Clare A. M. Sutherland

Modeling first impressions from highly variable facial images.

Significance Understanding how first impressions are formed to faces is a topic of major theoretical and practical interest that has been given added importance through the widespread use of images of faces in social media. We create a quantitative model that can predict first impressions of previously unseen ambient images of faces (photographs reflecting the variability encountered in everyday life) from a linear combination of facial attributes, explaining 58% of the variance in raters’ impressions despite the considerable variability of the photographs. Reversing this process, we then demonstrate that face-like images can be generated that yield predictable social trait impressions in naive raters because they capture key aspects of the systematic variation in the relevant physical features of real faces. 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.

Facial first impressions from another angle: How social judgements are influenced by changeable and invariant facial properties

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.

Face gender and stereotypicality influence facial trait evaluation: counter-stereotypical female faces are negatively evaluated

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.

Facial Stereotype Visualization Through Image Averaging

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.

Hearing brighter: Changing in-depth visual perception through looming sounds

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.

The unique contributions of perceiver and target characteristics in person perception.

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.

Integrating social and facial models of person perception: Converging and diverging 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 strangers capability to help or harm.

Facial image manipulation: A tool for investigating social perception

Image manipulation of real face photographs, including averaging, morphing, and caricaturing, is widely used in studies of face perception. These methods have led to theoretical insights across topics of interest to social psychologists, including social perception, social categorization, stereotyping, prejudice, impression formation, and individual differences. They may also have practical applications in diagnosing clinical impairments of social perception. Here, we outline key manipulation methods, comment on the strengths and weaknesses of the approach, illustrate the breadth of theoretical insights already achieved, and offer best practice guidelines. We hope that the review stimulates greater use of these powerful methods to understand social perception and encourages studies that bridge theory between visual perception and social psychology.

The neuropsychology of first impressions: Evidence from Huntington's disease

Impairments of emotion recognition have been widely documented in Huntingtons 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.

Facial first impressions across culture: data-driven modelling of Chinese and British perceivers’ unconstrained facial impressions

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.