made instantly and spontaneously, but robust implicit neural measures of facial attractiveness discrimination are currently lacking. Here we applied fast periodic visual stimulation coupled with electroencephalography (EEG) to objectively measure the neural coding of facial attractiveness. We presented different pictures of faces at 6 Hz, i.e. six faces/second, for a minute while participants attended to a central fixation cross and indicated whether the cross shortly changed color. Every other face in the stimulation was attractive and was replaced by a relatively less attractive face. This resulted in alternating more/less attractive faces at a 3 Hz rate, eliciting a significant increase in occipito-temporal EEG amplitude at 3 Hz both at the group and the individual participant level. This response was absent in two control conditions where either only attractive or only less attractive faces were presented. These observations support the view that face-sensitive visual areas discriminate attractiveness implicitly and rapidly from the human face.

Context-specific effects of facial dominance and trustworthiness on hypothetical leadership decisions

Social judgments of faces predict important social outcomes, including leadership decisions. Previous work suggests that facial cues associated with perceptions of dominance and trustworthiness have context-specific effects on leadership decisions. Facial cues linked to perceived dominance have been found to be preferred in leaders for hypothetical wartime contexts and facial cues linked to perceived trustworthiness have been found to be preferred in leaders for hypothetical peacetime contexts. Here we sought to replicate these effects using images of women’s faces, as previous studies have primarily focused on perceptions of leadership abilities from male faces, with only a handful of these including female faces. Consistent with previous work, a linear mixed effects model demonstrated that more trustworthy-looking faces were preferred in leaders during times of peace and more dominant-looking faces were preferred in leaders during times of war. These results provide converging evidence for context-specific effects of facial cues on hypothetical leadership judgments.

Dominant leaders and the political psychology of followership

What is the psychology underlying preferences for dominant political leaders? Against earlier theories about authoritarianism and submissiveness, recent research shows that followers strategically promote dominant individuals to leadership positions in order to enhance their ability to aggress against other groups. Thus, recent evidence supports the existence of dedicated mechanisms for generating summary impressions of the dominance of potential leaders from a wealth of cues. Furthermore, research demonstrates how preferences for dominant leaders are heightened in contexts of conflict and among individuals prone to view the social world as conflictual. At the same time, this research shows that followers intuitively fear exploitation from dominant leaders and the political psychology of followership also contains dedicated mechanisms for identifying and counteracting such exploitation.

Honest Signals of Status: Facial and Bodily Dominance Are Related to Success in Physical but Not Nonphysical Competition

Recent studies suggest that both facial and bodily dominance promote high status positions and predict status-seeking behaviors such as aggression and social dominance. An evolutionarily relevant context in which associations between these dominance signals and status outcomes may be prevalent are face-to-face status contests. The present study examined whether facial and bodily dominance predicted success in dyadic competitions (one physical discipline, arm wrestling, and three nonphysical disciplines) in men (N = 125) in a controlled laboratory setting. Men's bodies and faces were independently rated for physical dominance, and associations of these ratings with contest outcomes as well as mediating and moderating variables (such as physical strength, body height, trait dominance, baseline and reactive testosterone) were examined. Both facial and bodily dominance positively predicted success in the physical discipline, mediated by physical strength, but not in the three nonphysical disciplines. Our findings demonstrate that facial and bodily physical dominance may be honest signals for men's formidability and hence status potential, at least in a physically competitive context.