Configural face processing develops more slowly than featural face processing

Expertise in face processing takes many years to develop. To determine the contribution of different face-processing skills to this slow development, we altered a single face so as to create sets of faces designed to measure featural, configural, and contour processing. Within each set, faces differed only in the shape of the eyes and mouth (featural set), only in the spacing of the eyes and mouth (spacing set), or only in the shape of the external contour (contour set). We presented adults, and children aged 6, 8, and 10 years, with pairs of upright and inverted faces and instructed them to indicate whether the two faces were the same or different. Adults showed a larger inversion effect for the spacing set than for the featural and external contour sets, confirming that the spacing set taps configural processing. On the spacing set, all groups of children made more errors than adults. In contrast, on the external contour and featural sets, children at all ages were almost as accurate as adults, with no significant difference beginning at age 6 on the external contour set and beginning at age 10 on the featural set. Overall, the results indicate that adult expertise in configural processing is especially slow to develop.     

Configural processing and face viewpoint

Configural/holistic processing, a key property of face recognition, has previously been examined only for front views of faces. Here, 6 experiments tested front (0 degrees ), three-quarter (45 degrees ), and profile views (90 degrees ), using composite and peripheral inversion tasks. Results showed an overall disadvantage in identifying profiles. This arose entirely from part-based processing: View effects were as strong for disrupted-configuration faces (inverted, misaligned, scrambled) as for normal-configuration faces. In contrast, configural processing (aligned-misaligned difference, upright-inverted difference) was equally strong for all views under both clear and degraded viewing conditions. Findings argue that, although part-based processing is weakened by lower natural frequency of the profile view and/or occlusion of key face features, neither of these variables influences configural processing. This suggests that the functional role of configural processing is to allow reliable face identification despite substantial variance in local information across different natural images. Results also show that only image-plane rotation of faces (upright through inverted) affects configural processing; the contrast with depth rotation has potential implications for understanding the origin of configural processing in terms of innate versus experience-based expertise contributions.     

Configural face processing: a meta-analytic survey

In the field of face processing, the configural hypothesis is defended by many researchers. It is often claimed that this thesis is robustly supported by a large number of experiments exploring the face-inversion effect, the composite face effect, the face superiority effect, and the negative face effect. However, this claim is generally based on a rudimentary and approximate vote-counting approach. In this paper, I use meta-analyses to examine the relevant literature in more depth. The analysis supports the vote-counting argument.     

Remembering parts and wholes: Configural processing in face recollection

In two experiments, we examined the role of configural processing on states of awareness in face recognition. Configural processing was manipulated by presenting upright and inverted faces during study and test. After studying facial photographs of humans (Experiment 1) and horses (Experiment 2), participants provided a remember/know judgement for each recognised test face. In both experiments, disrupted configural processing had selective effects on states of awareness, so that inversion reduced remember, but not know, responses. Experiment 2 revealed disproportionate inversion effects in that the difference in remember responses between upright and inverted items was significant for human faces but not horses. These findings suggest that configural processing facilitates explicit recollection by providing a distinctive combination of nonsalient event attributes.     

Configural processing in the perception of eye-gaze direction

Traditional accounts of gaze perception emphasise the geometric or configural cues present in the eye; the position of the iris in relation to the corner of the eye, for example. This kind of geometric account has been supported, in part, by findings that gaze judgments are impaired in faces rotated through 180 degrees, a manipulation known to disrupt the processing of relations between facial elements. However, studies involving this manipulation have confounded inversion of the face context with inversion of the eye region. The effects of inversion might therefore have been caused by a disruption of the computation of gaze direction from the eye region itself and/or a disruption of the influence that face context might exert on gaze processing. In the experiment reported here we independently manipulated eye orientation and the orientation of the face context, and measured participants' sensitivity to gaze direction. Performance was severely affected by inversion of the eyes, regardless of the orientation of the face, whereas face inversion had no significant effect on gaze sensitivity. Previous reports of a face-inversion effect on gaze perception can therefore be attributed to inversion of the eye region itself which, we suggest, disrupts some form of configural or relational processing that is normally involved in the computation of eye-gaze direction.     

Features are also important: contributions of featural and configural processing to face recognition

It has been suggested that face recognition is primarily based on configural information, with featural information playing little or no role. We investigated this idea by comparing the prototype effect for face prototypes that emphasized either featural or configural processing. In Experiment 1, participants showed a tendency to commit false alarms in response to nonstudied prototypes, and this tendency was equivalent for featural and configural prototypes. Experiment 2 replicated this finding, and provided support for the assumption that the two types of prototypes differed in terms of featural and configural processing: Face inversion eliminated the prototype effect for configural prototypes but not for featural prototypes. These results suggest that both featural and configural processing make important contributions to face recognition, and that their effects are dissociable.     

Evidence of a shift from featural to configural face processing in infancy

Two experiments examined whether 4-, 6-, and 10-month-old infants process natural looking faces by feature, i.e. processing internal facial features independently of the facial context or holistically by processing the features in conjunction with the facial context. Infants were habituated to two faces and looking time was measured. After habituation they were tested with a habituation face, a switch-face, or a novel face. In the switch-faces, the eyes and mouth of the habituation faces were switched. The results showed that the 4-month-olds processed eyes and mouth by feature, whereas the 10-month-olds processed both features holistically. The 6-month-olds were in a transitional stage where they processed the mouth holistically but the eyes still as a feature. Thus, the results demonstrated a shift from featural to holistic processing in the age range of 4 to 10 months.     

Configural face encoding and spatial frequency information

Configural relations and a critical band of spatial frequencies (SFs) in the middle range are particularly important for face recognition. We report the results of four experiments in which the relationship between these two types of information was examined. In Experiments 1, 2A, and 2B, the face inversion effect (FIE) was used to probe configural face encoding. Recognition of upright and inverted faces and nonface objects was measured in four conditions: a no-filter condition and three SF conditions (low, medium, and high frequency). We found significant FIEs of comparable magnitudes for all frequency conditions. In Experiment 3, discrimination of faces on the basis of either configural or featural modifications was measured under the same four conditions. Although the ability to discriminate configural modifications was superior in the medium-frequency condition, so was the ability to discriminate featural modifications. We conclude that the band of SF that is critical for face recognition does not contribute preferentially to configural encoding.     

A whole face is more than the sum of its halves: Interactive processing in face perception

Facial information is processed interactively. Yet, such interactive processing has been examined for discrimination of face parts rather than complete faces. Here we assess interactive processing using a novel paradigm in which subjects discriminate complete faces. Face stimuli, which comprise unilateral facial information (hemifaces) or bilateral facial information from one face (consistent) or two different faces (inconsistent), are shown centrally in a face‐matching task. If each half of a complete face is processed independently, accuracy for complete faces can be predicted by the union of accuracies for right and left hemifaces. However, accuracy exceeded this independence prediction for consistent faces (facilitation) and fell below the prediction for inconsistent faces (interference). These effects were reduced or absent for inverted faces. Our findings are consistent with reports of stronger interactive processing for upright than for inverted faces and they quantify effects of interactive processing on the discrimination of complete faces.     

Influence of subjective difficulty on the degree of configural and featural processing in face recognition1

This study aimed to assess the effect of subjective difficulty on the degree of featural or configural processing in face recognition. It could be assumed that featural processing is analytic processing ( Peterson & Rhodes, 2003 ), while configural processing is automatic processing ( Dunning & Stern, 1994 ). It has been suggested that task difficulty affected the automaticity of processing. Task difficulty was manipulated using a number of alternatives or time pressure. Subjective difficulty could also affect the automaticity of processing. If so, then subjective difficulty may in turn affect the degree of featural or configural processing. Participants in a difficult condition were given instructions mentioning that the face‐recognition task was difficult, while participants in the control condition were given no such instruction. The amount of retrieved featural information in the former condition was less than that in the latter. These results suggested that the degree of featural processing decreased when the participants found the task difficult.     

Emotion recognition: The role of featural and configural face information

Several studies investigated the role of featural and configural information when processing facial identity. A lot less is known about their contribution to emotion recognition. In this study, we addressed this issue by inducing either a featural or a configural processing strategy (Experiment 1) and by investigating the attentional strategies in response to emotional expressions (Experiment 2). In Experiment 1, participants identified emotional expressions in faces that were presented in three different versions (intact, blurred, and scrambled) and in two orientations (upright and inverted). Blurred faces contain mainly configural information, and scrambled faces contain mainly featural information. Inversion is known to selectively hinder configural processing. Analyses of the discriminability measure (A′) and response times (RTs) revealed that configural processing plays a more prominent role in expression recognition than featural processing, but their relative contribution varies depending on the emotion. In Experiment 2, we qualified these differences between emotions by investigating the relative importance of specific features by means of eye movements. Participants had to match intact expressions with the emotional cues that preceded the stimulus. The analysis of eye movements confirmed that the recognition of different emotions rely on different types of information. While the mouth is important for the detection of happiness and fear, the eyes are more relevant for anger, fear, and sadness.     

The perception of face gender: The role of stimulus structure in recognition and classification

The perception of face gender was examined in the context of extending “face space” models of human face representations to include the perceptual categories defined by male and female faces. We collected data on the recognizability, gender classifiability (reaction time to classify a face as male/female), attractiveness, and masculinity/femininity of individual male and female faces. Factor analyses applied separately to the data for male and female faces yielded the following results. First, for both male and female faces, the recognizability and gender classifiability of faces were independent—a result inconsistent with the hypothesis that both recognizability and gender classifiability depend on a face’s “distance” from the subcategory gender prototype. Instead, caricatured aspects of gender (femininity/masculinity ratings) related to the gender classifiability of the faces. Second, facial attractiveness related inversely to face recognizability for male, but not for female, faces—a result that resolves inconsistencies in previous studies. Third, attractiveness and femininity for female faces were nearly equivalent, but attractiveness and masculinity for male faces were not equivalent. Finally, we applied principal component analysis to the pixel-coded face images with the aim of extracting measures related to the gender classifiability and recognizability of individual faces. We incorporated these model-derived measures into the factor analysis with the human rating and performance measures.     

Temporal integration in face perception: evidence of configural processing of temporally separated face parts

Temporal integration is the process by which temporally separated visual components are combined into a unified representation. Although this process has been studied in object recognition, little is known about temporal integration in face perception and recognition. In the present study, the authors investigated the characteristics and time boundaries of facial temporal integration. Whole faces of nonfamous and famous people were segmented horizontally into 3 parts and presented in sequence, with varying interval lengths between parts. Inversion and misalignment effects were found at short intervals (0-200 ms). Moreover, their magnitude was comparable to those found with whole-face presentations. These effects were eliminated, or substantially reduced, when the delay interval was 700 ms. Order of parts presentation did not influence the pattern of inversion effects obtained within each temporal delay condition. These results demonstrate that temporal integration of faces occurs in a temporary and limited visual buffer. Moreover, they indicate that only integrated faces can undergo configural processing.     

情绪概念加工与情绪面孔知觉的相互影响

通过3个实验探讨情绪概念加工与情绪面孔知觉是否存在相互影响, 以及加工深度对两者关系的影响。实验1采用情绪面孔启动范式, 探讨较深的情绪概念加工层面对情绪概念与情绪面孔的关系的影响。实验2更改概念任务, 探讨较浅的概念加工层面对两者关系的影响。实验3缩短启动面孔呈现时间, 探讨较浅的面孔知觉层面对两者关系的影响。通过研究主要得出以下结论：(1)情绪概念加工与情绪面孔知觉确实存在相互影响; (2)概念加工深度影响两者关系的方向性, 在较深的概念加工层面, 两者的关系是双向的, 在较浅的概念加工层面, 两者的关系是单向的; (3)知觉加工深度也影响两者关系的方向性, 在较深的知觉加工层面, 两者的关系是双向的, 在较浅的知觉加工层面, 没有发现两者的相互影响。本研究为抽象概念的具身表征提供了实证支持。     

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.     

Evidence against a central bottleneck during the attentional blink: multiple channels for configural and featural processing

When a visual target is identified, there is a period of several hundred milliseconds when the processing of subsequent targets is impaired, a phenomenon labeled the attentional blink (AB). The emerging consensus is that the identification of a visual target temporarily occupies a limited attentional resource that is essential for all visual perception. The present results challenge this view. With the same digit discrimination task that impaired subsequent letter discrimination for several hundred milliseconds, we found no disruption of subsequent face discrimination. These results suggest that all stimuli do not compete for access to a single resource for visual perception. We propose a multi-channel account of interference in the AB paradigm.     

Configural processing at birth: evidence for perceptual organisation

We report a series of ten experiments aimed to investigate the newborn's ability to discriminate the components of a visual pattern and to process the visual information that specifies the global configuration of a stimulus. The results reveal that: (i) newborn babies are able to distinguish individual elements of a stimulus (experiments 1A, 1B, 1C, and 1D); (ii) they can group individual elements into a holistic percept on the basis of Gestalt principles (experiments 2A and 3A); (iii) their spontaneous preferences cannot be easily modified by habituation (experiments 2B and 3B); and (iv) when horizontal stimuli are paired with vertical stimuli, they prefer the horizontal ones (experiments 4A and 4B).     

Expert face coding: Configural and component coding of own-race and other-race faces

Configural and holistic coding are hallmarks of face perception. Although recent studies have shown that own-race faces are coded more holistically than other-race faces, the evidence for better configural coding of own-race faces is equivocal. We directly measured configural and component coding of own- and other-race male faces in Caucasian and Chinese participants. We manipulated individual features (components) or their spatial relations (configurations) using a novel morphing method to vary difficulty parametrically and tested sensitivity to these changes in a sequential matching task. Both configural and component coding were better for upright own-race than for upright other-race faces. Inversion impaired detection of configural changes more than it did detection of component changes, but also impaired performance more for easier discriminations,independent of type of change. These results challenge explanations of face expertise that rely solely on configural and holistic processing, and also call into question the widespread interpretation of large inversion decrements as diagnostic of configural coding.     

Losing face: impaired discrimination of featural and configural information in the mouth region of an inverted face

Given that all faces share the same set of features—two eyes, a nose, and a mouth—that are arranged in similar configuration, recognition of a specific face must depend on our ability to discern subtle differences in its featural and configural properties. An enduring question in the face-processing literature is whether featural or configural information plays a larger role in the recognition process. To address this question, the face dimensions task was designed, in which the featural and configural properties in the upper (eye) and lower (mouth) regions of a face were parametrically and independently manipulated. In a same–different task, two faces were sequentially presented and tested in their upright or in their inverted orientation. Inversion disrupted the perception of featural size (Exp. 1), featural shape (Exp. 2), and configural changes in the mouth region, but it had relatively little effect on the discrimination of featural size and shape and configural differences in the eye region. Inversion had little effect on the perception of information in the top and bottom halves of houses (Exp. 3), suggesting that the lower-half impairment was specific to faces. Spatial cueing to the mouth region eliminated the inversion effect (Exp. 4), suggesting that participants have a bias to attend to the eye region of an inverted face. The collective findings from these experiments suggest that inversion does not differentially impair featural or configural face perceptions, but rather impairs the perception of information in the mouth region of the face.     

Categorical perception of face identity in noise isolates configural processing.

Neuropsychological evidence suggests that face recognition based on configural (holistic) information can occur in isolation from recognition based on local feature cues. The present study shows that configural processing can be isolated experimentally in normal subjects. A phenomenon is reported that exists only for upright whole faces, namely categorical perception (CP) of face identity in noise. Three discrimination tasks (ABX, better likeness, and similarity ratings) were used to test for perceptual distortion across the category boundary predicted from binary classification of face morphs. Noise was added such that any single local region provided unreliable cues to identity. Under these conditions, CP was found for upright faces but not for inverted faces or single features, even with more than 10,000 trials. The CP-in-noise signature phenomenon was then used to show that configural processing survives image plane rotations of 45 degrees-90 degrees.