The two sides of beauty: Laterality and the duality of facial attractiveness

We hypothesized that facial attractiveness represents a dual judgment, a combination of reward-based, sexual processes, and aesthetic, cognitive processes. Herein we describe a study that demonstrates that sexual and nonsexual processes both contribute to attractiveness judgments and that these processes can be dissociated. Female participants rated the general attractiveness of faces presented in either their left or right visual field. In order to examine sexual and nonsexual components of these judgments, general attractiveness ratings were correlated with ratings of these same faces made by two independent groups of raters in two specific contexts, one sexual and one nonsexual. Based on an items analysis, partial correlation coefficients were computed for each individual and used as the dependent variable of interest in a 2 (laterality: right, left) by 2 (context: sexual, nonsexual) ANOVA. This analysis revealed an interaction such that faces rated in a sexual context better predicted attractiveness ratings of faces shown in the left than right visual field, whereas faces rated in a nonsexual context better predicted attractiveness of faces shown in the right than left visual field. This finding is consistent with the assertion that sexual and nonsexual preferences involve predominantly lateralized processing routes that independently contribute to what is perceived to be attractive.     

The role of holistic processing in judgments of facial attractiveness

Previous work has demonstrated that facial identity recognition, expression recognition, gender categorisation, and race categorisation rely on a holistic representation. Here we examine whether a holistic representation is also used for judgments of facial attractiveness. Like past studies, we used the composite paradigm to assess holistic processing (Young et al 1987, Perception 16 747-759). Experiment 1 showed that top halves of upright faces are judged to be more attractive when aligned with an attractive bottom half than when aligned with an unattractive bottom half. To assess whether this effect resulted from holistic processing or more general effects, we examined the impact of the attractive and unattractive bottom halves when upright halves were misaligned and when aligned and misaligned halves were presented upside-down. The bottom halves had no effect in either condition. These results demonstrate that the perceptual processes underlying upright facial-attractiveness judgments represent the face holistically. Our findings with attractiveness judgments and previous demonstrations involving other aspects of face processing suggest that a common holistic representation is used for most types of face processing.     

Multiple perceptual strategies used by macaque monkeys for face recognition

Successful integration of individuals in macaque societies suggests that monkeys use fast and efficient perceptual mechanisms to discriminate between conspecifics. Humans and great apes use primarily holistic and configural, but also feature-based, processing for face recognition. The relative contribution of these processes to face recognition in monkeys is not known. We measured face recognition in three monkeys performing a visual paired comparison task. Monkey and humans faces were (1) axially rotated, (2) inverted, (3) high-pass filtered, and (4) low-pass filtered to isolate different face processing strategies. The amount of time spent looking at the eyes, mouth, and other facial features was compared across monkey and human faces for each type of stimulus manipulation. For all monkeys, face recognition, expressed as novelty preference, was intact for monkey faces that were axially rotated or spatially filtered and was supported in general by preferential looking at the eyes, but was impaired for inverted faces in two of the three monkeys. Axially rotated, upright human faces with a full range of spatial frequencies were also recognized, however, the distribution of time spent exploring each facial feature was significantly different compared to monkey faces. No novelty preference, and hence no inferred recognition, was observed for inverted or low-pass filtered human faces. High-pass filtered human faces were recognized, however, the looking pattern on facial features deviated from the pattern observed for monkey faces. Taken together these results indicate large differences in recognition success and in perceptual strategies used by monkeys to recognize humans versus conspecifics. Monkeys use both second-order configural and feature-based processing to recognize the faces of conspecifics, but they use primarily feature-based strategies to recognize human faces.     

Computational models of facial attractiveness judgments

We designed two computational models to replicate human facial attractiveness ratings. The primary model used partial least squares (PLS) to identify image factors associated with facial attractiveness from facial images and attractiveness ratings of those images. For comparison we also made a model similar to previous models of facial attractiveness, in that it used manually derived measurements between features as inputs, though we took the additional step of dimensionality reduction via principal component analysis (PCA) and weighting of PCA dimensions via a perceptron. Strikingly, both models produced estimates of facial attractiveness that were indistinguishable from human ratings. Because PLS extracts a small number of image factors from the facial images that covary with attractiveness ratings of the images, it is possible to determine the information used by the model. The image factors that the model discovered correspond to two of the main contemporary hypotheses of averageness judgments: facial attractiveness and sexual dimorphism. In contrast, facial symmetry was not important to the model, and an explicit feature-based measurement of symmetry was not correlated with human judgments of facial attractiveness. This provides novel evidence for the importance of averageness and sexual dimorphism, but not symmetry, in human judgments of facial attractiveness.     

Configural processing and perceptions of head tilt

Configural processing is important for face recognition, but its role in other types of face processing is unclear. In the present study, participants made judgments of head tilt for faces in which the vertical position of the internal facial region was varied. We found a highly reliable relationship between inner-face position and perceived head tilt. We also found that changes in inner-face position affected the perceived dimensions of an individual unchanged facial feature: compared to control faces, nearly two-thirds of faces in which the features had been moved down were judged to have a longer nose. This finding suggests an early integration of configural and featural processing to create a stable holistic percept of the face. The demonstration of holistic processing at a basic perceptual level (as opposed to during face recognition) is important as it constrains possible models of the relationships between featural and configural processing.     

面孔吸引力的整体表征及其动态性增强

面孔作为一种高级的视觉刺激,在人际交往中有着无可替代的作用。其中,面孔吸引力更是影响着日常生活的重要社交决策,如择偶、交友、求职、社会交换等。长久以来,研究者们从面孔特征、社会信息和观察者因素等角度不断探索着人们对静态面孔吸引力的感知,且多从进化角度加以解释。但是,人们如何表征面孔吸引力以及其动态性增强机制仍未可知。本项目通过两个研究,分别从面孔吸引力的整体表征,以及面孔动态性通过影响整体加工、影响对整体信息和特征信息的注意、以及影响社会信息来增强吸引力,从这两个角度尝试回答这一问题。在研究1中,本项目从整体加工的角度探索了面孔吸引力的认知表征。研究1.1通过评分任务和适应范式探索高空间频率（更多局部特征）和低空间频率（更多整体特征）对面孔吸引力的影响,旨在从空间频率探讨面孔吸引力的整体表征。研究1.2通过操纵面孔对称性和面孔常态性探索面孔常态性在面孔对称性和面孔吸引力间的中介作用,探讨面孔吸引力的常态构型表征。研究1.3引入“三庭五眼”这一中国传统面孔审美理论,通过评分任务和适应范式研究“三庭五眼” 构型是否符合中国人对高吸引力中国面孔的表征,以此探讨面孔吸引力的整体表征。研究1.4通过评分任务和适应范式考察局部面孔遮挡是否促进整体面孔吸引力,以及这种促进作用是否由于人们通过局部特征“脑补”出了完整面孔。研究2从整体加工、注意和生命力的角度探讨面孔吸引力的动态性增强机制。研究2.1使用合成效应范式测量动态面孔吸引力的整体加工,探索动静态面孔的吸引力差异是否源于其整体加工程度的不同。研究2.2使用注意分散范式,并结合眼动技术,探讨人们对动静态面孔的注视模式是否存在差异,这种差异是否能解释动态面孔吸引力的增强。研究2.3结合问卷法、实验法和结构方程模型,考察了生命力这一社会因素对动静态面孔吸引力的影响。本项目探讨了面孔吸引力的认知表征以及其动态性增强机制,有助于我们进一步理解人们对面孔吸引力的认知加工以及人类欣赏美这一高级智能。同时,本项目的结果对于日常人际交往和面孔吸引力相关算法的优化等方面也有潜在的应用价值。     

What aspects of face processing are impaired in developmental prosopagnosia?

Developmental prosopagnosia (DP) is a severe impairment in identifying faces that is present from early in life and that occurs despite no apparent brain damage and intact visual and intellectual function. Here, we investigated what aspects of face processing are impaired/spared in developmental prosopagnosia by examining a relatively large group of individuals with DP (n = 8) using an extensive battery of well-established tasks. The tasks included measures of sensitivity to global motion and to global form, detection that a stimulus is a face, determination of its sex, holistic face processing, processing of face identity based on features, contour, and the spacing of features, and judgments of attractiveness. The DP cases showed normal sensitivity to global motion and global form and performed normally on our tests of face detection and holistic processing. On the other tasks, many DP cases were impaired but there was no systematic pattern. At least half showed deficits in processing of facial identity based on either the outer contour or spacing of the internal features, and/or on judgments of attractiveness. Three of the eight were impaired in processing facial identify based on the shape of internal features. The results show that DP is a heterogeneous condition and that impairment in recognizing faces cannot be predicted by poor performance on any one measure of face processing.     

Intuition versus analysis: Strategy and experience in complex everyday problem solving

Research on dual processes in cognition has shown that explicit, analytical thought is more powerful and less vulnerable to heuristics and biases than is implicit, intuitive thought. However, several studies have shown that holistic, intuitive processes can outperform analysis, documenting the disruptive effects of hypothesis testing, think-aloud protocols, and analytical judgments. To examine the effects of intuitive versus analytical strategy and level of experience on problem solving, 1st- through 4th-year undergraduates solved problems dealing with college life. The results of two studies showed that the appropriateness of strategy depends on the problem solver's level of experience. Analysis was found to be an appropriate strategy for more experienced individuals, whereas novices scored best when they took a holistic, intuitive perspective. Similar effects of strategy were found when strategy instruction was manipulated and when participants were compared on the basis of strategy preference. The implications for research on problem solving, expertise, and dual-process models are discussed.     

Processing orientation and emotion recognition

There is evidence that some emotional expressions are characterized by diagnostic cues from individual face features. For example, an upturned mouth is indicative of happiness, whereas a furrowed brow is associated with anger. The current investigation explored whether motivating people to perceive stimuli in a local (i.e., feature-based) rather than global (i.e., holistic) processing orientation was advantageous for recognizing emotional facial expressions. Participants classified emotional faces while primed with local and global processing orientations, via a Navon letter task. Contrary to previous findings for identity recognition, the current findings are indicative of a modest advantage for face emotion recognition under conditions of local processing orientation. When primed with a local processing orientation, participants performed both significantly faster and more accurately on an emotion recognition task than when they were primed with a global processing orientation. The impacts of this finding for theories of emotion recognition and face processing are considered.     

眼睛区域构型信息与特征信息的跨维共变增益效应及其加工特异性

面孔知觉可能在区域尺度上发生多维信息整合, 但迄今无特异性实验证据。本研究在两个实验中操纵面孔眼睛区域或嘴巴区域的单维构型或特征信息, 测量人们觉察单维变化或跨维共变的敏感度, 以此检测面孔区域尺度上的多维信息整合有何现象与规律, 进而揭示面孔知觉的多维信息整合机制。实验获得3个发现：(1)正立面孔眼睛区域的信息变化觉察呈现出“跨维共变增益效应”, 跨维信息共变觉察的敏感度显著高于任意一种单维信息变化觉察的敏感度; (2)“跨维共变增益效应”只在正立面孔的眼睛区域出现, 在倒置面孔的眼睛区域、正立面孔的嘴巴区域或倒置面孔的嘴巴区域都没有出现, 因此具有面孔区域特异性和面孔朝向特异性; (3)就单维信息变化觉察而言, 眼睛区域的敏感度不会受到面孔倒置的损伤, 但是嘴巴区域的敏感度会受到面孔倒置的显著损伤。综合可知, 面孔知觉确实会发生区域尺度上的信息整合, 它不是普遍性的信息量效应, 而是特异性的眼睛效应(只发生在正立面孔的眼睛区域)。这是面孔整体加工(face holistic processing)在单维信息分辨和多维信息整合之间建立联系的必经环节。这提示我们对全脸多维信息知觉整合的理解需要从传统的面孔整体加工假设升级到以眼睛为中心的层级化多维信息整合算法(a hierarchical algorithm for multi-dimensional information integration)。     

Holistic processing underlies gender judgments of faces

In three experiments, we investigated whether holistic processing underlies gender judgments about faces. Chinese participants were asked to make gender judgments for inverted, scrambled, or composite faces. Results showed that judgments were dramatically impaired by these manipulations (as compared with performance for normal upright faces), demonstrating three hallmark effects of holistic face processing that have been observed in perception of face identity. Whether the test faces were Chinese or Caucasian showed no effect on holistic processing of gender perception, in contrast to studies of identity analysis. These results suggest that holistic processing is a general mechanism for different aspects of face perception and are consistent with the idea that physiognomic properties that determine the gender of a face are universal, rather than race specific.     

Female sexual orientation is perceived accurately, rapidly, and automatically from the face and its features

Whereas previous work has shown that male sexual orientation can be accurately and rapidly perceived from the human face and its individual features, no study has examined the judgment of female sexual orientation. To fill this gap, the current work examined the accuracy, speed, and automaticity of judgments of female sexual orientation from the face and from facial features. Study 1 showed that female sexual orientation could be accurately judged from the face and from just eyes without brows and limited to the outer canthi. Study 2 then examined the speed and efficiency of these judgments, showing that judgments of the faces following very brief, near subliminal (40 ms) exposures were significantly better than chance guessing. Finally, Study 3 tested the automaticity of judgments of female sexual orientation by examining the effects of deliberation on accuracy. Participants who made snap judgments of female sexual orientation were significantly more accurate than participants who made thoughtful and deliberated judgments. These data therefore evidence a robust, reliable, and automatic capacity for extracting information about female sexual orientation from nonverbal cues in the face.     

The composite face effect in six-year-old children: Evidence of adult-like holistic face processing

Holistic processing (i.e., gluing facial features together into a gestalt) is a hallmark of adults’ expert face recognition. Children make more errors than adults on a variety of face processing tasks even during adolescence. To determine whether this slow development can be attributed to immature holistic processing of unfamiliar faces, we tested 6-year-old children (n=24) with a classic measure of adults’ holistic processing, the composite face effect: They made same/different judgements about the top halves of face pairs when each top half was combined with a different bottom half, with which it was aligned (so that holistic processing creates the impression of a different face) or misaligned (a manipulation that disrupts holistic processing). Six-year-olds showed an adult-like composite face effect: Like adults, they made 26% more errors on aligned trials than on misaligned trials. These results suggest that the improvements after age 6 in the recognition of the facial identity are not caused by the onset or increasing strength of holistic face processing.     

Differences in holistic processing do not explain cultural differences in the recognition of facial expression

The aim of this study was to investigate the causes of the own-race advantage in facial expression perception. In Experiment 1, we investigated Western Caucasian and Chinese participants’ perception and categorization of facial expressions of six basic emotions that included two pairs of confusable expressions (fear and surprise; anger and disgust). People were slightly better at identifying facial expressions posed by own-race members (mainly in anger and disgust). In Experiment 2, we asked whether the own-race advantage was due to differences in the holistic processing of facial expressions. Participants viewed composite faces in which the upper part of one expression was combined with the lower part of a different expression. The upper and lower parts of the composite faces were either aligned or misaligned. Both Chinese and Caucasian participants were better at identifying the facial expressions from the misaligned images, showing interference on recognizing the parts of the expressions created by holistic perception of the aligned composite images. However, this interference from holistic processing was equivalent across expressions of own-race and other-race faces in both groups of participants. Whilst the own-race advantage in recognizing facial expressions does seem to reflect the confusability of certain emotions, it cannot be explained by differences in holistic processing.     

Memory for faces: Encoding and retrieval operations

The reliable finding that trait judgments of faces yield better recognition memory than do feature judgments of faces is conceptualized as an encoding-specificity effect. Specifically, both trait-judgment encodings of faces and face-recognition tests are argued to be holistic, involving topographical information with between-feature processing. Consistent with the concept that encoding and retrieval operations interact to produce retrieval success, it was expected that a memory-for-face test using the Identi-kit (which requires reconstructions of the face at a feature level of analysis) would show trait-encoding tasks to be inferior to feature-encoding tasks. Eighty subjects were assigned randomly to judge a face on 10 trait dimensions (e.g., honesty-dishonesty) or on 10 feature dimensions (e.g., narrow nose-wide nose) and subsequently attempted to recognize the target among five distractors or to reconstruct the face from an Identi-kit. The significant interaction between encoding and retrieval operations indicated that the face was best identified under trait-encoding conditions but best reconstructed under feature-encoding conditions. The match between trait encoding and recognition in yielding high memory performance suggests strongly that trait judgments foster holistic processing of faces (i.e., interfeature topographical information is p-art of the context) and that the recognition of faces also is holistic. Finally, the utility of the feature- vs. holistic-processing distinction is questioned, and an alternative is proposed.     

Normal perception of Mooney faces in developmental prosopagnosia: Evidence from the N170 component and rapid neural adaptation

Individuals with developmental prosopagnosia (DP) have a severe difficulty recognizing the faces of known individuals in the absence of any history of neurological damage. These recognition problems may be linked to selective deficits in the holistic/configural processing of faces. We used two‐tone Mooney images to study the processing of faces versus non‐face objects in DP when it is based on holistic information (or the facial gestalt) in the absence of obvious local cues about facial features. A rapid adaptation procedure was employed for a group of 16 DPs. Naturalistic photographs of upright faces were preceded by upright or inverted Mooney faces or by Mooney houses. DPs showed face‐sensitive N170 components in response to Mooney faces versus houses, and N170 amplitude reductions for inverted as compared to upright Mooney faces. They also showed the typical pattern of N170 adaptation effects, with reduced N170 components when upright naturalistic test faces were preceded by upright Mooney faces, demonstrating that the perception of Mooney and naturalistic faces recruits shared neural populations. Our findings demonstrate that individuals with DP can utilize global information about face configurations for categorical discriminations between faces and non‐face objects, and suggest that face processing deficits emerge primarily at more fine‐grained higher level stages of face perception.     

The inversion effect reveals species differences in face processing

Face recognition is a complex skill that requires the integration of facial features across the whole face, e.g., holistic processing. It is unclear whether, and to what extent, other species process faces in a manner that is similar to humans. Previous studies on the inversion effect, a marker of holistic processing, in nonhuman primates have revealed mixed results in part because many studies have failed to include alternative image categories necessary to understand whether the effects are truly face-specific. The present study re-examined the inversion effect in rhesus monkeys and chimpanzees using comparable testing methods and a variety of high quality stimuli including faces and nonfaces. The data support an inversion effect in chimpanzees only for conspecifics' faces (expert category), suggesting face-specific holistic processing similar to humans. Rhesus monkeys showed inversion effects for conspecifics, but also for heterospecifics' faces (chimpanzees), and nonfaces images (houses), supporting important species differences in this simple test of holistic face processing.     

Disrupting perceptual grouping of face parts impairs holistic face processing

Face perception is widely believed to involve integration of facial features into a holistic perceptual unit, but the mechanisms underlying this integration are relatively unknown. We examined whether perceptual grouping cues influence a classic marker of holistic face perception, the “composite-face effect.” Participants made same–different judgments about a cued part of sequentially presented chimeric faces, and holistic processing was indexed as the degree to which the task-irrelevant face halves impacted performance. Grouping was encouraged or discouraged by adjusting the backgrounds behind the face halves: Although the face halves were always aligned, their respective backgrounds could be misaligned and of different colors. Holistic processing of face, but not of nonface, stimuli was significantly reduced when the backgrounds were misaligned and of different colors, cues that discouraged grouping of the face halves into a cohesive unit (Exp. 1). This effect was sensitive to stimulus orientation at short (200 ms) but not at long (2,500 ms) encoding durations, consistent with the previously documented temporal properties of the holistic processing of upright and inverted faces (Exps. 2 and 3). These results suggest that grouping mechanisms, typically involved in the perception of objecthood more generally, might contribute in important ways to the holistic perception of faces.     

Modeling face identification processing in children and adults

Two face identification experiments were carried out to study whether and how children (5-year-olds) and adults integrate single facial features to identify faces. Using the paradigm of the Fuzzy Logical Model of Perception each experiment used the same expanded factorial design, with three levels of eyes variations crossed with three levels of mouth variations as well as their corresponding half-face conditions. In Experiment 1, an integration of facial features was observed in adults only. But, in adjusting the salience of the features varied, the results of Experiment 2 indicate that children and adults evaluated and integrated information from both features to identify a face. A weighted Fuzzy Logical Model of Perception fit the judgments significantly better than a Single Channel Model and questions previous claims of holistic face processing. Although no developmental differences in the stage of the integration of facial information were observable, differences between children and adults appeared in the information used for face identification.     

The effect of face orientation on holistic processing

Holistic processing, a hallmark of face processing, can be measured by the composite face effect: adults have difficulty recognising the top half of a face when it is aligned with a new bottom half, unless holistic processing is disrupted by misaligning the two halves. Like the recognition of facial identity, holistic processing is impaired when faces are inverted. To obtain a more refined measure of the influence of orientation on holistic face processing, we administered the composite face task to adults at each of seven orientations. In both experiment 1 (in which orientations were randomly intermixed) and experiment 2 (in which orientations were blocked), the composite face effect decreased linearly with rotation. We conclude that holistic processing is tuned to upright faces, diminishes as faces deviate from upright, and becomes insignificant once faces reach a sideways orientation. We propose a hierarchical model of face perception in which linear decreases in holistic processing underlie qualitative shifts in other aspects of face perception.