Laterality of expression in portraiture: putting your best cheek forward

Do bodybuilders pose symmetrically? Lateral bias analysis in mandatory poses of Mr. Olympia Classic Physique athletes

Athletes in bodybuilding can pose favouring one side or the other of the body while being evaluated in the contests. While previous research assessed lateral bias of posing in a variety of situations, no investigation has been conducted in bodybuilding. We analyzed the lateral posing bias of the Top 15 athletes for the mandatory poses in Classic Physique Mr. Olympias (2016-2023). Results revealed a general bias to the right in all poses, as either moderately or strongly right-lateralized poses were most frequent. Furthermore, "Front Double Biceps" pose was the most symmetrical, while "Your Favorite Classic Pose" was the most asymmetrical one-apart from the always lateralized "Side Chest". Interestingly, lower-placed athletes (Top 15) posed significantly more often to the right in "Side Chest", as compared to the Top 5 and Top 10 competitors. These findings contrast the left bias shown in portraiture and photography literature, likely as a consequence of motor constraints and coordination for athletes to pose to the right, along with the level of emotional expressiveness a bodybuilder may wish to reveal on stage. Our data expand previous results of posing asymmetry to the sport of bodybuilding in this pioneering research into the lateral bias of posing.

Viewpoint adaptation revealed potential representational differences between 2D images and 3D objects

For convenience and experimental control, cognitive science has relied largely on images as stimuli rather than the real, tangible objects encountered in the real world. Recent evidence suggests that the cognitive processing of images may differ from real objects, especially in the processing of spatial locations and actions, thought to be mediated by the dorsal visual stream. Perceptual and semantic processing in the ventral visual stream, however, has been assumed to be largely unaffected by the realism of objects. Several studies have found that one key difference accounting for differences between real objects and images is actability; however, less research has investigated another potential difference - the three-dimensional nature of real objects as conveyed by cues like binocular disparity. To investigate the extent to which perception is affected by the realism of a stimulus, we compared viewpoint adaptation when stimuli (a face or a kettle) were 2D (flat images without binocular disparity) vs. 3D (i.e., real, tangible objects or stereoscopic images with binocular disparity). For both faces and kettles, adaptation to 3D stimuli induced stronger viewpoint aftereffects than adaptation to 2D images when the adapting orientation was rightward. A computational model suggested that the difference in aftereffects could be explained by broader viewpoint tuning for 3D compared to 2D stimuli. Overall, our finding narrowed the gap between understanding the neural processing of visual images and real-world objects by suggesting that compared to 2D images, real and simulated 3D objects evoke more broadly tuned neural representations, which may result in stronger viewpoint invariance.

Neuropsychological Evidence Underlying Counterclockwise Bias in Running: Electroencephalography and Functional Magnetic Resonance Imaging Studies of Motor Imagery

We aimed to answer the question "why do people run the track counterclockwise (CCW)?" by investigating the neurophysiological differences in clockwise (CW) versus CCW direction using motor imagery. Three experiments were conducted with healthy adults. Electroencephalography (EEG) was used to examine hemispheric asymmetries in the prefrontal, frontal, and central regions during CW and CCW running imagery (n = 40). We also evaluated event-related potential (ERP) N200 and P300 amplitudes and latencies (n = 66) and conducted another experiment using functional magnetic resonance imaging (fMRI) (n = 30). EEG data indicated greater left frontal cortical activation during CCW imagery, whereas right frontal activation was more dominant during CW imagery. The prefrontal and central asymmetries demonstrated greater left prefrontal activation during both CW and CCW imagery, with CCW rotation exhibiting higher, though statistically insignificant, asymmetry scores than CW rotation. As a result of the fMRI experiment, greater activation was found during CW than during CCW running imagery in the brain regions of the left insula, Brodmann area 18, right caudate nucleus, left dorsolateral prefrontal cortex, left superior parietal cortex, and supplementary motor area. In the ERP experiment, no significant differences were found depending on direction. These findings suggest that CCW rotation might be associated with the motivational approach system, behavioral activation, or positive affect. However, CW rotation reflects withdrawal motivation, behavioral inhibition, or negative affect. Furthermore, CW rotation is understood to be associated with neural inefficiency, increased task difficulty, or unfamiliarity.

Abstract concepts: external influences, internal constraints, and methodological issues

There is a longstanding and widely held misconception about the relative remoteness of abstract concepts from concrete experiences. This review examines the current evidence for external influences and internal constraints on the processing, representation, and use of abstract concepts, like truth, friendship, and number. We highlight the theoretical benefit of distinguishing between grounded and embodied cognition and then ask which roles do perception, action, language, and social interaction play in acquiring, representing and using abstract concepts. By reviewing several studies, we show that they are, against the accepted definition, not detached from perception and action. Focussing on magnitude-related concepts, we also discuss evidence for cultural influences on abstract knowledge and explore how internal processes such as inner speech, metacognition, and inner bodily signals (interoception) influence the acquisition and retrieval of abstract knowledge. Finally, we discuss some methodological developments. Specifically, we focus on the importance of studies that investigate the time course of conceptual processing and we argue that, because of the paramount role of sociality for abstract concepts, new methods are necessary to study concepts in interactive situations. We conclude that bodily, linguistic, and social constraints provide important theoretical limitations for our theories of conceptual knowledge.

Putting your best face forward: Posing biases in psychologists' online portraits

When posing for portraits the position you adopt influences perceptions. As the left hemiface (controlled by the emotion-dominant right hemisphere) expresses emotion more intensely, left cheek portraits communicate stronger emotion than right cheek portraits. This phenomenon influences perceptions of both emotional expressivity and professional specialisation: while left cheek portraits emphasise emotion, right cheek portraits appear more scientific. When professionals upload photographs online to promote their services, the cheek shown consequently influences perceptions. Given the importance of empathy in establishing a therapeutic alliance, theoretically psychologists would benefit from choosing left cheek portraits to enhance their perceived emotionality. The present study thus examined psychologists' posing biases in photographs uploaded to online "Find a Psychologist" resources. Images (N = 1230) of psychologists were drawn from professional "Find a Psychologist" online databases, and coded for gender, portrait type and cheek shown. Results confirmed that psychologists show a left cheek bias, irrespective of gender and across portrait types (upper body, full body). This distinguishes psychologists from doctors and surgeons: past research reports no cheek bias in photos uploaded to "Find a Doctor" websites. The current findings suggest that psychologists may intuitively select left cheek images to enhance the communication of empathy to potential clients.

The effects of sex and handedness on masturbation laterality and other lateralized motor behaviours

Masturbation is a common human behaviour. Compared to other unimanual behaviours it has unique properties, including increased sexual and emotional arousal, and privacy. Self-reported hand preference for masturbation was examined in 104 left-handed and 103 right-handed women, and 100 left-handed and 99 right-handed men. Handedness (modified Edinburgh Handedness Inventory, EHI), footedness, eyedness, and cheek kissing preferences were also measured. Seventy nine percent used their dominant hand (always/usually) for masturbation, but left-handers (71.5%) were less consistently lateralized to use their dominant hand than right-handers (86.5%). Hand preference for masturbation correlated more strongly with handedness (EHI), than with footedness, eyedness, or cheek preference. There was no difference in masturbation frequency between left- and right-handers, but men masturbated more frequently than women, and more women (75%) than men (33%) masturbated with sex aids. For kissing the preferred cheek of an emotionally close person from the viewer's perspective, left-handers showed a left-cheek preference, and right-handers a weaker right-cheek preference. The results suggest that hemispheric asymmetries in emotion do not influence hand preference for masturbation but may promote a leftward shift in cheek kissing. In all, masturbation is lateralized in a similar way to other manual motor behaviours in left-handed and right-handed men and women.

The Women Before Me: My Journey Painting Honor Wall Portraits of Women Physicians

In this article, the authors briefly review the history and status of institutional honor wall portraits at medical schools, and they highlight the implications of a lack of diversity in these portraits for current medical students and the academic medicine pipeline. The authors then describe how contemporary portrait artists have used art as a tool for advocacy. They detail the first author's empowering and intimate journey as a medical student as she identified, connected with, and painted a portrait gallery of some of her medical school's prominent alumnae of color. This unique effort highlighted the unsung accomplishments of these women physicians and served to combat the visual disparity in honor wall portraits on campus. The authors also outline the common barriers faced by the portrait subjects and the key validation they offered the first author, a fellow woman of color. The authors describe the historical and psychological significance of several artistic decisions made for these portraits in weighing the intersections of race, gender, and profession. They then emphasize the reciprocal nature of oil portraiture and how, through painting these women, the first author was able to better envision her community of mentors, deepen her commitment to diversity and inclusion, and strengthen her own career aspirations. These portraits will hang in the student center of Harvard Medical School and will serve as a lasting reminder to future trainees, especially women and people of color, that they belong in the halls of medicine.

Do you know your best side? Awareness of lateral posing asymmetries

People tend to show the left cheek to broadly express emotions while they tend to show the right cheek to hide emotions because emotions were expressed more on the left than on the right side of the face. The present study investigated the level of awareness on the left- and right-cheek poses using the method of structural knowledge attributions. When asked to broadly express emotions for a family portrait, right-handed participants were more likely to show the left cheek than the right. On the other hand, when asked to conceal emotions to show a calm and reassuring attitude as a scientist, they were more likely to show the right cheek. After the posing session, participants selected the conscious level of their knowledge about posing from five categories: Random, intuition, familiarity, recollection, and rules. Most participants rated their knowledge as unconscious (i.e., either as random, intuition, or familiarity). The choice of the conscious level did not differ across posing orientations and posing instructions. These results suggest that although people do not have an acute awareness of their lateral posing preference, they reliably show one side of their faces to express or hide emotions.

The Brain’s Asymmetric Frequency Tuning: Asymmetric Behavior Originates from Asymmetric Perception

To construct a coherent multi-modal percept, vertebrate brains extract low-level features (such as spatial and temporal frequencies) from incoming sensory signals. However, because frequency processing is lateralized with the right hemisphere favouring low frequencies while the left favours higher frequencies, this introduces asymmetries between the hemispheres. Here, we describe how this lateralization shapes the development of several cognitive domains, ranging from visuo-spatial and numerical cognition to language, social cognition, and even aesthetic appreciation, and leads to the emergence of asymmetries in behaviour. We discuss the neuropsychological and educational implications of these emergent asymmetries and suggest future research approaches.

Phylogenetic proximity influences humans' depictions of nonhuman primates on Instagram

Portraits of humans favour the left cheek, with emotion thought to drive this posing asymmetry. In primates the emotion-dominant right hemisphere predominantly controls the left hemiface, rendering the left cheek anatomically more expressive than the right. As perceptions of nonhuman primates vary with genetic relatedness, depictions of nonhuman primates should theoretically be influenced by their phylogenetic proximity to humans. The present study thus examined whether humans depict nonhuman primates showing the left cheek, and whether depictions vary with evolutionary distance. Photographs of nonhuman primates were sourced from Instagram's "Most recent" feed: great apes (#chimpanzee, #bonobo, #gorilla, #orangutan), lesser apes (#gibbon), Old World monkeys (#baboon, #macaque, #proboscismonkey), New World monkeys (#spidermonkey, #marmosetmonkey, #capuchin), and prosimians (#lemur, #slowloris, #tarsier). The first 500 single-subject images for each hashtag (except #slowloris for which 318 images were available) were coded for pose orientation (left, right) and portrait type (head/torso, full body). As anticipated, there was a left cheek bias for great apes but no bias for more distantly related primates. These data thus suggest that depictions of nonhuman primates are implicitly influenced by phylogenetic proximity: the more closely related the primate, the more likely we are to depict them as we do ourselves, showing the left cheek.

Which Side Looks Better? Cultural Differences in Preference for Left- or Right-Facing Objects

An oblique view of three-dimensional objects is preferred over a frontal or lateral view, partly because it is more familiar and easily recognizable. However, which side of a symmetric object looks better remains unsolved. Reading direction, handedness, and the functionality of objects have been suggested as the potential sources of directional bias. In this study, participants of three online surveys (total N = 1082) were asked to choose one item that looked better or was more aesthetically pleasing; the test was performed between 100 pairs of left- and right-facing mirror-images. The results showed that Japanese participants (both vertical and left-to-right readers) and Israeli participants (right-to-left readers) preferred left-facing images over right-facing images, whereas American participants (left-to-right readers) preferred right-facing images over left-facing images. Weak effects of handedness and object functionality were also found: Left-handers tended to choose right-facing images more than right-handers, and the view of objects with a handle that is graspable by the dominant hand was more likely to be chosen over the opposite side view, regardless of culture. Although previous studies have emphasized the role of reading direction, a close look at the results suggests that it cannot fully account for the preferred facing direction of oblique objects.

Instagram Advertisements Favor the Left Cheek

The growth of social media has catalyzed a shift in marketing expenditure away from traditional print media. As Instagram posts featuring left cheek poses gain more "likes" than right cheek poses, advertisers and social media influencers would likely benefit from favoring the left cheek. While previous investigations of posing biases in print advertising present a conflicting picture, research has yet to investigate posing biases in Instagram advertisements. Given that left cheek images garner more "likes" than right cheek images, we hypothesized a left cheek bias for Instagram advertisements. Two thousand posts (F = M) were sourced by searching Instagram's "Most Recent" feed using the #ad, and coded for pose orientation, image type, and model gender. As predicted, Instagram advertisements showed a left cheek bias (59.8 percent) that was evident across genders and image types, being stronger for female than male models, and for full body than head and torso poses. As such, these data indicate that the left cheek bias that characterizes painted and photographic portraits extends to paid Instagram promotions. The difference in bias from previous investigations of posing orientation in print media advertisements may reflect the importance of emotion in driving attentional capture in social media's highly competitive and content-overloaded landscape.

Turning Heads: The Effects of Face View and Eye Gaze Direction on the Perceived Attractiveness of Expressive Faces

We investigated whether the perceived attractiveness of expressive faces was influenced by head turn and eye gaze towards or away from the observer. In all experiments, happy faces were consistently rated as more attractive than angry faces. A head turn towards the observer, whereby a full-face view was shown, was associated with relatively higher attractiveness ratings when gaze direction was aligned with face view (Experiment 1). However, preference for full-face views of happy faces was not affected by gaze shifts towards or away from the observer (Experiment 2a). In Experiment 3, the relative duration of each face view (front-facing or averted at 15°) during a head turn away or towards the observer was manipulated. There was benefit on attractiveness ratings for happy faces shown for a longer duration from the front view, regardless of the direction of head turn. Our findings support previous studies indicating a preference for positive expressions on attractiveness judgements, which is further enhanced by the front views of faces, whether presented during a head turn or shown statically. In sum, our findings imply a complex interaction between cues of social attention, indicated by the view of the face shown, and reward on attractiveness judgements of unfamiliar faces.

Humans' left cheek portrait bias extends to chimpanzees: Depictions of chimps on Instagram

When posing for portraits, humans favour the left cheek. This preference is argued to stem from the left cheek's greater expressivity: as the left hemiface is predominantly controlled by the emotion-dominant right hemisphere, it expresses emotion more intensely than the right hemiface. Whether this left cheek bias extends to our closest primate relatives, chimpanzees, has yet to be determined. Given that humans and chimpanzees share the same oro-facial musculature and contralateral cortical innervation of the face, it appears probable that humans would also choose to depict chimps showing the more emotional left cheek. This paper thus examined portrait biases in images of chimpanzees. Two thousand photographs were sourced from Instagram's "Most Recent" feed using the #chimpanzee, and coded for pose orientation (left, right) and portrait type (head and torso, full body). As anticipated, there were significantly more left cheek (57.2%) than right cheek images (42.8%), with the bias observed across both head and torso and full body portraits. Thus humans choose to depict chimpanzees just as we depict ourselves: offering the left cheek. As such, these data confirm that the left cheek bias is observed in both human and non-human primates, consistent with an emotion-based account of the orientation preference.

Differences over time in head orientation in European portrait paintings

There is evidence for a tendency for European portrait paintings to have the head oriented so that the left side of the face is visible more than the right side. This is particularly the case for female sitters. There is evidence that the left side of the face shows emotion more than the right side does, so it has been proposed that there is a tendency for artists or sitters to want to show more of the emotionality of the sitter. It is shown here that the left-side tendency varies by date. In two studies, large samples were drawn from European gallery collections (study 1) and the National Portrait Gallery in London (study 2). The studies showed a strong left side tendency before 1600, absence of the tendency in the seventeenth and eighteenth centuries, and some recurrence of it in the nineteenth and twentieth centuries, modulated by changing gender differences. These findings show that cultural, historical, or art-historical factors are likely to be involved in determining tendencies in head orientation as well as psychological ones.

Facing the truth: are there hemifacial differences in the communication of trustworthiness?

As the right hemisphere is dominant for emotion processing, the left cheek expresses emotion more intensely than the right cheek. This prompts a leftward bias: people offer the left cheek to communicate emotion and viewers perceive left cheek poses as more emotive. Perceptions of trustworthiness are positively influenced by emotional expressivity, with smiling faces deemed more trustworthy than neutral faces. Thus as the left hemiface is more emotionally expressive than the right, the present study sought to determine whether people offer the left cheek to communicate trustworthiness, and the right to express untrustworthiness. One hundred and twenty-six participants (57 males, 69 females) completed a posing task asking them to read one of two scenarios (randomly assigned: trusted babysitter; untrustworthy car salesman), consider it for 30 seconds, and then pose for a photograph communicating their trustworthiness or untrustworthiness. Contrary to expectation, binary logistic regression results indicated no posing bias for communicating trustworthiness, however people were more likely to offer the left than right cheek when posing to communicate untrustworthiness. The novel finding of a left cheek bias for untrustworthiness is previously unreported, and highlights the need for future investigations of trustworthiness to examine both sides of the trustworthy coin.

Left cheek poses garner more likes: the effect of pose orientation on Instagram engagement

In social media's attention economy "likes" are currency; photos showing faces attract more "likes." Previous research has established a left cheek bias in photos uploaded to social media, but whether left cheek poses induce more engagement than right cheek poses remains to be determined. The present study thus examined whether pose orientation influences the number of "likes" and comments garnered by photos uploaded to Instagram. The top 20 single-user Instagram accounts were identified, and the most recent 10 left and 10 right cheek images were selected, resulting in a total of 400 images. The number of "likes" and comments were tallied for each image, netting over 1 billion "likes" and 14 million comments for analysis. Results confirmed that pose orientation influences audience engagement: left cheek poses garner >10% more "likes" than right cheek poses. Gender did not influence "likes". Comments were not affected by either pose orientation or gender, likely reflecting the different levels of effort and motivations involved in "liking" vs. commenting on an image. These data indicate that a seemingly inconsequential turn of the head profoundly impacts audience engagement: left cheek poses gained >330,000 more "likes", offering clear implications for marketers and others in the social media economy.

Audience size influences actors' anxiety and associated postures on stage

Public performance is a reported source of anxiety. While the relationship between emotion and postural laterality is well-known in animals, few studies have tested the possible link between audience effect, anxiety and head orientation in humans. The Valence-Specific Hypothesis posits that the left/right sides of the brain are specialized for processing positive/negative emotions respectively. Here, actors performed a piece in the presence of small, medium and large audiences. They self-reported feeling more anxious when the audience was large (also confirmed with speech analyses), but the small audience was scored with the lowest preference. We also found that the large audience was associated with the fewest orientations facing the public. Moreover, both large and small audiences were associated with more left-side than right side orientations. Here, actors' emotions influenced lateralized positioning, with a tendency to use the left visual field (i.e. right hemisphere) in more anxious and less preferred situations, supporting the Valence-Specific hypothesis.

Visual attention during the evaluation of facial attractiveness is influenced by facial angles and smile

OBJECTIVE

To examine the changes in visual attention influenced by facial angles and smile during the evaluation of facial attractiveness.

MATERIALS AND METHODS

Thirty-three young adults were asked to rate the overall facial attractiveness (task 1 and 3) or to select the most attractive face (task 2) by looking at multiple panel stimuli consisting of 0°, 15°, 30°, 45°, 60°, and 90° rotated facial photos with or without a smile for three model face photos and a self-photo (self-face). Eye gaze and fixation time (FT) were monitored by the eye-tracking device during the performance. Participants were asked to fill out a subjective questionnaire asking, "Which face was primarily looked at when evaluating facial attractiveness?"

RESULTS

When rating the overall facial attractiveness (task 1) for model faces, FT was highest for the 0° face and lowest for the 90° face regardless of the smile ( P < .01). However, when the most attractive face was to be selected (task 2), the FT of the 0° face decreased, while it significantly increased for the 45° face ( P < .001). When facial attractiveness was evaluated with the simplified panels combined with facial angles and smile (task 3), the FT of the 0° smiling face was the highest ( P < .01). While most participants reported that they looked mainly at the 0° smiling face when rating facial attractiveness, visual attention was broadly distributed within facial angles.

CONCLUSIONS

Laterally rotated faces and presence of a smile highly influence visual attention during the evaluation of facial esthetics.

Fly on the right: Lateral preferences when choosing aircraft seats

A small preference has been observed for people to choose seats on the left of aircraft when booking via an online system. Although this is consistent with pseudoneglect-the known leftward bias in perception and representation-rightward preferences have been commonly observed in seating selection tasks in other environments. Additionally, the previous research in aircraft seating was unable to dissociate a bias to one side of the screen from a bias to one side of the cabin of the aircraft. Here, we present a study in which participants were asked to select seats for a range of fictional flights. They demonstrated a preference for seats on the right of the cabin, irrespective of whether the right of the cabin appeared to either the right or the left of the screen, a preference for seats towards the front of the aircraft and a preference to favour window and aisle seats. This suggests, in contrast to previous research, that participants demonstrated a rightward lateral bias to representations of an aircraft. These results may have implications for our understanding of asymmetries in cognition as well as having potentially important practical implications for airlines.

Selfie-Takers Prefer Left Cheeks: Converging Evidence from the (Extended) selfiecity Database

According to previous reports, selfie takers in widely different cultural contexts prefer poses showing the left cheek more than the right cheek. This posing bias may be interpreted as evidence for a right-hemispheric specialization for the expression of facial emotions. However, earlier studies analyzed selfie poses as categorized by human raters, which raises methodological issues in relation to the distinction between frontal and three-quarter poses. Here, we provide converging evidence by analyzing the (extended) selfiecity database which includes automatic assessments of head rotation and of emotional expression. We confirm a culture- and sex-independent left-cheek bias and report stronger expression of negative emotions in selfies showing the left cheek. These results are generally consistent with a psychobiological account of a left cheek bias in self-portraits but reveal possible unexpected facts concerning the relation between side bias and lateralization of emotional expression.

Left wings to the left: Posing and perceived political orientation

Images of individuals posing with the left cheek toward the camera are rated as more emotionally expressive than images with the right cheek toward the camera, which is theorized to be due to right hemisphere specialization for emotion processing. Liberals are stereotyped as being more emotional than conservatives. In the present study, we presented images of people displaying either leftward or rightward posing biases in an online task, and asked participants to rate people's perceived political orientation. Participants rated individuals portrayed with a leftward posing bias as significantly more liberal than those presented with a rightward bias. These findings support the idea that posing direction is related to perceived emotionality of an individual, and that liberals are stereotyped as more emotional than conservatives. Our results differ from those of a previous study, which found conservative politicians are more often portrayed with a leftward posing bias, suggesting differences between posing output for political parties and perceived political orientation. Future research should investigate this effect in other countries, and the effect of posing bias on perceptions of politicians.

Is Beauty in the Hand of the Writer? Influences of Aesthetic Preferences through Script Directions, Cultural, and Neurological Factors: A Literature Review

Human experience surrounding the appreciation of beauty is not static. Many factors such as script direction and cultural differences directly impact whether, how and why we consider images beautiful. In an earlier study, Pérez González showed that 19th-century Iranian and Spanish professional photographers manifest lateral biases linked to reading writing direction in their compositions. The present paper aims to provide a general review on this topic and intends to highlight the most relevant studies reporting preferences in the appreciation of beauty in individuals with different reading and writing directions and belonging to different cultural backgrounds.

The cheek of a cheater: Effects of posing the left and right hemiface on the perception of trustworthiness

Our cognitive mechanisms are designed to detect cheaters in social exchanges. However, cheater detection can be thwarted by a posed smile, which cheaters display with greater emotional intensity than cooperators. The present study investigated the role of hemifacial asymmetries in the perception of trustworthiness using face photographs with left and right cheek poses. Participants (N = 170) observed face photographs of cheaters and cooperators in an economic game. In the photographs, models expressed happiness or anger and turned slightly to the left or right to show their left or right cheeks to the camera. When the models expressed anger on their faces, cheaters showing the right cheek were rated as less trustworthy than cooperators (irrespective of cheeks shown) and cheaters showing the left cheek. When the models expressed happiness, trustworthiness ratings increased and did not differ between cheaters and cooperators, and no substantial asymmetries were observed. These patterns were replicated even when the face photographs were mirror-reversed. These results suggest that a cheater's fake smile conceals an uncooperative attitude that is displayed in the right hemiface, ultimately disguising cheater detection.

Taking the Perfect Selfie: Investigating the Impact of Perspective on the Perception of Higher Cognitive Variables

Taking selfies is now becoming a standard human habit. However, as a social phenomenon, research is still in the fledgling stage and the scientific framework is sparse. Selfies allow us to share social information with others in a compact format. Furthermore, we are able to control important photographic and compositional aspects, such as perspective, which have a strong impact on the assessment of a face (e.g., demonstrated by the height-weight illusion, effects of gaze direction, faceism-index). In Study 1, we focused on the impact of perspective (left/right hemiface, above/below vs. frontal presentation) on higher cognitive variables and let 172 participants rate the perceived attractiveness, helpfulness, sympathy, dominance, distinctiveness, and intelligence, plus important information on health issues (e.g., body weight), on the basis of 14 3D faces. We could show that lateral snapshots yielded higher ratings for attractiveness compared to the classical frontal view. However, this effect was more pronounced for left hemifaces and especially female faces. Compared to the frontal condition, 30° right hemifaces were rated as more helpful, but only for female faces while faces viewed from above were perceived as significant less helpful. Direct comparison between left vs. right hemifaces revealed no effect. Relating to sympathy, we only found a significant effect for 30° right male hemifaces, but only in comparison to the frontal condition. Furthermore, female 30° right hemifaces were perceived as more intelligent. Relating to body weight, we replicated the so-called “height-weight illusion.” Other variables remained unaffected. In Study 2, we investigated the impact of a typical selfie-style condition by presenting the respective faces from a lateral (left/right) and tilted (lower/higher) vantage point. Most importantly, depending on what persons wish to express with a selfie, a systematic change of perspective can strongly optimize their message; e.g., increasing their attractiveness by shooting from above left, and in contrast, decreasing their expressed helpfulness by shooting from below. We could further extent past findings relating to the height-weight illusion and showed that an additional rotation of the camera positively affected the perception of body weight (lower body weight). We discuss potential explanations for perspective-related effects, especially gender-related ones.

Is trustworthiness lateralized in the face? Evidence from a trust game

A turn of the head can be used to convey or conceal emotion, as the left side of the face is more expressive than the right. As the left cheek moves more when smiling, the present study investigated whether perceived trustworthiness is lateralized to the left cheek, using a trust game paradigm. In Experiment 1, participants were asked to share money with male and female "virtual partners." Left-left or right-right composite faces were used to represent the partners. There were no differences in the amount shared based on composite face, suggesting trustworthiness is not lateralized in the face. However, there was a robust effect whereby female partners were perceived to be significantly more trustworthy than males. In Experiment 2, the virtual partners presented either the left or the right cheek prominently. As in Experiment 1, the amount shared with the partners did not change depending on the cheek presented. Interestingly, female partners were again sent significantly more money than males. We found no support for lateralized trustworthiness in the face, suggesting that asymmetries in the face are not large enough to influence trustworthiness judgements. Instead, more stable facial features, such as sex-typical characteristics, appear to influence perceived trustworthiness.

Consistently Showing Your Best Side? Intra-individual Consistency in #Selfie Pose Orientation

Painted and photographic portraits of others show an asymmetric bias: people favor their left cheek. Both experimental and database studies confirm that the left cheek bias extends to selfies. To date all such selfie studies have been cross-sectional; whether individual selfie-takers tend to consistently favor the same pose orientation, or switch between multiple poses, remains to be determined. The present study thus examined intra-individual consistency in selfie pose orientations. Two hundred selfie-taking participants (100 male and 100 female) were identified by searching #selfie on Instagram. The most recent 10 single-subject selfies for the each of the participants were selected and coded for type of selfie (normal; mirror) and pose orientation (left, midline, right), resulting in a sample of 2000 selfies. Results indicated that selfie-takers do tend to consistently adopt a preferred pose orientation (α = 0.72), with more participants showing an overall left cheek bias (41%) than would be expected by chance (overall right cheek bias = 31.5%; overall midline bias = 19.5%; no overall bias = 8%). Logistic regression modellng, controlling for the repeated measure of participant identity, indicated that sex did not affect pose orientation. However, selfie type proved a significant predictor when comparing left and right cheek poses, with a stronger left cheek bias for mirror than normal selfies. Overall, these novel findings indicate that selfie-takers show intra-individual consistency in pose orientation, and in addition, replicate the previously reported left cheek bias for selfies and other types of portrait, confirming that the left cheek bias also presents within individuals’ selfie corpora.

From Spatial to Social Asymmetry

According to the spatial agency bias model, in Western cultures agentic targets are envisaged as facing and acting rightward, in line with writing direction. In four studies of Italian participants, we examined the symbolic association between agency and the rightward direction (Study 1, N = 96), its spontaneous activation when attributing agency to female and male targets (Study 2, N = 80) or when judging the authenticity of photographs of men and women (Study 3, N = 57), and its possible relation to stereotype endorsement (Study 4, N = 80). In Study 4, we used a conditioning paradigm in which participants learned a counterstereotypical new association; we developed a novel measure to assess the association between gender and spatial direction, namely, the spatial association task. Participants envisaged and cognitively processed male and female targets in line with the spatial agency bias model and reported lower benevolent sexism after learning a new counterstereotypical spatial association. Our findings raise awareness about the biased use of space (and its consequences) in the representation of women and men, so that all people, and especially communicators and policy makers, can actively intervene to promote gender equality. Additional online materials for this article are available to PWQ subscribers on PWQ’s website at http://journals.sagepub.com/doi/suppl/10.1177/0361684316676045

Featural information is sufficient to produce a left cheek bias for happiness perception

People perceive the left cheek as more emotionally expressive than the right. Both configural and featural information enable the evaluation of emotional expressions; whether they make equivalent contributions to the left cheek bias is undetermined. As scrambling faces disrupts configural processing whilst leaving featural information intact, we investigated whether configural information is necessary, or featural information is sufficient, to induce a left cheek bias for emotion perception. Eighty-one participants (65 F, 16 M) viewed two types of left and right cheek image pairs - normal, scrambled - and indicated which image appeared happier (half mirror-reversed to control for perceptual biases). Results indicated a left cheek bias for both normal and scrambled faces, irrespective of mirror reversal. As scrambling faces disrupts configural processing, the fact that the left cheek was perceived as more expressive even when scrambled confirms that differences between the cheeks' featural information are sufficient to induce the left cheek bias.

Reading and writing direction effects on the aesthetic appreciation of photographs

Does reading and writing direction (RWD) influence the aesthetic appreciation of photography? Pérez González showed that nineteenth-century Iranian and Spanish professional photographers manifest lateral biases linked to RWD in their compositions. The present study aimed to test whether a population sample showed similar biases. Photographs with left-to-right (L-R) and right-to-left (R-L) directionality were selected from Pérez González's collections and presented in both original and mirror-reversed forms to Spanish (L-R readers) and Moroccan (R-L readers) participants. In Experiment 1, participants rated each picture for its aesthetic pleasingness. The results showed neither effects of lateral organization nor interactions with RWD. In Experiment 2, each picture and its mirror version were presented together and participants chose the one they liked better. Spaniards preferred rightward versions and Moroccans preferred leftward versions. RWD therefore affects aesthetic impressions of photography in our participants when people pay attention to the lateral spatial dimension of pictures. The observed directional aesthetic preferences were not sensitive to the sex of the model in the photographs, failing to support expectations from the hypotheses of emotionality and agency. Preferences were attributable to the interaction between general scanning strategies and scanning habits linked to RWD.

Composition in portraits: Selfies and wefies reveal similar biases in untrained modern youths and ancient masters

Previous analyses suggest that artists prefer poses showing the left side of the subject's face when composing a portrait, but showing the right side when composing their own self-portrait. There is also some evidence that artists may prefer compositions with key features on the right of the picture. Do these findings generalize to spontaneous, pseudo-artistic productions by individuals with no formal training in painting and art history? To investigate this issue, we tested a sample of 104 British schoolchildren and teenagers (mean age = 13.8 years; 80 females). We analysed posing biases in individual photographic self-portraits ("selfies") as well as of self-portraits including also the portrait of a friend ("wefies"). Our results document a bias for showing the left cheek in selfies, a bias for placing the selfie-taker on the right in wefies, and a bias for showing two left cheeks over two right cheeks, again in wefies. These biases are reminiscent of what has been reported for selfies in adult non-artists and for portraits and self-portraits by artists in the 16th-18th centuries. Thus, these results provide new evidence in support of a biological basis for side biases in portraits and self-portraits independently of training and expertise.

Take your seats: leftward asymmetry in classroom seating choice

Despite an overall body symmetry, human behavior is full of examples of asymmetry, from writing or gesturing to kissing and cradling. Prior research has revealed that theatre patrons show a bias towards sitting on the right side of a movie theatre. Two competing theories have attempted to explain this seating asymmetry: one posits that expectation of processing demand drives the bias; the other posits that basic motor asymmetries drive the bias. To test these theories we assessed the real-world classroom seating choices of university students using photographs. A bias for students to choose seats on the left side of the classroom was observed, in contrast to the right side bias observed in theatre seating studies. These results provide evidence in support of a processing-expectation bias.

Can Population-Level Laterality Stem from Social Pressures? Evidence from Cheek Kissing in Humans

Despite extensive research, the origins and functions of behavioural laterality remain largely unclear. One of the most striking unresolved issues is the fact that laterality generally occurs at the population-level. Why would the majority of the individuals of a population exhibit the same laterality, while individual-level laterality would yet provide the advantages in terms of improving behavioural efficiency? Are social pressures the key factor? Can social pressures induce alignment of laterality between the individuals of a population? Can the effect of social pressures overpass the effect of other possible determining factors (e.g. genes)? We tested this important new hypothesis in humans, for the first time. We asked whether population-level laterality could stem from social pressures. Namely, we assessed social pressures on laterality in an interactive social behaviour: kissing on the cheek as a greeting. We performed observations in 10 cities of France. The observations took place in spots where people of the city meet and greet each other. We showed that: a) there is a population-level laterality for cheek kissing, with the majority of individuals being aligned in each city, and b) there is a variation between populations, with a laterality that depends on the city. These results were confirmed by our complementary data from questionnaires and internet surveys. These findings show that social pressures are involved in determining laterality. They demonstrate that population-level laterality can stem from social pressures.

Selfie and the city: a world-wide, large, and ecologically valid database reveals a two-pronged side bias in naïve self-portraits

Self-portraits are more likely to show the artist's right than left cheek. This phenomenon may have a psychobiological basis: Self-portraitists often copy their subject from mirrors and, if they prefer to present their left cheek (more expressive due to right-lateralization of emotions) to the mirror, this would result in a right-cheek bias in the painting. We tested this hypothesis using SelfieCity (3200 selfies posted on Instagram from December 4 through 12, 2013 from New York, Sao Paulo, Berlin, Moskow, and Bangkok), which includes two selfie-taking styles: a "standard" (photograph of selfie-taker) and a "mirror" (photograph of mirror reflection of selfie-taker) style. We show that the first style reveals a left cheek bias, whereas the second reveals a right cheek bias. Thus side biases observed in a world-wide, large, and ecologically valid database of naïve self-portraits provide strong support for a role of psychobiological factors in the artistic composition of self-portraits.