The perception of unfamiliar faces and houses by chimpanzees: influence of rotation angle

The inversion effect, or impaired recognition of upside-down faces, is used as evidence supporting the configural processing of faces. Human studies report a linear relationship between face-discrimination performance and orientation, such that recognition is more difficult as faces are rotated away from their typical viewpoint. Previous studies on chimpanzees also support a configural bias for processing faces, particularly faces for which subjects have developed expertise. In the present study, we examined the influence of expertise and rotation angle on the visual perception of faces in chimpanzees. Six subjects were presented with unaltered and blurred conspecific faces and houses in five orientation angles. A computerized paradigm was used to further delineate the nature of configural face processing in this species. The data were consistent with those reported in humans: chimpanzees showed a significant linear impairment when discriminating conspecific faces as they rotated away from their upright orientation. No inversion effect was observed for discriminations involving houses. Thus, chimpanzees, like humans, show a face-specific inversion effect that is linearly affected by angle of orientation, suggesting that their visual processing of faces is strongly influenced by the extraction of configural cues and closely resembles the perceptual strategies of humans.     

Effects of geometric distortions on face-recognition performance

The importance of 'configural' processing for face recognition is now well established, but it remains unclear precisely what it entails. Through four experiments we attempted to clarify the nature of configural processing by investigating the effects of various affine transformations on the recognition of familiar faces. Experiment 1 showed that recognition was markedly impaired by inversion of faces, somewhat impaired by shearing or horizontally stretching them, but unaffected by vertical stretching of faces to twice their normal height. In experiment 2 we investigated vertical and horizontal stretching in more detail, and found no effects of either transformation. Two further experiments were performed to determine whether participants were recognising stretched faces by using configural information. Experiment 3 showed that nonglobal vertical stretching of faces (stretching either the top or the bottom half while leaving the remainder undistorted) impaired recognition, implying that configural information from the stretched part of the face was influencing the process of recognition--ie that configural processing involves global facial properties. In experiment 4 we examined the effects of Gaussian blurring on recognition of undistorted and vertically stretched faces. Faces remained recognisable even when they were both stretched and blurred, implying that participants were basing their judgments on configural information from these stimuli, rather than resorting to some strategy based on local featural details. The tolerance of spatial distortions in human face recognition suggests that the configural information used as a basis for face recognition is unlikely to involve information about the absolute position of facial features relative to each other, at least not in any simple way.     

Older adults' configural processing of faces: role of second-order information

Problems with face recognition are frequent in older adults. However, the mechanisms involved have only been partially discovered. In particular, it is unknown to what extent these problems may be related to changes in configural face processing. Here, we investigated the face inversion effect (FIE) together with the ability to detect modifications in the vertical or horizontal second-order relations between facial features. We used a same/different unfamiliar face discrimination task with 33 young and 33 older adults. The results showed dissociations in the performances of older versus younger adults. There was a lack of inversion effect during the recognition of original faces by older adults. However, for modified faces, older adults showed a pattern of performance similar to that of young participants, with preserved FIE for vertically modified faces and no detectable FIE for horizontally modified faces. Most importantly, the detection of vertical modifications was preserved in older relative to young adults whereas the detection of horizontal modifications was markedly diminished. We conclude that age has dissociable effects on configural face-encoding processes, with a relative preservation of vertical compared to horizontal second-order relations processing. These results help to understand some divergent results in the literature and may explain the spared familiar face identification abilities in the daily lives of older adults.     

Face-specific capacity limits under perceptual load do not depend on holistic processing

Previous observations that face recognition may proceed automatically, without drawing on attentional resources, have been challenged by recent demonstrations that only a few faces can be processed at one time. However, a question remains about the nature of the stimulus properties that underlie face-specific capacity limits. Two experiments showed that speeded categorization of a famous face (such as a politician or pop star) is facilitated when it is congruent with a peripheral distractor face. This congruency effect is eliminated if the visual search is loaded with more than one face, unlike previous demonstrations of speeded classification using semantic information. Importantly, congruency effects are also eliminated when the search task is loaded with nontarget faces that are shown in an inverted orientation. These results indicate that face-specific capacity limits are not determined by the configural (“holistic”) properties of face recognition.     

发展性面孔失认的认知机制及其神经基础

发展性面孔失认症是指个体在童年期就开始表现出来的一种终生性面孔识别缺陷,其不能归因于智力衰退、情感障碍、物体识别困难以及后天性脑损伤.发展性面孔失认症涉及的认知机制包括面孔特异性机制、构型加工障碍、面孔探测、面孔记忆和面孔身份识别.此外,该面孔失认症的神经网络由核心神经网络和延伸的神经网络组成,前者与面孔选择反应和记忆表征有关,后者主要负责面孔知识表征、面孔长时记忆和面孔工作记忆.今后的研究应集中在完善延伸的神经网络、拓展其认知网络;进一步明确面孔探测与发展性面孔失认之间的关系;考察发展性面孔失认症的基因基础、加强其发展性研究以及推动康复工作的展开.     

面孔加工的认知神经科学研究：回顾与展望

面孔加工的认知神经科学研究中的核心问题是,是否存在功能和神经机制上独立的面孔加工模块以及面孔加工系统的组织形式。使用电生理、脑成像以及对脑损伤病人进行神经心理学检查等手段,研究者已经找到选择性地对面孔反应的脑区,即梭状回面孔区（FFA）。文章从面孔加工系统的特异性与多成分性以及面孔识别模型等方面,系统回顾了该领域的主要研究成果。文章最后还简单展望了今后的研究方向。     

Holistic processing impairment can be restricted to faces in acquired prosopagnosia: Evidence from the global/local Navon effect

Previous studies have shown that acquired prosopagnosia is characterized by impairment at holistic/configural processing. However, this view is essentially supported by studies performed with patients whose face recognition difficulties are part of a more general visual (integrative) agnosia. Here, we tested the patient PS, a case of acquired prosopagnosia whose face‐specific recognition difficulties have been related to the inability to process individual faces holistically (absence of inversion, composite, and whole–part effects with faces). Here, we show that in contrast to this impairment, the patient presents with an entirely normal response profile in a Navon hierarchical letter task: she was as fast as normal controls, faster to identify global than local letters, and her sensitivity to global interference during identification of local letters was at least as large as normal observers. These observations indicate that holistic processing as measured with global/local interference in the Navon paradigm is functionally distinct from the ability to perceive an individual face holistically.     

Can generic expertise explain special processing for faces?

Does face recognition involve face-specific cognitive and neural processes ('domain specificity') or do faces only seem special because people have had more experience of individuating them than they have of individuating members of other homogeneous object categories ('the expertise hypothesis')? Here, we summarize new data that test these hypotheses by assessing whether classic face-selective effects - holistic processing, recognition impairments in prosopagnosia and fusiform face area activation - remain face selective in comparison with objects of expertise. We argue that evidence strongly supports domain specificity rather than the expertise hypothesis. We conclude that the crucial social function of face recognition does not reflect merely a general practice phenomenon and that it might be supported by evolved mechanisms (visual or nonvisual) and/or a sensitive period in infancy.     

Individual differences in holistic processing predict face recognition ability

Why do some people recognize faces easily and others frequently make mistakes in recognizing faces? Classic behavioral work has shown that faces are processed in a distinctive holistic manner that is unlike the processing of objects. In the study reported here, we investigated whether individual differences in holistic face processing have a significant influence on face recognition. We found that the magnitude of face-specific recognition accuracy correlated with the extent to which participants processed faces holistically, as indexed by the composite-face effect and the whole-part effect. This association is due to face-specific processing in particular, not to a more general aspect of cognitive processing, such as general intelligence or global attention. This finding provides constraints on computational models of face recognition and may elucidate mechanisms underlying cognitive disorders, such as prosopagnosia and autism, that are associated with deficits in face recognition.     

Face gender recognition in developmental prosopagnosia: Evidence for holistic processing and use of configural information

Face identification deficits in developmental prosopagnosics (DPs) have been thought to be due to general difficulties with processing configural face information and integrating configural and parts information into a coherent whole (holistic processing). Gender recognition provides a further opportunity to more fully examine this issue as this ability may be intact in DPs and it has been shown to depend on processing configural information and holistic processing in neurotypical individuals. In the present study we first determined that, indeed, gender discrimination performance was similar in DPs and controls. Second, we found that inversion and scrambling (which we propose measures holistic processing and sensitivity to configural information, respectively) produced comparable deficits in DPs and controls, suggesting that both groups use holistic processing and configural information to recognize gender. This indicates that holistic processing and using configural face information are not general impairments in DP and may be more specific to face identity.     

Face recognition is affected by similarity in spatial frequency range to a greater degree than within-category object recognition

Previous studies have suggested that face identification is more sensitive to variations in spatial frequency content than object recognition, but none have compared how sensitive the 2 processes are to variations in spatial frequency overlap (SFO). The authors tested face and object matching accuracy under varying SFO conditions. Their results showed that object recognition was more robust to SFO variations than face recognition and that the vulnerability of faces was not due to reliance on configural processing. They suggest that variations in sensitivity to SFO help explain the vulnerability of face recognition to changes in image format and the lack of a middle-frequency advantage in object recognition.     

Two routes to face perception: evidence from psychophysics and computational modeling

The aim of this study was to separately analyze the role of featural and configural face representations. Stimuli containing only featural information were created by cutting the faces into their parts and scrambling them. Stimuli only containing configural information were created by blurring the faces. Employing an old-new recognition task, the aim of Experiments 1 and 2 was to investigate whether unfamiliar faces (Exp. 1) or familiar faces (Exp. 2) can be recognized if only featural or configural information is provided. Both scrambled and blurred faces could be recognized above chance level. A further aim of Experiments 1 and 2 was to investigate whether our method of creating configural and featural stimuli is valid. Pre-activation of one form of representation did not facilitate recognition of the other, neither for unfamiliar faces (Exp. 1) nor for familiar faces (Exp. 2). This indicates a high internal validity of our method for creating configural and featural face stimuli. Experiment 3 examined whether features placed in their correct categorical relational position but with distorted metrical distances facilitated recognition of unfamiliar faces. These faces were recognized no better than the scrambled faces in Experiment 1, providing further evidence that facial features are stored independently of configural information. From these results we conclude that both featural and configural information are important to recognize a face and argue for a dual-mode hypothesis of face processing. Using the psychophysical results as motivation, we propose a computational framework that implements featural and configural processing routes using an appearance-based representation based on local features and their spatial relations. In three computational experiments (Experiments 4–6) using the same sets of stimuli, we show how this framework is able to model the psychophysical data.     

Configural and component processing in simultaneous and sequential lineup procedures

Configural processing supports accurate face recognition, yet it has never been examined within the context of criminal identification lineups. We tested, using the inversion paradigm, the role of configural processing in lineups. Recent research has found that face discrimination accuracy in lineups is better in a simultaneous compared to a sequential lineup procedure. Therefore, we compared configural processing in simultaneous and sequential lineups to examine whether there are differences. We had participants view a crime video, and then they attempted to identify the perpetrator from a simultaneous or sequential lineup. The test faces were presented either upright or inverted, as previous research has shown that inverting test faces disrupts configural processing. The size of the inversion effect for faces was the same across lineup procedures, indicating that configural processing underlies face recognition in both procedures. Discrimination accuracy was comparable across lineup procedures in both the upright and inversion condition. Theoretical implications of the results are discussed.     

Famous face recognition,face matching,and extraversion

It has been previously established that extraverts who are skilled at interpersonal interaction perform significantly better than introverts on a face-specific recognition memory task. In our experiment we further investigate the relationship between extraversion and face recognition, focusing on famous face recognition and face matching. Results indicate that more extraverted individuals perform significantly better on an upright famous face recognition task and show significantly larger face inversion effects. However, our results did not find an effect of extraversion on face matching or inverted famous face recognition.     

The role of the head in configural body processing: Behavioural and electrophysiological evidence from the inversion and scrambling effect

The present study aimed to further explore the role of the head for configural body processing by comparing complete bodies with headless bodies and faceless heads (Experiment 1). A second aim was to further explore the role of the eye region in configural face processing (Experiment 2). Due to that, we conducted a second experiment with complete faces, eyeless faces, and eyes. In addition, we used two effects to manipulate configural processing: the effect of stimulus inversion and scrambling. The current data clearly show an inversion effect for intact bodies presented with head and faces including the eye region. Thus, the head and the eye region seem to be central for configural processes that are manipulated by the effect of stimulus inversion. Furthermore, the behavioural and electrophysiological body inversion effect depends on the intact configuration of bodies and is associated with the N170 as the face inversion effect depends on the intact face configuration. Hence, configural body processing depends not only on the presence of the head but rather on a complete representation of human bodies that includes the body and the head. Furthermore, configural face processing relies on intact and complete face representations that include faces and eyes.     

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.     

Unraveling mechanisms for expert object recognition: bridging brain activity and behavior

Behavioral sensitivity to object transformations and the response to novel objects (Greebles) in the fusiform face area (FFA) was measured several times during expertise training. Sensitivity to 3 transformations increased with expertise: (a) configural changes in which halves of objects were misaligned, (b) configural changes in which some of the object parts were moved, and (c) the substitution of an object part with a part from a different object. The authors found that holistic-configural effects can arise from object representations that are differentiated in terms of features or parts. Moreover, a holistic-inclusive effect was correlated with changes in the right FFA. Face recognition may not be unique in its reliance on holistic processing, measured in terms of both behavior and brain activation.     

A sideways look at configural encoding: two different effects of face rotation

Inversion has a disproportionate disruptive effect on the recognition of faces. This may be due to the disruption of holistic or configural encoding employed to recognise upright faces. The paradigm developed by Tanaka and Farah (1993 Quarterly Journal of Experimental Psychology, Section A 46 225-246) was used to investigate the effect of 90 degrees (or orthogonal) rotation on configural encoding. Faces learnt in the orthogonal condition were not recognised as well as upright faces, but a whole-face advantage was found in both cases. This whole-face advantage did not occur for inverted faces. It appears that 90 degrees rotation affects recognition but not specifically configural encoding. It is concluded that rotating a face can have at least two different effects on face processing depending on the range of rotation. Implications for the nature of facial dimensions and the expertise account of the inversion effect are considered.     

Females excel at basic face perception

Females are generally better than males at recognizing facial emotions. However, it is not entirely clear whether and in what way females may also excel at non-affective face recognition. Here, we tested males and females on two perceptual face recognition tasks that involved only neutral expressions: detection and identity discrimination. On face detection (Experiment 1), females were significantly more accurate than males in detecting upright faces. This gender difference was reduced during inverted face detection, and not present during tree detection, suggesting that the magnitude of the gender difference for performance co-varies with the extent to which face processing mechanisms are involved. On facial identity discrimination (Experiment 2), females again outperformed males, particularly when face images were masked by visual noise, or the delay between comparison face images was extended from 0.5 to 3 s. These results reveal a female advantage in processing face-specific information and underscore the role of perceptual factors in socially relevant gender differences.     

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.