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Neurofeedback training (NFT) is a promising adjuvant intervention method. The desynchronization of mu rhythm (8-13 Hz) in the electroencephalogram (EEG) over centro-parietal areas is known as a valid indicator of mirror neuron system (MNS) activation, which has been associated with social skills. Still, the effect of neurofeedback training on the MNS requires to be well investigated. The present study examined the possible impact of NFT with a mu suppression training protocol encompassing 15 NFT sessions (45 min each) on 16 healthy neurotypical participants. In separate pre- and post-training sessions, 64-channel EEG was recorded while participants (1) observed videos with various types of movements (including complex goal-directed hand movements and social interaction scenes) and (2) performed the "Reading the Mind in the Eyes Test" (RMET). EEG source reconstruction analysis revealed statistically significant mu suppression during hand movement observation across MNS-attributed fronto-parietal areas after NFT. The frequency analysis showed no significant mu suppression after NFT, despite the fact that numerical mu suppression appeared to be visible in a majority of participants during goal-directed hand movement observation. At the behavioral level, RMET accuracy scores did not suggest an effect of NFT on the ability to interpret subtle emotional expressions, although RMET response times were reduced after NFT. In conclusion, the present study exhibited preliminary and partial evidence that mu suppression NFT can induce mu suppression in MNS-attributed areas. More powerful experimental designs and longer training may be necessary to induce substantial and consistent mu suppression, particularly while observing social scenarios., (© 2024. The Author(s).)

The brain calibrates itself based on the past stimulus diet, which makes frequently observed stimuli appear as typical (as opposed to uncommon stimuli, which appear as distinctive). Based on predictive processing theory, the brain should be more "prepared" for typical exemplars, because these contain information that has been encountered frequently, allowing it to economically represent items of that category. Thus, one could ask whether predictability and typicality of visual stimuli interact, or rather act in an additive manner. We adapted the design by Egner and colleagues (2010), who used cues to induce expectations about stimulus category (face vs. chair) occurrence during an orthogonal inversion detection task. We measured BOLD responses with fMRI in 35 participants. First, distinctive stimuli always elicited stronger responses than typical ones in all ROIs, and our whole-brain directional contrasts for the effects of typicality and distinctiveness converge with previous findings. Second and importantly, we could not replicate the interaction between category and predictability reported by Egner et al. (2010), which casts doubt on whether cueing designs are ideal to elicit reliable predictability effects. Third, likely as a consequence of the lack of predictability effects, we found no interaction between predictability and typicality in any of the four tested regions (bilateral fusiform face areas, lateral occipital complexes) when considering both categories, nor in the whole brain. We discuss the issue of replicability in neuroscience and sketch an agenda for how future studies might address the same question., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Ficco et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Valentine's influential norm-based multidimensional face-space model (nMDFS) predicts that perceived distinctiveness of a face increases with its distance to the norm. Occipito-temporal event-related potentials (ERPs) have been recently shown to respond selectively to variations in distance-to-norm (P200) or familiarity (N250, late negativity), respectively (Wuttke & Schweinberger, 2019). Despite growing evidence on interindividual differences in face perception skills at the behavioral level, little research has focused on their electrophysiological correlates. To reveal potential interindividual differences in face spaces, we contrasted high and low performers in face recognition in regards to distance-to-norm (P200) and familiarity (N250). We replicated both the P200 distance-to-norm and the N250 familiarity effect. Importantly, we observed: i) reduced responses in low compared to high performers of face recognition, especially in terms of smaller distance-to-norm effects in the P200, possibly indicating less 'expanded' face spaces in low compared to high performers; ii) increased N250 responses to familiar original faces in high performers, suggesting more robust face identity representations. In summary, these findings suggest the contribution of both early norm-based face coding and robust face representations to individual face recognition skills, and indicate that ERPs can offer a promising route to understand individual differences in face perception and their neurocognitive correlates., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Two competing theories explain the other-'race' effect (ORE) either by greater perceptual expertise to same-'race' (SR) faces or by social categorization of other-'race' (OR) faces at the expense of individuation. To assess expertise and categorization contributions to the ORE, a promising-yet overlooked-approach is comparing activations for different other-'races'. We present a label-based systematic review of neuroimaging studies reporting increased activity in response to OR faces (African, Caucasian, or Asian) when compared with the SR of participants. Hypothetically, while common activations would reflect general aspects of OR perception, 'race'-preferential ones would represent effects of 'race'-specific visual appearance. We find that several studies report activation of occipito-temporal and midcingulate areas in response to faces across different other-'races', presumably due to high demand on the visual system and category processing. Another area reported in response to all OR faces, the caudate nucleus, suggests the involvement of socio-affective processes and behavioural regulation. Overall, our results support hybrid models-both expertise and social categorization contribute to the ORE, but they provide little evidence for reduced motivation to process OR faces. Additionally, we identify areas preferentially responding to specific OR faces, reflecting effects of visual appearance., (© 2022 The Authors. British Journal of Psychology published by John Wiley & Sons Ltd on behalf of The British Psychological Society.)

Recognizing people from their voices may be facilitated by a voice's distinctiveness, in a manner similar to that which has been reported for faces. However, little is known about the neural time-course of voice learning and the role of facial information in voice learning. Based on evidence for audiovisual integration in the recognition of familiar people, we studied the behavioral and electrophysiological correlates of voice learning associated with distinctive or non-distinctive faces. We repeated twelve unfamiliar voices uttering short sentences, together with either distinctive or non-distinctive faces (depicted before and during voice presentation) in six learning-test cycles. During learning, distinctive faces increased early visually-evoked (N170, P200, N250) potentials relative to non-distinctive faces, and face distinctiveness modulated voice-elicited slow EEG activity at the occipito-temporal and fronto-central electrodes. At the test, unimodally-presented voices previously learned with distinctive faces were classified more quickly than were voices learned with non-distinctive faces, and also more quickly than novel voices. Moreover, voices previously learned with faces elicited an N250-like component that was similar in topography to that typically observed for facial stimuli. The preliminary source localization of this voice-induced N250 was compatible with a source in the fusiform gyrus. Taken together, our findings provide support for a theory of early interaction between voice and face processing areas during both learning and voice recognition.

Most findings on prosopagnosia to date suggest preserved voice recognition in prosopagnosia (except in cases with bilateral lesions). Here we report a follow-up examination on M.T., suffering from acquired prosopagnosia following a large unilateral right-hemispheric lesion in frontal, parietal, and anterior temporal areas excluding core ventral occipitotemporal face areas. Twenty-three years after initial testing we reassessed face and object recognition skills [Henke, K., Schweinberger, S. R., Grigo, A., Klos, T., & Sommer, W. (1998). Specificity of face recognition: Recognition of exemplars of non-face objects in prosopagnosia. Cortex , 34 (2), 289-296]; [Schweinberger, S. R., Klos, T., & Sommer, W. (1995). Covert face recognition in prosopagnosia - A dissociable function? Cortex , 31 (3), 517-529] and additionally studied voice recognition. Confirming the persistence of deficits, M.T. exhibited substantial impairments in famous face recognition and memory for learned faces, but preserved face matching and object recognition skills. Critically, he showed substantially impaired voice recognition skills. These findings are congruent with the ideas that (i) prosopagnosia after right anterior temporal lesions can persist over long periods > 20 years, and that (ii) such lesions can be associated with both facial and vocal deficits in person recognition.

Recent research suggested disproportional usage of shape information by people with poor face recognition, although texture information appears to be more important for familiar face recognition. Here, we tested a training program with faces that were selectively caricatured in either shape or texture parameters. Forty-eight young adults with poor face recognition skills (1 SD below the mean in at least 2/3 face processing tests: CFMT, GFMT, BFFT) were pseudo-randomly assigned to either one of two training groups or a control group (n = 16 each). Training comprised six sessions over three weeks. Per session, participants studied ten unfamiliar facial identities whose shape or texture characteristics were caricatured. Before and after training (or waiting in the control group), all participants completed EEG experiments on face learning and famous face recognition, and behavioral face processing tests. Results showed small but specific training-induced improvements: Whereas shape training improved face matching (training tasks, and to some extent GFMT), texture training elicited marked improvements in face learning (CFMT). Moreover, for the texture training group the N170 ERP was enhanced for novel faces post-training, suggesting training-induced changes in early markers of face processing. Although further research is necessary, this suggests that parameter-specific caricature training is a promising way to improve performance in people with poor face recognition skills., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Modifying established motor skills is a challenging endeavor due to proactive interference from undesired old to desired new actions, calling for high levels of cognitive control. Motor restrictions may facilitate the modification of motor skills by rendering undesired responses physically impossible, thus reducing demands to response inhibition. Here we studied behavioral and EEG effects of rule changes to typing in skilled touch-typists. The respective rule change-typing without using the left index finger-was either implemented per instruction only or with an additional motor restriction. In both groups, the rule change elicited delays and more errors in typing, indicating the occurrence of proactive interference. While stimulus-locked ERPs did not exhibit prominent effects of rule change or group, response-locked ERPs revealed that the time courses of preparatory brain activity preceding typing responses depended on the presence of motor restriction. Although further research is necessary to corroborate our findings, they indicate a novel brain correlate that represents changes in inhibitory response preparation induced by short-term motor restrictions., (© 2021. The Author(s).)

Although the other-race effect (ORE; superior recognition of own- relative to other-race faces) is well established, the mechanisms underlying it are not well understood. We examined whether the ORE is attributable to differential use of shape and texture cues for own- vs. other-race faces. Shape cues are particularly important for detecting that an own-race face is unfamiliar, whereas texture cues are more important for recognizing familiar and newly learned own-race faces. We compared the influence of shape and texture cues on Caucasian participants' recognition of Caucasian and East Asian faces using two complementary approaches. In Experiment 1, participants studied veridical, shape-caricatured, or texture-caricatured faces and then were asked to recognize them in an old/new recognition task. In Experiment 2, all study faces were veridical and we independently removed the diagnosticity of shape (or texture) cues in the test phase by replacing original shape (or texture) with average shape (or texture). Despite an overall own-race advantage, participants' use of shape and texture cues was comparable for own- and other-race faces. These results suggest that the other-race effect is not attributable to qualitative differences in the use of shape and texture cues., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Changing pre-existing, automatized motor skills often requires interference control. Prepotent response inhibition - one subdimension of inhibition - has been theorized to be particularly associated with successful interference control in motor skills. Recent evidence suggests that different inhibition subdimensions elicit distinct ERP patterns (with larger P3 components for response inhibition). Therefore, we examined whether a similar ERP pattern would arise in a task demanding participants to overcome interference emerging from strong motor automatisms. This was realized within a typing paradigm involving a letter switch manipulation which is able to produce strong, immediate interference effects. Most importantly, stimulus-locked ERP analyses revealed an enhanced P3 component at frontal, central and most pronouncedly parietal sites for interference trials, in line with previous reported patterns for response inhibition. Together, different analyses provide first insights into the electrophysiological correlates of motor skill change, corroborating the pivotal role of response inhibition for successful interference control., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: Body dysmorphic disorder (BDD) is characterized by an excessive preoccupation with one or more perceived flaws in one's own appearance. Previous studies provided evidence for deficits in configural and holistic processing in BDD. Preliminary evidence suggests abnormalities at an early stage of visual processing. The present study is the first examining early neurocognitive perception of the own face in BDD by using electroencephalography (EEG). We investigated the face inversion effect, in which inverted (upside-down) faces are disproportionately poorly processed compared to upright faces. This effect reflects a disruption of configural and holistic processing, and in consequence a preponderance of featural face processing., Methods: We recorded face-sensitive event-related potentials (ERPs) in 16 BDD patients and 16 healthy controls, all unmedicated. Participants viewed upright and inverted (upside-down) images of their own face and an unfamiliar other face, each in two facial emotional expressions (neutral vs. smiling). We calculated the early ERP components P100, N170, P200, N250, and the late positive component (LPC), and compared amplitudes among both groups., Results: In the early P100, no face inversion effects were found in both groups. In the N170, both groups exhibited the common face inversion effects, with significantly larger N170 amplitudes for inverted than upright faces. In the P200, both groups exhibited larger inversion effects to other (relative to own) faces, with larger P200 amplitudes for other upright than inverted faces. In the N250, no significant group differences were found in face processing. In the LPC, both groups exhibited larger inversion effects to other (relative to own) faces, with larger LPC amplitudes for other inverted than upright faces. These overall patterns appeared to be comparable for both groups. Smaller inversion effects to own (relative to other) faces were observed in none of these components in BDD, relative to controls., Conclusions: The findings suggest no evidence for abnormalities at all levels of early face processing in our observed sample of BDD patients. Further research should investigate the neural substrates underlying BDD symptomatology., (Copyright © 2020 Ritter, Kaufmann, Krahmer, Wiese, Stangier and Schweinberger.)

A common cognitive problem reported by older people is compromised face recognition, which is often paralleled by age-related changes in face-sensitive and memory-related components in event-related brain potentials (ERPs). We developed a new training using photorealistic caricatures based on evidence that caricatures are beneficial for people with compromised face processing. Twenty-four older participants (62-75 yrs, 13 female) completed 12 training sessions (3 per week, 60 min each) and 24 older participants (61-76 yrs, 12 female) acted as controls. Before and after training (or waiting), participants took part in a diagnostic test battery for face processing abilities, and in ERP experiments on face learning and recognition. Although performance improvements during the training provided little evidence for generalization to other face processing tasks, ERPs showed substantial training-related enhancements of face-sensitive ERPs. Specifically, we observed marked increases of the N170, P200 and N250 components, which may indicate training-induced enhancement of face detection and activation of identity-specific representations. Thus, neuronal correlates of face processing are plastic in older age, and can be modulated by caricature training., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Seeing a face being touched in spatial and temporal synchrony with the own face produces a bias in self-recognition, whereby the other face becomes more likely to be perceived as the self. The present study employed event-related potentials to explore whether this enfacement effect reflects initial face encoding, enhanced distinctiveness of the enfaced face, modified self-identity representations, or even later processing stages that are associated with the emotional processing of faces. Participants were stroked in synchrony or asynchrony with an unfamiliar face they observed on a monitor in front of them, in a situation approximating a mirror image. Subsequently, event-related potentials were recorded during the presentation of (a) a previously synchronously stimulated face, (b) an asynchronously stimulated face, (c) observers' own face, (d) filler faces, and (e) a to-be-detected target face, which required a response. Observers reported a consistent enfacement illusion after synchronous stimulation. Importantly, the synchronously stimulated face elicited more prominent N170 and P200 responses than the asynchronously stimulated face. By contrast, similar N250 and P300 responses were observed in these conditions. These results suggest that enfacement modulates early neural correlates of face encoding and facial prototypicality, rather than identity self-representations and associated emotional processes., (© 2018 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

The role of second-order configuration-that is, metric distances between individual features-for familiar face recognition has been the subject of debate. Recent reports suggest that better face recognition abilities coincide with a weaker reliance on shape information for face recognition. We examined contributions of second-order configuration to familiar face repetition priming by manipulating metric distances between facial features. S1 comprised familiar face primes as either: unaltered, with increased or decreased interocular distance, with increased or decreased distance between nose and mouth; or a different familiar face (unprimed). Participants performed a familiarity decision task on familiar and unfamiliar S2 targets, and completed a test battery consisting of three face identity processing tests. Accuracies, reaction times, and inverse efficiency scores were assessed for the priming experiment, and potential priming costs in inverse efficiency scores were correlated with test battery scores. Overall, priming was found, and priming effects were reduced only by primes with interocular distance distortions. Correlational data showed that better face recognition skills coincided with a weaker reliance on second-order configurations. Our findings (a) suggest an importance of interocular, but not mouth-to-nose, distances for familiar face recognition and (b) show that good face recognizers are less sensitive to second-order configuration.

For face recognition, observers utilize both shape and texture information. Here, we investigated the relative diagnosticity of shape and texture for delayed matching of familiar and unfamiliar faces (Experiment 1) and identifying familiar and newly learned faces (Experiment 2). Within each familiarity condition, pairs of 3D-captured faces were morphed selectively in either shape or texture in 20% steps, holding the respective other dimension constant. We also assessed participants' individual face-processing skills via the Bielefelder Famous Faces Test (BFFT), the Glasgow Face Matching Test, and the Cambridge Face Memory Test (CFMT). Using multilevel model analyses, we examined probabilities of same versus different responses (Experiment 1) and of original identity versus other/unknown identity responses (Experiment 2). Overall, texture was more diagnostic than shape for both delayed matching and identification, particularly so for familiar faces. On top of these overall effects, above-average BFFT performance was associated with enhanced utilization of texture in both experiments. Furthermore, above-average CFMT performance coincided with slightly reduced texture dominance in the delayed matching task (Experiment 1) and stronger sensitivity to morph-based changes overall, that is irrespective of morph type, in the face identification task (Experiment 2). Our findings (1) show the disproportionate importance of texture information for processing familiar face identity and (2) provide further evidence that familiar and unfamiliar face identity perception are mediated by different underlying processes., (© 2016 The British Psychological Society.)

Recent findings show benefits for learning and subsequent recognition of faces caricatured in shape or texture, but there is little evidence on whether this caricature learning advantage generalizes to recognition of veridical counterparts at test. Moreover, it has been reported that there is a relatively higher contribution of texture information, at the expense of shape information, for familiar compared to unfamiliar face recognition. The aim of this study was to examine whether veridical faces are recognized better when they were learned as caricatures compared to when they were learned as veridicals-what we call a caricature generalization benefit. Photorealistic facial stimuli derived from a 3-D camera system were caricatured selectively in either shape or texture by 50 %. Faces were learned across different images either as veridicals, shape caricatures, or texture caricatures. At test, all learned and novel faces were presented as previously unseen frontal veridicals, and participants performed an old-new task. We assessed accuracies, reaction times, and face-sensitive event-related potentials (ERPs). Faces learned as caricatures were recognized more accurately than faces learned as veridicals. At learning, N250 and LPC were largest for shape caricatures, suggesting encoding advantages of distinctive facial shape. At test, LPC was largest for faces that had been learned as texture caricatures, indicating the importance of texture for familiar face recognition. Overall, our findings demonstrate that caricature learning advantages can generalize to and, importantly, improve recognition of veridical versions of faces.

According to the norm-based version of the multidimensional face space model (nMDFS, Valentine, 1991), any given face and its corresponding anti-face (which deviates from the norm in exactly opposite direction as the original face) should be equidistant to a hypothetical prototype face (norm), such that by definition face and anti-face should bear the same level of perceived typicality. However, it has been argued that familiarity affects perceived typicality and that representations of familiar faces are qualitatively different (e.g., more robust and image-independent) from those for unfamiliar faces. Here we investigated the role of face familiarity for rated typicality, using two frequently used operationalisations of typicality (deviation-based: DEV), and distinctiveness (face in the crowd: FITC) for faces of celebrities and their corresponding anti-faces. We further assessed attractiveness, likeability and trustworthiness ratings of the stimuli, which are potentially related to typicality. For unfamiliar faces and their corresponding anti-faces, in line with the predictions of the nMDFS, our results demonstrate comparable levels of perceived typicality (DEV). In contrast, familiar faces were perceived much less typical than their anti-faces. Furthermore, familiar faces were rated higher than their anti-faces in distinctiveness, attractiveness, likability and trustworthiness. These findings suggest that familiarity strongly affects the distribution of facial representations in norm-based face space. Overall, our study suggests (1) that familiarity needs to be considered in studies of mental representations of faces, and (2) that familiarity, general distance-to-norm and more specific vector directions in face space make different and interactive contributions to different types of facial evaluations.

Recent evidence suggests that while reflectance information (including color) may be more diagnostic for familiar face recognition, shape may be more diagnostic for unfamiliar face identity processing. Moreover, event-related potential (ERP) findings suggest an earlier onset for neural processing of facial shape compared to reflectance. In the current study, we aimed to explore specifically the roles of facial shape and color in a familiarity decision task using pre-experimentally familiar (famous) and unfamiliar faces that were caricatured either in shape-only, color-only, or both (full; shape + color) by 15%, 30%, or 45%. We recorded accuracies, mean reaction times, and face-sensitive ERPs. Performance data revealed that shape caricaturing facilitated identity processing for unfamiliar faces only. In the ERP data, such effects of shape caricaturing emerged earlier than those of color caricaturing. Unsurprisingly, ERP effects were accentuated for larger levels of caricaturing. Overall, our findings corroborate the importance of shape for identity processing of unfamiliar faces and demonstrate an earlier onset of neural processing for facial shape compared to color.

Increased early negativity to repeated faces over inferior temporal regions around 200-300 ms has been related to the reactivation of mental representations of individual identities of familiar faces. Since this modulation is larger for same-image (compared to different-image) repetitions of a familiar face, it is debated whether it reflects physical stimulus similarity between prime and target, or reactivation of perceived representations of identity. In Experiment 1 participants performed a four-choice identification task on famous target faces, which were always preceded by the same average face. This average face served as prime stimulus. Crucially, by adapting participants to specific anti-faces, we induced different illusory facial identities (cf. Leopold, D.A., O'Toole, A.J., Vetter, T., Blanz, V., 2001. Prototype-referenced shape encoding revealed by high-level after effects. Nature Neuroscience 4 (1), 89-94) in the same physical prime. Importantly, temporal ERPs (~ 155-235 ms) were significantly more negative for "Primed" than for "Unprimed" trials. In Experiment 2, we determined whether this effect was due to the encoding of shape information, by using anti-shape adaptors with constant average reflectance information. Priming by these anti-shape adapted average primes did not elicit a similar temporal ERP modulation. We conclude that these early temporal ERP modulations evoked by a combination of anti-face adaptation and immediate-repetition priming represent a neural correlate of the activation of mental representations of individual familiar faces. These identity specific representations can be triggered even by physically identical prime stimuli, when preceded by corresponding anti-face adaptation., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Face recognition is a remarkable human ability, which underlies a great deal of people's social behavior. Individuals can recognize family members, friends, and acquaintances over a very large range of conditions, and yet the processes by which they do this remain poorly understood, despite decades of research. Although a detailed understanding remains elusive, face recognition is widely thought to rely on configural processing, specifically an analysis of spatial relations between facial features (so-called second-order configurations). In this article, we challenge this traditional view, raising four problems: (1) configural theories are underspecified; (2) large configural changes leave recognition unharmed; (3) recognition is harmed by nonconfigural changes; and (4) in separate analyses of face shape and face texture, identification tends to be dominated by texture. We review evidence from a variety of sources and suggest that failure to acknowledge the impact of familiarity on facial representations may have led to an overgeneralization of the configural account. We argue instead that second-order configural information is remarkably unimportant for familiar face recognition., (© The Author(s) 2015.)

Spatially caricatured faces were recently shown to benefit face learning (Schulz et al., 2012a). Moreover, spatial information may be particularly important for encoding unfamiliar faces, but less so for recognizing familiar faces (Kaufmann et al., 2013). To directly test the possibility of a major role of reflectance information for the recognition of familiar faces, we compared effects of selective photorealistic caricaturing in either shape or reflectance on face learning and recognition. Participants learned 3D-photographed faces across different viewpoints, and different images were presented at learning and test. At test, performance benefits for both types of caricatures were modulated by familiarity: Benefits for learned faces were substantially larger for reflectance caricatures, whereas benefits for novel faces were numerically larger for shape caricatures. ERPs confirmed a consistent reduction of the occipitotemporal P200 (200-240 ms) by shape caricaturing, whereas the most prominent effect of reflectance caricaturing was seen in an enhanced posterior N250 (240-400 ms), a component that has been related to the activation of acquired face representations. Our results suggest that performance benefits for face learning caused by distinctive spatial versus reflectance information are mediated by different neural processes with different timing and support a prominent role of reflectance for the recognition of learned faces., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Participants are more accurate at remembering faces of their own relative to another ethnic group (own-race bias, ORB). This phenomenon has been explained by reduced perceptual expertise, or alternatively, by the categorization of other-race faces into social out-groups and reduced effort to individuate such faces. We examined event-related potential (ERP) correlates of the ORB, testing recognition memory for Asian and Caucasian faces in Caucasian and Asian participants. Both groups demonstrated a significant ORB in recognition memory. ERPs revealed more negative N170 amplitudes for other-race faces in both groups, probably reflecting more effortful structural encoding. Importantly, the ethnicity effect in left-hemispheric N170 during learning correlated significantly with the behavioral ORB. Similarly, in the subsequent N250, both groups demonstrated more negative amplitudes for other-race faces, and during test phases, this effect correlated significantly with the ORB. We suggest that ethnicity effects in the N170 reflect an early categorization of other-race faces into a social out-group, resulting in less efficient encoding and thus decreased memory. Moreover, ethnicity effects in the N250 may represent the "tagging" of other-race faces as perceptually salient, which hampers the recognition of these faces.

Aftereffects of adaptation have revealed both independent and interactive coding of facial signals including identity and expression or gender and age. By contrast, interactive processing of non-linguistic features in voices has rarely been investigated. Here we studied bidirectional cross-categorical aftereffects of adaptation to vocal age and gender. Prolonged exposure to young (~20yrs) or old (~70yrs) male or female voices biased perception of subsequent test voices away from the adapting age (Exp. 1) and the adapting gender (Exp. 2). Relative to gender-congruent adaptor-test pairings, vocal age aftereffects (VAAEs) were reduced but remained significant when voice gender changed between adaptation and test. This suggests that the VAAE relies on both gender-specific and gender-independent age representations for male and female voices. By contrast, voice gender aftereffects (VGAEs) were not modulated by age-congruency of adaptor and test voices (Exp. 2). Instead, young voice adaptors generally induced larger VGAEs than old voice adaptors. This suggests that young voices are particularly efficient gender adaptors, likely reflecting more pronounced sexual dimorphism in these voices. In sum, our findings demonstrate how high-level processing of vocal age and gender is partially intertwined., (© 2013.)

Previous findings demonstrated that increasing facial distinctiveness by means of spatial caricaturing improves face learning and results in modulations of event-related-potential (ERP) components associated with the processing of typical shape information (P200) and with face learning and recognition (N250). The current study investigated performance-based differences in the effects of spatial caricaturing: a modified version of the Bielefelder famous faces test (BFFT) was applied to subdivide a non-clinical group of 28 participants into better and worse face recognizers. Overall, a learning benefit was seen for caricatured compared to veridical faces. In addition, for learned faces we found larger caricaturing effects in response times, inverse efficiency scores as well as in P200 and N250 amplitudes in worse face recognizers, indicating that these individuals profited disproportionately from exaggerated idiosyncratic face shape. During learning and for novel faces at test, better and worse recognizers showed similar caricaturing effects. We suggest that spatial caricaturing helps better and worse face recognizers accessing critical idiosyncratic shape information that supports identity processing and learning of unfamiliar faces. For familiarized faces, better face recognizers might depend less on exaggerated shape and make better use of texture information than worse recognizers. These results shed light on the transition from unfamiliar to familiar face processing and may also be relevant for developing training-programmes for people with difficulties in face recognition., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Distinctive faces are easier to learn and recognise than typical faces. We investigated effects of natural vs. artificial distinctiveness on performance and neural correlates of face learning. Spatial caricatures of initially non-distinctive faces were created such that their rated distinctiveness matched a set of naturally distinctive faces. During learning, we presented naturally distinctive, caricatured, and non-distinctive faces for later recognition among novel faces, using different images of the same identities at learning and test. For learned faces, an advantage in performance was observed for naturally distinctive and caricatured over non-distinctive faces, with larger benefits for naturally distinctive faces. Distinctive and caricatured faces elicited more negative occipitotemporal ERPs (P200, N250) and larger centroparietal positivity (LPC) during learning. At test, earliest distinctiveness effects were again seen in the P200. In line with recent research, N250 and LPC were larger for learned than for novel faces overall. Importantly, whereas left hemispheric N250 was increased for learned naturally distinctive faces, right hemispheric N250 responded particularly to caricatured novel faces. We conclude that natural distinctiveness induces benefits to face recognition beyond those induced by exaggeration of a face's idiosyncratic shape, and that the left hemisphere in particular may mediate recognition across different images., (Copyright © 2012 Elsevier Inc. All rights reserved.)

To assess the role of shape information for unfamiliar face learning, we investigated effects of photorealistic spatial anticaricaturing and caricaturing on later face recognition. We assessed behavioural performance and event-related brain potential (ERP) correlates of recognition, using different images of anticaricatures, veridical faces, or caricatures at learning and test. Relative to veridical faces, recognition performance improved for caricatures, with performance decrements for anticaricatures in response times. During learning, an amplitude pattern with caricatures>veridicals=anticaricatures was seen for N170, left-hemispheric ERP negativity during the P200 and N250 time segments (200-380 ms), and for a late positive component (LPC, 430-830 ms), whereas P200 and N250 responses exhibited an additional difference between veridicals and anticaricatures over the right hemisphere. During recognition, larger amplitudes for caricatures again started in the N170, whereas the P200 and the right-hemispheric N250 exhibited a more graded pattern of amplitude effects (caricatures>veridicals>anticaricatures), a result which was specific to learned but not novel faces in the N250. Together, the results (i) emphasise the role of facial shape for visual encoding in the learning of previously unfamiliar faces and (ii) provide important information about the neuronal timing of the encoding advantage enjoyed by faces with distinctive shape., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

We report two experiments on the influence of spatial caricaturing on face learning and recognition. In the learning phase of Experiment 1, participants learned unfamiliar faces, half of which were caricatured at an exaggeration level of 30%. During learning we found increased N170, N250 and LPC and decreased P200 for caricatures. At test we observed better generalization to non-identical exemplars for faces learned as caricatures. At test, N250 was larger for caricatures. In Experiment 2, using more and stronger levels of caricaturing (0%=veridical, 35% and 70%), we replicated and extended main findings of Experiment 1 and found a clear learning advantage for caricatures. ERP and performance effects were directly related to the level of caricaturing. Overall, the present results suggest that (i) distinctive shape information is particularly informative to form new face representations for unfamiliar faces, and (ii) this formation of new representations is reflected by an increase in occipito-temporal negativity that is most prominent in the time range of the P200 and N250 components., (Copyright © 2011 Elsevier B.V. All rights reserved.)

We investigated the influence of Fourier power spectrum (1/f(p)) characteristics on face learning while recording ERPs that are associated with the representation of faces. Two image sets with an altered 1/f(p) characteristics were created. The first set consisted of stimuli with a STEEP SLOPE (1/f(3.5)) and therefore enhanced low spatial frequencies (LSF) and attenuated high spatial frequencies (HSF). The second set consisted of stimuli with a SHALLOW SLOPE (1/f(2)), similar to complex natural scenes and artwork, resulting in enhanced HSF and attenuated LSF. Faces with a SHALLOW SLOPE elicited larger N170 and N250 amplitudes and larger old/new effects for central positivity in comparison to unmodified faces. The opposite effect was observed for faces with a STEEP SLOPE that led to slower reaction times. This result suggests that diminishing the ratio of fine detail (HSF) to coarse structures (LSF) impairs face learning, whereas increasing it facilitates neurocognitive correlates of face learning., (Copyright © 2011 Elsevier B.V. All rights reserved.)

While high-level adaptation to faces has been extensively investigated, research on behavioural and neural correlates of auditory adaptation to paralinguistic social information in voices has been largely neglected. Here we replicate novel findings that adaptation to voice gender causes systematic contrastive aftereffects such that repeated exposure to female voice adaptors causes a subsequent test voice to be perceived as more male (and vice versa), even minutes after adaptation [S.R. Schweinberger et al., (2008), Current Biology, 18, 684-688). In addition, we recorded event-related potentials to test-voices morphed along a gender continuum. An attenuation in frontocentral N1-P2 amplitudes was seen when a test voice was preceded by gender-congruent voice adaptors. Additionally, similar amplitude attenuations were seen in a late parietal positive component (P3, 300-700 ms). These findings suggest that contrastive coding of voice gender takes place within the first few hundred milliseconds from voice onset, and is implemented by neurons in auditory areas that are specialised for detecting male and female voice quality.

We used ERPs to investigate neural correlates of face learning. At learning, participants viewed video clips of unfamiliar people, which were presented either with or without voices providing semantic information. In a subsequent face-recognition task (four trial blocks), learned faces were repeated once per block and presented interspersed with novel faces. To disentangle face from image learning, we used different images for face repetitions. Block effects demonstrated that engaging in the face-recognition task modulated ERPs between 170 and 900 msec poststimulus onset for learned and novel faces. In addition, multiple repetitions of different exemplars of learned faces elicited an increased bilateral N250. Source localizations of this N250 for learned faces suggested activity in fusiform gyrus, similar to that found previously for N250r in repetition priming paradigms [Schweinberger, S. R., Pickering, E. C., Jentzsch, I., Burton, A. M., & Kaufmann, J. M. Event-related brain potential evidence for a response of inferior temporal cortex to familiar face repetitions. Cognitive Brain Research, 14, 398-409, 2002]. Multiple repetitions of learned faces also elicited increased central-parietal positivity between 400 and 600 msec and caused a bilateral increase of inferior-temporal negativity (>300 msec) compared with novel faces. Semantic information at learning enhanced recognition rates. Faces that had been learned with semantic information elicited somewhat less negative amplitudes between 700 and 900 msec over left inferior-temporal sites. Overall, the findings demonstrate a role of the temporal N250 ERP in the acquisition of new face representations across different images. They also suggest that, compared with visual presentation alone, additional semantic information at learning facilitates postperceptual processing in recognition but does not facilitate perceptual analysis of learned faces.

We report two experiments in which participants classified familiarity and rated best-likeness of photorealistic spatial caricatures and anti-caricatures (up to a distortion level of 30%) in comparison to veridical pictures of famous faces (Experiment 1) and personally familiar faces (Experiment 2). In both experiments there was no evidence for a caricature advantage in the behavioural data. In line with previous research, caricatures were perceived as worse likenesses than veridical pictures and moderate anti-caricatures. In Experiment 2, ERPs for familiar faces were largely unaffected by spatial caricaturing, whereas clear effects of caricaturing were observed for unfamiliar faces, for which caricaturing elicited increased occipito-temporal N170 and N250 responses. Whereas increases in N170 amplitude were limited to the first half of the experiment, increases in N250 were largest after a number of stimulus repetitions in the second half of the experiment. In the second half, ERPs to caricatured unfamiliar faces became more similar to ERPs to familiar faces, whereas ERP differences between familiar and unfamiliar faces remained prominent for veridicals and anti-caricatures. In the context of previous reports of caricature effects for line-drawings, these results imply that non-spatial (e.g., texture) information plays a prominent role for familiar face recognition, whereas spatial caricaturing may be particularly important for the recognition of unfamiliar faces, by increasing their distinctiveness.

Perceptual aftereffects following adaptation to simple stimulus attributes (e.g., motion, color) have been studied for hundreds of years. A striking recent discovery was that adaptation also elicits contrastive aftereffects in visual perception of complex stimuli and faces [1-6]. Here, we show for the first time that adaptation to nonlinguistic information in voices elicits systematic auditory aftereffects. Prior adaptation to male voices causes a voice to be perceived as more female (and vice versa), and these auditory aftereffects were measurable even minutes after adaptation. By contrast, crossmodal adaptation effects were absent, both when male or female first names and when silently articulating male or female faces were used as adaptors. When sinusoidal tones (with frequencies matched to male and female voice fundamental frequencies) were used as adaptors, no aftereffects on voice perception were observed. This excludes explanations for the voice aftereffect in terms of both pitch adaptation and postperceptual adaptation to gender concepts and suggests that contrastive voice-coding mechanisms may routinely influence voice perception. The role of adaptation in calibrating properties of high-level voice representations indicates that adaptation is not confined to vision but is a ubiquitous mechanism in the perception of nonlinguistic social information from both faces and voices.

Recent studies have identified a prominent face-selective ERP response to immediate repetitions of faces approximately 250 ms (N250r) which was strongly attenuated or eliminated for control stimuli (Schweinberger, Huddy, and Burton 2004, NeuroReport, 15, 1501-1505). In the present study we used a 148-channel whole head neuromagnetometer to investigate event-related magnetic fields (ERMFs) elicited by repetitions of exemplars of human faces, inverted human faces, primate faces, and car fronts. Participants counted rare pictures of butterflies interspersed in a series of pairs of one of these categories. The second stimulus of each pair could either be a repetition or a non-repetition of the first stimulus. We observed prominent M100 (90-140 ms) and M170 (140-220 ms) responses. Both M100 and M170 were insensitive to repetition and showed little differences between stimulus categories, except for a slight increase and delay of M170 to inverted faces. By contrast, we observed a repetition-sensitive M250r response (220-330 ms). This M250r was larger for upright human and primate faces when compared to both inverted human faces and cars, a finding that was specific for right hemispheric sensors. Source localization suggested different generators for M170 and M250r in occipitotemporal and fusiform areas, respectively. These findings suggest that repetition-sensitive brain activity approximately 250 ms reflects the transient activation of object representations, with largest responses for upright faces, in the right hemisphere.

While audiovisual integration is well known in speech perception, faces and speech are also informative with respect to speaker recognition. To date, audiovisual integration in the recognition of familiar people has never been demonstrated. Here we show systematic benefits and costs for the recognition of familiar voices when these are combined with time-synchronized articulating faces, of corresponding or noncorresponding speaker identity, respectively. While these effects were strong for familiar voices, they were smaller or nonsignificant for unfamiliar voices, suggesting that the effects depend on the previous creation of a multimodal representation of a person's identity. Moreover, the effects were reduced or eliminated when voices were combined with the same faces presented as static pictures, demonstrating that the effects do not simply reflect the use of facial identity as a "cue" for voice recognition. This is the first direct evidence for audiovisual integration in person recognition.

We assessed hemispheric differences in font-specific and abstractive repetition priming for famous persons' names. Participants performed speeded familiarity judgments for foveally presented famous and unfamiliar names. Famous target names were preceded by primes (150 ms) in the left or right visual field (LVF or RVF). Primes were either the same name as the target written in the same font (font-specific priming), the same name in a different font (abstractive priming), or a different name (unprimed condition). In reaction times, LH superiority was strong for abstractive priming across fonts, but was reduced to insignificance for font-specific priming. We observed 3 different ERP modulations of priming for target names: a small font-specific posterior N200 (160-220 ms), a left temporal N250r (220-300 ms), and an N400 modulation (300-500 ms). The left temporal N250r exhibited large and abstractive priming for RVF primes, but smaller and font-specific priming for LVF primes. N400 effects were observed in all priming conditions. With respect to previous findings that N200, N250r, and N400 reflect facilitation at the levels of font-specific encoding, lexical entries for names, and semantic processing, respectively, these findings suggest that the LH superiority for name processing is particularly pronounced for the access to abstractive lexical entries for written names, a process that may be mediated by the left fusiform cortex.

In "Thatcherized" faces, the eyes and mouth regions are turned upside-down. Only when presented upright they are perceived as severely distorted. Common theories explain this effect by the loss of configural information for inverted faces. We investigated neural correlates of Thatcherization using event related potentials (ERPs). Sixteen right-handed participants performed identity classifications on Thatcherized or original familiar faces, presented either for 34 ms or 200 ms at an orientation of either 0 degrees, 90 degrees or 180 degrees. For the occipito-temporal N170, we found (1) strong non-linear effects of orientation and (2) interactions between Thatcherization and orientation: Thatcherization resulted in larger N170 for upright faces, but smaller N170 for inverted faces. The novel finding of N170 effects of Thatcherization in inverted faces suggests differences in the neural encoding of Thatcherized and original inverted faces, even though Thatcherization escapes subjective perception in inverted faces.

We investigated the influence of task-irrelevant speaker variations on speechreading performance. In three experiments with video digitised faces presented either in dynamic, static-sequential, or static mode, participants performed speeded classifications on vowel utterances (German vowels /u/ and /i/). A Garner interference paradigm was used, in which speaker identity was task-irrelevant but could be either correlated, constant, or orthogonal to the vowel uttered. Reaction times for facial speech classifications were slowed by task-irrelevant speaker variations for dynamic stimuli. The results are discussed with reference to distributed models of face perception (Haxby et al, 2000 Trends in Cognitive Sciences 4 223-233) and the relevance of both dynamic information and speaker characteristics for speechreading.

Granular parakeratosis is an acquired, idiopathic disorder of keratinization typified by retention hyperkeratosis. It usually occurs in women at intertriginous sites. There have been only 2 reports of infants with granular parakeratosis to our knowledge. We describe 3 additional infants with granular parakeratosis. We demonstrate that infantile granular parakeratosis exhibits 2 clinical patterns: bilateral linear plaques in the inguinal folds; and erythematous geometric plaques underlying pressure points from the diaper. A thick, flakelike scale is present in both forms and is characteristic. Diaper wearing appears to play an important role in the genesis of infantile granular parakeratosis but the mechanisms are unclear. Therapeutic responsiveness to topical agents is ambiguous, however, spontaneous clearance after months to 1 year appears to be the rule.

Face recognition has been assumed to be independent of facial expression. We used familiar and unfamiliar faces that were morphed from a happy to an angry expression within a given identity. Participants performed speeded two-choice decisions according to whether or not a face was familiar. Consistent with earlier findings, reaction times for classifications of unfamiliar faces were independent of facial expressions. In contrast, expression clearly influenced the recognition of familiar faces. with fastest recognition for moderately happy expressions. This suggests that representations of familiar faces for recognition preserve some information about typical emotional expressions.

Interhemispheric cooperation can be indicated by enhanced performance when stimuli are presented to both visual fields relative to one visual field alone. This "bilateral gain" is seen for words but not pseudowords in lexical decision tasks, and has been attributed to the operation of interhemispheric cell assemblies that exist only for meaningful words with acquired cortical representations. Recently, a bilateral gain has been reported for famous but not unfamiliar faces in a face recognition task [Neuropsychologia 40 (2002) 1841]. In Experiment 1 of the present paper, participants performed familiarity decisions for faces that were presented to the left (LVF), the right (RVF), or to both visual fields (BVF). An advantage for BVF relative to both LVF and RVF stimuli was seen in reaction times (RTs) to famous faces, but this bilateral advantage was absent for unfamiliar faces. In Experiment 2, participants classified the expression (happy or neutral) of unfamiliar faces. No bilateral advantage was seen for expressions, although a right hemisphere superiority was seen in terms of higher accuracy for LVF and BVF trials relative to the RVF. Recognition of famous faces (but not of facial expressions) require access to acquired memory representations that may be instantiated via cortical cell assemblies, and it is suggested that interhemispheric cooperation depends on these acquired cortical representations.

We investigated immediate repetition effects in the recognition of famous faces by recording event-related brain potentials (ERPs) and reaction times (RTs). Participants recognized celebrities' faces that were preceded by either the same picture, a different picture of the same celebrity, or a different famous face. Face repetition caused two distinct ERP modulations. Repetitions elicited a strong modulation of an N250 component ( approximately 200-300 ms) over inferior temporal regions. The N250 modulation showed a degree of image specificity in that it was still significant for repetitions across different pictures, though reduced in amplitude. ERPs to repeated faces were also more positive than those to unprimed faces at parietal sites from 400 to 600 ms, but these later effects were largely independent of whether the same or a different image of the celebrity had served as prime. Finally, no influence of repetition was observed for the N170 component. Dipole source modelling suggested that the N250 repetition effect (N250r) may originate from the fusiform gyrus. In contrast, source localisation of the N170 implicated a significantly more posterior location, corresponding to a lateral occipitotemporal source outside the fusiform gyrus.

Initial symptoms of Rocky Mountain spotted fever (RMSF), a tick-borne illness caused by Rickettsia rickettsii, are nonspecific and include headache, gastrointestinal disturbances, malaise, and myalgias, followed by fever and rash. The classic triad of fever, rash, and history of tick exposure is uncommon at presentation. Clinical manifestations of RMSF range from virtually asymptomatic to severe. Because of the potentially fatal outcome of RMSF, presumptive clinical diagnosis and empiric antimicrobial therapy can be critical. We present the case of a 3-year-old girl from New York State who presented with fever and rash.

A case is presented of a 55-year old woman who developed an eruption suggestive of contact dermatitis on repeated occasions after receiving anesthesia for dermatologic procedures. Patch testing revealed a positive reaction to lidocaine. Basic structures of anesthetics are reviewed, and the classification of immunologically-mediated allergic reactions is discussed. The presence of cutaneous lidocaine allergy has profound implications for the field of dermatology.

In this reply to the comment by VanLancker and Ohnesorge (2002), we present the case that current evidence supports the role of left hemisphere in the recognition of famous personal names. We argue that this conclusion is in line not only with the results of Schweinberger, Landgrebe, Mohr, and Kaufmann (2002), but also with the evidence from methods other than divided visual field studies (e.g., PET and ERP studies). We show that our view is also supported by a new set of experiments that address a major concern raised by VanLancker and Ohnesorge in their comment and discuss why the evidence they present does not provide conclusive support to their right hemisphere hypothesis. One of the several possible reasons for this failure is that famous name stimuli may be less suitable than personally familiar stimuli to elicit personally relevant, affective aspects of recognition.

Names are thought to be represented in the brain differently from common nouns. Although this idea is supported by both theoretical and empirical arguments, the brain areas that are relevant for the recognition of personal names-and in particular the extent of right hemisphere involvement-remain controversial. We investigated the hypothesis that, unlike common nouns, personal names are represented preferentially by the right hemisphere (D. Van Lancker, 1991; D. Van Lancker et al., 1991; C. Ohnesorge & D. Van Lancker, 1999). Participants performed lexical decisions to common nouns and pseudowords (Experiment 1) or familiarity decisions to personal names (Experiment 2), which were presented briefly to the left or right visual fields. Asymmetries were small or absent for both pseudowords and unfamiliar names. For familiar names, both reaction times and error rates revealed strong advantages for the right visual field/left hemisphere (RVF/LH), which were comparable to the asymmetries for nouns. Familiar personal names may be represented by brain systems that differ from those representing common nouns, but current evidence does not suggest a distinct contribution of the right hemisphere to these brain systems., (Copyright 2001 Elsevier Science (USA).)

We investigated repetition priming in the recognition of famous people by recording event-related brain potentials (ERPs) and reaction times (RTs). Participants performed speeded two-choice responses depending on whether or not a stimulus showed a famous person. In Experiment 1, a facilitation was found in RTs to famous (but not to unfamiliar) faces when primed by the same face shown in an earlier priming phase of the experiment. In ERPs, an influence of repetition priming was observed neither for the N170 nor for a temporal N250 component which in previous studies had been shown to be sensitive to immediate face repetitions. ERPs to primed unfamiliar faces were more negative over right occipitotemporal areas than those to unprimed faces, but this effect was specific for repetitions of the same image, consistent with recent findings. In contrast, ERPs to primed familiar faces were more positive than those to unprimed faces at parietal sites from 500-600 ms after face onset, and these priming effects were comparable regardless of whether the same or a different image of the celebrity had served as prime. In Experiment 2, similar results were found for name recognition-a facilitation in RTs to primed familiar but not unfamiliar names, and a parietal positivity to primed names around 500-600 ms. ERP repetition effects showed comparable topographies for faces and names, consistent with the idea of a common underlying source. With reference to current models of face recognition, we suggest that these ERP repetition effects for familiar stimuli reflect a change in post-perceptual representations for people, rather than a neural correlate of recognition at a perceptual level.