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Face recognition requires both configural and featural processing. Configural face processing is more dependent on the right hemisphere, whereas featural face processing is more dependent on the left hemisphere. The ERP components sensitive to configural and featural face processing were found on P1 and P2, respectively. However, whether lateralized processing is independent of or interacts with the temporal sequence of configural and featural face processing is unclear. To prevent potentially confounding physical stimuli differences between configural and featural face processing from affecting the ERP components, a spatial attention paradigm was employed in which the participants were instructed to attend to the face location (the attended face condition) or the house location (the unattended face condition). The interaction effect of attention, face processing type and hemisphere on the P1 and P2 components indicates that the different mechanisms of configural and featural face processing are a function of spatial attention. Specifically, under the attended face condition, the posterior P1 (approximately 100 ms) for configural face processing was larger than that for featural face processing in the right hemisphere, whereas the P2 (approximately 220 ms) for featural face processing was larger than that for configural face processing in the left hemisphere. In contrast, under the unattended face condition, the P1 for featural face processing was larger than that for configural face processing in the left hemisphere, whereas the P2 for configural face processing was larger than that for featural face processing in the right hemisphere. Therefore, configural and featural processing involve different neural mechanisms, and more importantly, the time course of hemispheric asymmetry in configural and featural face processing is differentially modulated by spatial attention. [ABSTRACT FROM AUTHOR]

Abstract: We report data from a prosopagnosic patient (PHD), and aged-matched control participants, from experiments where participants categorised individually presented emotional faces (Experiment 1) and Thatcherised (from typical) faces (Experiment 2). In Experiment 2 participants also discriminated between simultaneously presented Thatcherised and typical faces. PHD was at chance categorising Thatcherised from typical faces. He was, however, able to discriminate between Thatcherised and typical faces, and partially able to categorise emotional faces. The results are discussed in terms of a loss of configural processing but preserved feature processing in PHD. The loss of configural processing impacts his categorisation of Thatcherised and typical faces, and his emotion processing, while his preserved feature processing supports his ability to categorise some emotional faces and his ability to discriminate between Thatcherised and typical faces. [Copyright &y& Elsevier]

Abstract: Parkinson''s disease (PD) has been frequently associated with facial emotion recognition impairments, which could adversely affect the social functioning of those patients. Facial emotion recognition requires processing of the spatial relations between facial features, known as the facial configuration. Few studies, however, have investigated this ability in people with PD. We hypothesized that facial emotion recognition impairments in patients with PD could be accounted for by a deficit in configural processing. To assess this hypothesis, three tasks were proposed to 10 patients with PD and 10 healthy controls (HC): (i) a facial emotion recognition task with upright faces, (ii) a similar task with upside-down faces, to explore the face inversion effect, and (iii) a configural task to assess participants’ abilities to detect configural modifications made on a horizontal or vertical axis. The results showed that when compared with the HC group, the PD group had impaired facial emotion recognition, in particular for faces expressing anger and fear, and exhibited reduced face inversion effect for these emotions. More importantly, the PD group''s performance on the configural task to detect vertical modifications was lower than the HC group''s. Taken together, these results suggest the presence of a configural processing alteration in patients with PD, especially for vertical, second-order information. Furthermore, configural performance was positively correlated with emotion recognition for anger, disgust, and fear, suggesting that facial emotion recognition could be related, at least partially, to configural processing. [Copyright &y& Elsevier]

Abstract: It is well documented that both featural and configural information are important in visual face recognition. Less is known, however, about the nature of the information underlying haptic face recognition and whether or not this information is the same as in vision. In our experiments we found better within modal than crossmodal face recognition performance suggesting that face representations are largely specific to each modality. Moreover, this cost in crossmodal performance was found to be independent of differences in exploratory procedures across the modalities during encoding. We found that crossmodal face perception was most efficient when configural information of the facial features was preserved suggesting that configural information is shared across modalities. Our findings suggest that face information is processed in a similar manner across vision and touch but that qualitative differences in the nature of the information encoded underlies efficient within modal relative to crossmodal recognition. [Copyright &y& Elsevier]

Abstract: Like faces, human bodies are recognized via the configuration of their parts; their recognition is impaired by inversion. Processing of configural relations has been shown to depend on perceptual expertise with certain classes of objects. Because people see their own body and others’ bodies frequently, humans are experts in the visual processing of human body postures. In addition, the observer''s own on-line, multimodal body representation which heavily relies on current proprioception may play a crucial role in recognizing human body postures. We investigated whether static body posture recognition relied on current proprioceptive inputs or whether visual familiarity and stored body representations were sufficient. IW, who is deafferented (lost cutaneous touch and proprioception from his body), was tested on the recognition of upright and inverted human body postures, faces, and houses. As controls, IW showed an inversion effect for abstract, common, and rare human body postures as well as faces, but not houses. Results rule out a strong contribution of current afferent inputs to the recognition of human postures. The findings are discussed in terms of the role of the body schema in body posture recognition and how other contributions from one''s own body may be involved in the visual processing of human bodies. [Copyright &y& Elsevier]

Human faces and bodies are environmental stimuli of special importance that the brain processes with selective attention and a highly specialized visual system. It has been shown recently that the human brain also has dedicated networks for perception of pluralities of human bodies in synchronous motion or in face-to-face interaction. Here we show that a plurality of human bodies that are merely in close spatial proximity are automatically integrated into a coherent perceptual unit. We used an EEG frequency tagging technique allowing the dissociation of the brain activity related to the component parts of an image from the activity related to the global image configuration. We presented to participants images of two silhouettes flickering at different frequencies (5.88 vs. 7.14 Hz). Clear response at these stimulation frequencies reflected response to each part of the dyad. An emerging intermodulation component (7.14 + 5.88 = 13.02 Hz), a nonlinear response regarded as an objective signature of holistic representation, was significantly enhanced in the (typical) upright relative to an (altered) inverted position. Moreover, the inversion effect was significant for the intermodulation component but not for the stimulation frequencies, suggesting a trade-off between the processing of the global dyad configuration and that of the structural properties of the dyad elements. Our results show that when presented with two humans merely in close proximity the perceptual visual system will bind them. Hence the perception of the human form might be of a fundamentally different nature when it is part of a plurality. • The human visual perceptual system involves, for plurality of conspecifics, special processing that obey to Gestalt principles.. • EEG Frequency Tagging technique can probe configural processing while dissociating the activity underlying th response to global configuration from the response to local elements forming the image.. • Individuals are perceived differently when they form a dyad: there might be a trade-off between the processing of configural properties of individual elements forming the dyad, on the one hand, and of the whole dyad structure, on the other hand. • Like faces and bodies, any plurality of individuals has a special perceptual status. [ABSTRACT FROM AUTHOR]