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Although it is often assumed that humans spontaneously respond to the trustworthiness of others' faces, it is still unclear whether responses to facial trust are mandatory or can be modulated by instructions. Considerable scientific interest lies in understanding whether trust processing is mandatory, given the societal consequences of biased trusting behavior. We tested whether neural responses indexing trustworthiness discrimination depended on whether the task involved focusing on facial trustworthiness or not, using a fast periodic visual stimulation electroencephalography oddball paradigm with a neural marker of trustworthiness discrimination at 1 Hz. Participants judged faces on size without any reference to trust, explicitly formed impressions of facial trust, or were given a financial lending context that primed trust, without explicit trust judgement instructions. Significant trustworthiness discrimination responses at 1 Hz were found in all three conditions, demonstrating the robust nature of trustworthiness discrimination at the neural level. Moreover, no effect of task instruction was observed, with Bayesian analyses providing moderate to decisive evidence that task instruction did not affect trustworthiness discrimination. Our finding that visual trustworthiness discrimination is mandatory points to the remarkable spontaneity of trustworthiness processing, providing clues regarding why these often unreliable impressions are ubiquitous.

People draw automatic social inferences from photos of unfamiliar faces and these first impressions are associated with important real-world outcomes. Here we examine the effect of selecting online profile images on first impressions. We model the process of profile image selection by asking participants to indicate the likelihood that images of their own face ("self-selection") and of an unfamiliar face ("other-selection") would be used as profile images on key social networking sites. Across two large Internet-based studies (n = 610), in line with predictions, image selections accentuated favorable social impressions and these impressions were aligned to the social context of the networking sites. However, contrary to predictions based on people's general expertise in self-presentation, other-selected images conferred more favorable impressions than self-selected images. We conclude that people make suboptimal choices when selecting their own profile pictures, such that self-perception places important limits on facial first impressions formed by others. These results underscore the dynamic nature of person perception in real-world contexts.

Significance Rapid impressions of trustworthiness can have extreme consequences, impacting financial lending, partner selection, and death-penalty sentencing decisions. But to what extent do people disagree about who looks trustworthy, and why? Here, we demonstrate that individual differences in trustworthiness and other impressions are substantial and stable, agreeing with the classic idea that social perception can be influenced in part by the “eye of the beholder.” Moreover, by examining twins, we show that individual differences in impressions of trustworthiness are shaped mostly by personal experiences, instead of genes or familial experiences. Our study highlights individual social learning as a key mechanism by which we individually come to trust others, with potentially profound consequences for everyday trust decisions., People evaluate a stranger’s trustworthiness from their facial features in a fraction of a second, despite common advice “not to judge a book by its cover.” Evaluations of trustworthiness have critical and widespread social impact, predicting financial lending, mate selection, and even criminal justice outcomes. Consequently, understanding how people perceive trustworthiness from faces has been a major focus of scientific inquiry, and detailed models explain how consensus impressions of trustworthiness are driven by facial attributes. However, facial impression models do not consider variation between observers. Here, we develop a sensitive test of trustworthiness evaluation and use it to document substantial, stable individual differences in trustworthiness impressions. Via a twin study, we show that these individual differences are largely shaped by variation in personal experience, rather than genes or shared environments. Finally, using multivariate twin modeling, we show that variation in trustworthiness evaluation is specific, dissociating from other key facial evaluations of dominance and attractiveness. Our finding that variation in facial trustworthiness evaluation is driven mostly by personal experience represents a rare example of a core social perceptual capacity being predominantly shaped by a person’s unique environment. Notably, it stands in sharp contrast to variation in facial recognition ability, which is driven mostly by genes. Our study provides insights into the development of the social brain, offers a different perspective on disagreement in trust in wider society, and motivates new research into the origins and potential malleability of face evaluation, a critical aspect of human social cognition.

Adults teach children not to "judge a book by its cover." However, adults make rapid judgments of character from a glance at a child's face. These impressions can be modestly accurate, suggesting that adults may be sensitive to valid signals of character in children's faces. However, it is not clear whether such sensitivity requires decades of social experience, in line with the development of other face-processing abilities (e.g., facial emotion recognition), or whether this sensitivity emerges relatively early, in childhood. An important theoretical question therefore, is whether or not children's impressions are at all accurate. Here, we examined the accuracy in children's impressions of niceness and shyness from children's faces. Children (aged 7-12 years, ∼90% Caucasian) and adults rated 84 unfamiliar children's faces (aged 4-11 years, 48 female, ∼80% Caucasian) for niceness (Study 1) or shyness (Study 2). To measure accuracy, we correlated facial impressions with parental responses to well-established questionnaires about the actual niceness/shyness of those children in the images. Overall, children and adults formed highly similar niceness (r = .94) and shyness (r = .84) impressions. Children also showed mature impression accuracy: Children and adults formed modestly accurate niceness impressions, across different images of the same child's face. Neither children nor adults showed evidence for accurate shyness impressions. Together, these results suggest that children's impressions are relatively mature by middle childhood. Furthermore, these results demonstrate that any mechanisms driving accurate niceness impressions are in place by 7 years, and potentially before. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Correction to: Nature Human Behaviour https://doi.org/10.1038/s41562-021-01173-x, published online 2 August 2021.In the version of this article initially published, the following authors were omitted from the author list and the Author contributionssection for “investigation” and “writing and editing”: Nandor Hajdu (Institute of Psychology, ELTE Eötvös Loránd University, Budapest,Hungary), Jordane Boudesseul (Facultad de Psicología, Instituto de Investigación Científica, Universidad de Lima, Lima, Perú), RafałMuda (Faculty of Economics, Maria Curie-Sklodowska University, Lublin, Poland) and Sandersan Onie (Black Dog Institute, UNSWSydney, Sydney, Australia & Emotional Health for All Foundation, Jakarta, Indonesia). In addition, Saeideh FatahModares’ name wasoriginally misspelled as Saiedeh FatahModarres in the author list. Further, affiliations have been corrected for Maria Terskova (NationalResearch University Higher School of Economics, Moscow, Russia), Susana Ruiz Fernandez (FOM University of Applied Sciences,Essen; Leibniz-Institut fur Wissensmedien, Tubingen, and LEAD Research Network, Eberhard Karls University, Tubingen, Germany),Hendrik Godbersen (FOM University of Applied Sciences, Essen, Germany), Gulnaz Anjum (Department of Psychology, Simon FraserUniversity, Burnaby, Canada, and Department of Economics & Social Sciences, Institute of Business Administration, Karachi, Pakistan).

Despite warnings not to “judge a book by its cover,” people rapidly form facial impressions. In Oosterhof and Todorov’s (2008) two-dimensional model of facial impressions, trustworthiness, and dominance underlie impressions and primarily function to signal the potential threat of others. Here, we test a key assumption of these models, namely that these dimensions are functional, by evaluating whether the adult-face dimensions apply to young children’s faces. Although it may be functional for adults to judge adult faces on dimensions that signal threat, adults associate different social goals with children, and these goals are likely to impact the impressions adults make of such faces. Thus, a functional approach would predict that the dimensions for children’s faces are not threat focused. In Studies 1 and 2, we build a data-driven model of Caucasian adults’ impressions of Caucasian children’s faces, finding evidence for two dimensions. The first dimension, niceness, is similar (although not identical) to the adult dimension of trustworthiness. However, we find a second dimension, shyness, that is clearly dissociable from dominance (Study 3), and critically, is not focused on threat. We demonstrate that adults are sensitive to subtle facial manipulations of these dimensions (Studies 4 and 5) and that these impressions impact adults’ behavioral expectations of children (Study 6). Finally, we show that niceness and shyness dimensions generalize to an independent sample of ambient images, demonstrating their robustness (Study 7). Our results suggest that social goals have the power to drive functional impressions and highlight the flexibility of our visual system when forming such inferences. (PsycINFO Database Record (c) 2019 APA, all rights reserved)

Objectives: Schizophrenia is characterized by impaired social interactions and altered trust. In the general population, trust is often based on facial appearance, with limited validity but enormous social consequences. The aim was to examine trust processing in schizophrenia and specifically to examine how people with schizophrenia use facial appearance as well as actual partner fairness to guide trusting decisions. Design: An experimental economic game study. Methods: Here, we tested how patients with schizophrenia and control participants (each N = 24) use facial trustworthiness appearance and partner fairness behaviour to guide decisions in a multi-round Trust Game. In the Trust Game, participants lent money to ‘partners’ whose facial appearance was either untrustworthy or trustworthy, and who either played fairly or unfairly. Clinical symptoms were measured as well as explicit trustworthiness impressions. Results: Overall, the patients with schizophrenia showed unimpaired explicit facial trustworthiness impressions and unimpaired facial appearance biases in the Trust Game. Crucially, patients and controls significantly differed so that the patients with schizophrenia did not learn to discriminate in the Trust Game based on actual partner fairness, unlike control participants. Conclusion: A failure to discriminate trust has important implications for everyday functioning in schizophrenia, as forming accurate trustworthiness beliefs is an essential social skill. Critically, without relying on more valid trust cues, people with schizophrenia may be especially susceptible to the misleading effect of appearance when making trusting decisions. Practitioner points: Findings. People with schizophrenia made very similar facial trustworthiness impressions to healthy controls and also used facial appearance to guide trust decisions similarly to controls. However, the patient group were less able to explicitly distinguish between fair and unfair partners based on their behaviour compared with the control group. Moreover, people with schizophrenia failed to use actual partner fairness to guide their financial decisions in the Trust Game, unlike controls, and this impairment was specific to a social task. People with schizophrenia may be particularly reliant on facial appearance when trusting others, as they may struggle to incorporate more valid trustworthiness information in their decision-making, such as actual partner fairness.

Lay wisdom warns against “judging a book by its cover.” However, facial first impressions influence people’s behaviour towards others, so it is critical that we understand whether these impressions are at all accurate. Understanding impressions of children’s faces is particularly important because these impressions can have social consequences during a crucial time of development. Here, we examined the accuracy of two traits that capture the most variance in impressions of children’s faces, niceness and shyness. We collected face images and parental reports of actual niceness/shyness for 86 children (4–11 years old). Different images of the same person can lead to different impressions, and so we employed a novel approach by obtaining impressions from five images of each child. These images were ambient, representing the natural variability in faces. Adult strangers rated the faces for niceness (Study 1) or shyness (Study 2). Niceness impressions were modestly accurate for different images of the same child, regardless of whether these images were presented individually or simultaneously as a group. Shyness impressions were not accurate, for images presented either individually or as a group. Together, these results demonstrate modest accuracy in adults’ impressions of niceness, but not shyness, from children’s faces. Furthermore, our results reveal that this accuracy can be captured by images which contain natural face variability, and holds across different images of the same child’s face. These results invite future research into the cues and causal mechanisms underlying this link between facial impressions of niceness and nice behaviour in children.

Trustworthiness is assumed to be processed implicitly from faces, despite the fact that the overwhelming majority of research has only involved explicit trustworthiness judgements. To answer the question whether or not trustworthiness processing can be implicit, we apply an electroencephalography fast periodic visual stimulation (FPVS) paradigm, where electrophysiological cortical activity is triggered in synchrony with facial trustworthiness cues, without explicit judgements. Face images were presented at 6 Hz, with facial trustworthiness varying at 1 Hz. Significant responses at 1 Hz were observed, indicating that differences in the trustworthiness of the faces were reflected in the neural signature. These responses were significantly reduced for inverted faces, suggesting that the results are associated with higher order face processing. The neural responses were reliable, and correlated with explicit trustworthiness judgements, suggesting that the technique is capable of picking up on stable individual differences in trustworthiness processing. By demonstrating neural activity associated with implicit trustworthiness judgements, our results contribute to resolving a key theoretical debate. Moreover, our data show that FPVS is a valuable tool to examine face processing at the individual level, with potential application in pre-verbal and clinical populations who struggle with verbalization, understanding or memory.

People form first impressions from facial appearance rapidly, and these impressions can have considerable social and economic consequences. Three dimensions can explain Western perceivers’ impressions of Caucasian faces: approachability, youthful-attractiveness, and dominance. Impressions along these dimensions are theorized to be based on adaptive cues to threat detection or sexual selection, making it likely that they are universal. We tested whether the same dimensions of facial impressions emerge across culture by building data-driven models of first impressions of Asian and Caucasian faces derived from Chinese and British perceivers’ unconstrained judgments. We then cross-validated the dimensions with computer-generated average images. We found strong evidence for common approachability and youthful-attractiveness dimensions across perceiver and face race, with some evidence of a third dimension akin to capability. The models explained ~75% of the variance in facial impressions. In general, the findings demonstrate substantial cross-cultural agreement in facial impressions, especially on the most salient dimensions.

Models of first impressions from faces have consistently found two underlying dimensions of trustworthiness and dominance. These dimensions show apparent parallels to social psychological models of inter-group perception that describe dimensions of warmth (cf. trustworthiness) and competence (cf. dominance), and it has been suggested that they reflect universal dimensions of social cognition. We investigated whether the dimensions from face and inter-group social perception models are indeed equivalent by evaluating first impressions of faces. Across four studies with differing methods we consistently found that while perceptions of trustworthiness and warmth were closely related, perceptions of dominance and competence were less strongly related. Taken together, our results demonstrate strong similarity on the first dimension across facial and social models, with less similarity on the second dimension. We suggest that facial impressions of competence and dominance may represent different routes to judging a stranger's capability to help or harm.

We routinely make judgements of trustworthiness from the faces of others. However, the accuracy of such judgements remains contentious. An important context for trustworthiness judgements is sexual unfaithfulness. Accuracy in sexual unfaithfulness judgements may be adaptive for avoiding reproductive costs associated with having an unfaithful partner. Indeed, emerging studies suggest that women, and to a lesser degree, men, show above-chance accuracy in judging sexual unfaithfulness from opposite-sex faces. In the context of mate guarding, it is important not only to assess the likelihood of a partner defecting, but also to detect same-sex poachers. Therefore, here, we examine whether individuals can also judge sexual unfaithfulness (self-reported cheating and poaching behaviour) from same-sex faces. We found above-chance accuracy in judgements of unfaithfulness from same-sex faces in men but not women. Conversely, we found above-chance accuracy for opposite-sex faces in women but not men. Therefore, both men and women showed above-chance accuracy, but only for men's, and not women's, faces. Raters were making accurate (above-chance) judgements of unfaithfulness from men's faces using facial masculinity, a well-established signal of propensity to adopt short-term mating strategies. In summary, we found above-chance accuracy in impressions of unfaithfulness from men's faces. Although very modest, the level of accuracy could nevertheless have biological significance as an evolved adaptation for identifying potential cheaters/poachers.

A common goal in psychological research is the measurement of subjective impressions, such as first impressions of faces. These impressions are commonly measured using Likert ratings. Although these ratings are simple to administer, they are associated with response issues that can limit reliability. Here we examine best-worst scaling (BWS), a forced-choice method, as a potential alternative to Likert ratings for measuring participants’ facial first impressions. We find that at the group level, BWS scores correlated almost perfectly with Likert scores, indicating that the two methods measure the same impressions. However, at the individual participant level BWS outperforms Likert ratings, both in terms of ability to predict preferences in a third task, and in terms of test-retest reliability. These benefits highlight the power of BWS, particularly for use in individual differences research. Electronic supplementary material The online version of this article (10.1186/s41235-019-0183-2) contains supplementary material, which is available to authorized users.

Influential facial impression models have repeatedly shown that trustworthiness, youthful-attractiveness, and dominance dimensions subserve a wide variety of first impressions formed from strangers' faces, suggestive of a shared social reality. However, these models are built from impressions aggregated across observers. Critically, recent work has now shown substantial inter-observer differences in facial impressions, raising the important question of whether these dimensional models based on aggregated group data are meaningful at the individual observer level. We addressed this question with a novel case series approach, using factor analyses of ratings of twelve different traits to build individual models of facial impressions for different observers. Strikingly, three dimensions of trustworthiness, youthful/attractiveness, and competence/dominance appeared across the majority of these individual observer models, demonstrating that the dimensional approach is indeed meaningful at the individual level. Nonetheless, we also found differences in the stability of the competence/dominance dimension across observers. Taken together, results suggest that individual differences in impressions arise in the context of a largely common structure that supports a shared social reality.

Facial impressions of trustworthiness guide social decisions in the general population, as shown by financial lending in economic Trust Games. As an exception, autistic boys fail to use facial impressions to guide trust decisions, despite forming typical facial trustworthiness impressions (Autism, 19, 2015a, 1002). Here, we tested whether this dissociation between forming and using facial impressions of trustworthiness extends to neurotypical men with high levels of autistic traits. Forty-six Caucasian men completed a multi-turn Trust Game, a facial trustworthiness impressions task, the Autism-Spectrum Quotient, and two Theory of Mind tasks. As hypothesized, participants' levels of autistic traits had no observed effect on the impressions formed, but negatively predicted the use of those impressions in trust decisions. Thus, the dissociation between forming and using facial impressions of trustworthiness extends to the broader autism phenotype. More broadly, our results identify autistic traits as an important source of individual variation in the use of facial impressions to guide behaviour. Interestingly, failure to use these impressions could potentially represent rational behaviour, given their limited validity.

Given the frequency of relationships nowadays initiated online, where impressions from face photographs may influence relationship initiation, it is important to understand how facial first impressions might be used in such contexts. We therefore examined the applicability of a leading model of verbally expressed partner preferences to impressions derived from real face images and investigated how the factor structure of first impressions based on potential partner preference-related traits might relate to a more general model of facial first impressions. Participants rated 1,000 everyday face photographs on 12 traits selected to represent (Fletcher, et al. 1999, Journal of Personality and Social Psychology, 76, 72) verbal model of partner preferences. Facial trait judgements showed an underlying structure that largely paralleled the tripartite structure of Fletcher et al.'s verbal preference model, regardless of either face gender or participant gender. Furthermore, there was close correspondence between the verbal partner preference model and a more general tripartite model of facial first impressions derived from a different literature (Sutherland et al., 2013, Cognition, 127, 105), suggesting an underlying correspondence between verbal conceptual models of romantic preferences and more general models of facial first impressions.

Objective It is not clear how well evaluations made by other people correspond with self-evaluations of esteem or confidence. To address this question, we compared measurements of confidence in participants with and without dandruff. Methods Participants with dandruff were significantly different from healthy control participants on a quality of life measure of scalp dermatitis, but not on self-evaluations of esteem or confidence. To determine whether there were differences in the evaluation of confidence by others, both groups of participants were videoed while they prepared for or gave a presentation in an interview scenario. Results Raters, who were unfamiliar with the identities of the participants, evaluated confidence from the muted videos. In contrast to their self-evaluations, male participants with dandruff were rated as having lower confidence compared to participants who reported a healthy scalp. Conclusions These findings reveal a difference between explicit and implicit measures of self-esteem in men compared to women with dandruff.

Models of person perception have long asserted that our impressions of others are guided by characteristics of both the target and perceiver. However, research has not yet quantified to what extent perceivers and targets contribute to different impressions. This quantification is theoretically critical, as it addresses how much an impression arises from "our minds" versus "others' faces." Here, we apply cross-classified random effects models to address this fundamental question in social cognition, using approximately 700,000 ratings of faces. With this approach, we demonstrate that (a) different trait impressions have unique causal processes, meaning that some impressions are largely informed by perceiver-level characteristics whereas others are driven more by physical target-level characteristics; (b) modeling of perceiver- and target-variance in impressions informs fundamental models of social perception; (c) Perceiver × Target interactions explain a substantial portion of variance in impressions; (d) greater emotional intensity in stimuli decreases the influence of the perceiver; and (e) more variable, naturalistic stimuli increases variation across perceivers. Important overarching patterns emerged. Broadly, traits and dimensions representing inferences of character (e.g., dominance) are driven more by perceiver characteristics than those representing appearance-based appraisals (e.g., youthful-attractiveness). Moreover, inferences made of more ambiguous traits (e.g., creative) or displays (e.g., faces with less extreme emotions, less-controlled stimuli) are similarly driven more by perceiver than target characteristics. Together, results highlight the large role that perceiver and target variability play in trait impressions, and develop a new topography of trait impressions that considers the source of the impression. (PsycINFO Database Record

People draw automatic social inferences from photos of unfamiliar faces and these first impressions are associated with important real-world outcomes. Here we examine the effect of selecting online profile images on first impressions. We model the process of profile image selection by asking participants to indicate the likelihood that images of their own face (“self-selection”) and of an unfamiliar face (“other-selection”) would be used as profile images on key social networking sites. Across two large Internet-based studies (n = 610), in line with predictions, image selections accentuated favorable social impressions and these impressions were aligned to the social context of the networking sites. However, contrary to predictions based on people’s general expertise in self-presentation, other-selected images conferred more favorable impressions than self-selected images. We conclude that people make suboptimal choices when selecting their own profile pictures, such that self-perception places important limits on facial first impressions formed by others. These results underscore the dynamic nature of person perception in real-world contexts. Electronic supplementary material The online version of this article (doi:10.1186/s41235-017-0058-3) contains supplementary material, which is available to authorized users.

The facial first impressions literature has focused on trait dimensions, with less research on how social categories (like gender) may influence first impressions of faces. Yet, social psychological studies have shown the importance of categories like gender in the evaluation of behaviour. We investigated whether face gender affects the positive or negative evaluation of faces in terms of first impressions. In 'STUDY 1', we manipulated facial gender stereotypicality, and in 'STUDY 2', facial trustworthiness or dominance, and examined the valence of resulting spontaneous descriptions of male and female faces. For both male and female participants, counter-stereotypical (masculine or dominant looking), female faces were perceived more negatively than facially stereotypical male or female faces. In 'STUDY 3', we examined how facial dominance and trustworthiness affected rated valence across 1,000 male and female ambient face images, and replicated the finding that dominance is more negatively evaluated for female faces. In 'STUDY 4', the same effect was found with short stimulus presentations. These findings integrate the facial first impressions literature with evaluative differences based on social categories.

Three experiments are presented that investigate the two-dimensional valence/trustworthiness by dominance model of social inferences from faces (Oosterhof & Todorov, 2008). Experiment 1 used image averaging and morphing techniques to demonstrate that consistent facial cues subserve a range of social inferences, even in a highly variable sample of 1000 ambient images (images that are intended to be representative of those encountered in everyday life, see Jenkins, White, Van Montfort, & Burton, 2011). Experiment 2 then tested Oosterhof and Todorov’s two-dimensional model on this extensive sample of face images. The original two dimensions were replicated and a novel ‘youthful-attractiveness’ factor also emerged. Experiment 3 successfully cross-validated the three-dimensional model using face averages directly constructed from the factor scores. These findings highlight the utility of the original trustworthiness and dominance dimensions, but also underscore the need to utilise varied face stimuli: with a more realistically diverse set of face images, social inferences from faces show a more elaborate underlying structure than hitherto suggested.

Facial stereotypes are cognitive representations of the facial characteristics of members of social groups. In this study, we examined the extent to which facial stereotypes for occupational groups were based on physiognomic cues to stereotypical social characteristics. In Experiment 1, participants rated the occupational stereotypicality of naturalistic face images. These ratings were then regressed onto independent ratings of the faces on 16 separate traits. These traits, particularly those relevant to the occupational stereotype, explained the majority of variance in occupational stereotypicality ratings. In Experiments 2 and 3, we used trait ratings to reconstruct stereotypical occupation faces from a separate set of images, using face averaging techniques. These reconstructed facial stereotypes were validated by separate groups of participants as conforming to the occupational stereotype. These results indicate that facial cues and group stereotypes are integrated through shared semantic content in the cognitive representations of groups.

Impairments of emotion recognition have been widely documented in Huntington's disease (HD), but little is known concerning how these relate to other aspects of social cognition, including first impressions of traits such as trustworthiness and dominance. Here, we introduce a novel and sensitive method to investigate the ability to evaluate trustworthiness and dominance from facial appearance, with control tasks measuring ability to perceive differences between comparable stimuli. We used this new method together with standard tests of face perception to investigate social cognition in HD. We found that a subgroup of people with HD was impaired at perceiving trustworthiness and dominance, and that perceiving trustworthiness and dominance were correlated with impaired facial expression recognition. In addition, we used diffusion tensor imaging (DTI) to provisionally identify candidate brain regions associated with social cognition by contrasting regional functional anisotropy (FA) measures between subgroups of HD participants showing normal or impaired perception of trustworthiness and dominance, and by correlating these regional brain abnormalities with behavioural performance on tests of emotion recognition. In this way we show for the first time alterations in perception of trustworthiness and dominance in people with HD and link these to regions which may map the boundaries of the social brain. The pattern of breakdown seen in this neurodegenerative disease can thus be used to explore potential inter-relationships between different components of social cognition. Postprint

First impressions made to photographs of faces can depend as much on momentary characteristics of the photographed image (within-person variability) as on consistent properties of the face of the person depicted (between-person variability). Here, we examine two important sources of within-person variability: emotional expression and viewpoint. We find more within-person variability than between-person variability for social impressions of key traits of trustworthiness, dominance, and attractiveness, which index the main dimensions in theoretical models of facial impressions. The most important source of this variability is the emotional expression of the face, but the viewpoint of the photograph also affects impressions and modulates the effects of expression. For example, faces look most trustworthy with a happy expression when they are facing the perceiver, compared to when they are facing elsewhere, whereas the opposite is true for anger and disgust. Our findings highlight the integration of these different sources of variability in social impression formation.

Forming accurate impressions of others' trustworthiness is a critical social skill, with faithfulness representing a key aspect of trust in sexual relationships. Interestingly, there is evidence for a small degree of accuracy in facial impressions of sexual unfaithfulness. Theoretical accounts suggest that these impressions may function to help with partner selection, and may be universal. If so, impressions should be similar for perceivers from different cultures and accuracy should not be limited to own-race faces. We tested these predictions by asking Caucasian and Asian women to judge the likelihood of unfaithfulness from the faces of Caucasian males whose past sexual history was known. In two studies we found high cross-cultural agreement in these impressions, consistent with universality in the impressions themselves. In Study 1, we found an other-race effect in impression accuracy, with significantly less accurate cross-race impressions by Asian women than own-race impressions by Caucasian women. Asian women showed no accuracy. Interestingly, in Study 2, Asian women who had grown up in the West showed small but significant accuracy in their impressions, with no other-race effect. Results are consistent with a degree of universality in the accuracy of this important aspect of social perception, provided that perceivers have experience with the faces being assessed.

People readily make personality attributions to images of strangers' faces. Here we investigated the basis of these personality attributions as made to everyday, naturalistic face images. In a first study, we used 1000 highly varying “ambient image” face photographs to test the correspondence between personality judgments of the Big Five and dimensions known to underlie a range of facial first impressions: approachability, dominance, and youthful-attractiveness. Interestingly, the facial Big Five judgments were found to separate to some extent: judgments of openness, extraversion, emotional stability, and agreeableness were mainly linked to facial first impressions of approachability, whereas conscientiousness judgments involved a combination of approachability and dominance. In a second study we used average face images to investigate which main cues are used by perceivers to make impressions of the Big Five, by extracting consistent cues to impressions from the large variation in the original images. When forming impressions of strangers from highly varying, naturalistic face photographs, perceivers mainly seem to rely on broad facial cues to approachability, such as smiling.

First impressions of social traits, such as trustworthiness or dominance, are reliably perceived in faces, and despite their questionable validity they can have considerable real-world consequences. We sought to uncover the information driving such judgments, using an attribute-based approach. Attributes (physical facial features) were objectively measured from feature positions and colors in a database of highly variable "ambient" face photographs, and then used as input for a neural network to model factor dimensions (approachability, youthful-attractiveness, and dominance) thought to underlie social attributions. A linear model based on this approach was able to account for 58% of the variance in raters' impressions of previously unseen faces, and factor-attribute correlations could be used to rank attributes by their importance to each factor. Reversing this process, neural networks were then used to predict facial attributes and corresponding image properties from specific combinations of factor scores. In this way, the factors driving social trait impressions could be visualized as a series of computer-generated cartoon face-like images, depicting how attributes change along each dimension. This study shows that despite enormous variation in ambient images of faces, a substantial proportion of the variance in first impressions can be accounted for through linear changes in objectively defined features.

Rapidly approaching (looming) sounds are ecologically salient stimuli that are perceived as nearer than they are due to overestimation of their loudness change and underestimation of their distance (Neuhoff, 1998; Seifritz et al., 2002). Despite evidence for crossmodal influence by looming sounds onto visual areas (Romei, Murray, Cappe, & Thut, 2009, 2013; Tyll et al., 2013), it is unknown whether such sounds bias visual percepts in similar ways. Nearer objects appear to be larger and brighter than distant objects. If looming sounds impact visual processing, then visual stimuli paired with looming sounds should be perceived as brighter and larger, even when the visual stimuli do not provide motion cues, i.e. are static. In Experiment 1 we found that static visual objects paired with looming tones (but not static or receding tones) were perceived as larger and brighter than their actual physical properties, as if they appear closer to the observer. In a second experiment, we replicate and extend the findings of Experiment 1. Crucially, we did not find evidence of such bias by looming sounds when visual processing was disrupted via masking or when catch trials were presented, ruling out simple response bias. Finally, in a third experiment we found that looming tones do not bias visual stimulus characteristics that do not carry visual depth information such as shape, providing further evidence that they specifically impact in-depth visual processing. We conclude that looming sounds impact visual perception through a mechanism transferring in-depth sound motion information onto the relevant in-depth visual dimensions (such as size and luminance but not shape) in a crossmodal remapping of information for a genuine, evolutionary advantage in stimulus detection. © 2014 Elsevier B.V.