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1.
Nat Commun ; 12(1): 4745, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362883

RESUMO

Spatial processing by receptive fields is a core property of the visual system. However, it is unknown how spatial processing in high-level regions contributes to recognition behavior. As face inversion is thought to disrupt typical holistic processing of information in faces, we mapped population receptive fields (pRFs) with upright and inverted faces in the human visual system. Here we show that in face-selective regions, but not primary visual cortex, pRFs and overall visual field coverage are smaller and shifted downward in response to face inversion. From these measurements, we successfully predict the relative behavioral detriment of face inversion at different positions in the visual field. This correspondence between neural measurements and behavior demonstrates how spatial processing in face-selective regions may enable holistic perception. These results not only show that spatial processing in high-level visual regions is dynamically used towards recognition, but also suggest a powerful approach for bridging neural computations by receptive fields to behavior.


Assuntos
Face/fisiologia , Reconhecimento Facial/fisiologia , Orientação/fisiologia , Processamento Espacial/fisiologia , Adulto , Comportamento , Encéfalo , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Reconhecimento Visual de Modelos/fisiologia , Reconhecimento Psicológico/fisiologia , Córtex Visual/fisiologia , Campos Visuais/fisiologia , Adulto Jovem
2.
Neuroimage ; 239: 118325, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34216773

RESUMO

Visual information involving facial identity and expression is crucial for social communication. Although the influence of facial features such as spatial frequency (SF) and luminance on face processing in visual areas has been studied extensively using grayscale stimuli, the combined effects of other features in this process have not been characterized. To determine the combined effects of different SFs and color, we created chromatic stimuli with low, high or no SF components, which bring distinct SF and color information into the ventral stream simultaneously. To obtain neural activity data with high spatiotemporal resolution we recorded face-selective responses (M170) using magnetoencephalography. We used a permutation test procedure with threshold-free cluster enhancement to assess statistical significance while resolving problems related to multiple comparisons and arbitrariness found in traditional statistical methods. We found that time windows with statistically significant threshold levels were distributed differently among the stimulus conditions. Face stimuli containing any SF components evoked M170 in the fusiform gyrus (FG), whereas a significant emotional effect on M170 was only observed with the original images. Low SF faces elicited larger activation of the FG and the inferior occipital gyrus than the original images, suggesting an interaction between low and high SF information processing. Interestingly, chromatic face stimuli without SF first activated color-selective regions and then the FG, indicating that facial color was processed according to a hierarchy in the ventral stream. These findings suggest complex effects of SFs in the presence of color information, reflected in M170, and unveil the detailed spatiotemporal dynamics of face processing in the human brain.


Assuntos
Algoritmos , Mapeamento Encefálico/métodos , Reconhecimento Facial/fisiologia , Imageamento por Ressonância Magnética/métodos , Magnetoencefalografia/métodos , Análise Espaço-Temporal , Córtex Visual/fisiologia , Percepção Visual/fisiologia , Adulto , Cor , Medo , Feminino , Humanos , Luz , Masculino , Adulto Jovem
3.
J Neurosci ; 41(37): 7864-7875, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34301829

RESUMO

Current theories of visual consciousness disagree about whether it emerges during early stages of processing in sensory brain regions or later when a widespread frontoparietal network becomes involved. Moreover, disentangling conscious perception from task-related postperceptual processes (e.g., report) and integrating results across different neuroscientific methods remain ongoing challenges. The present study addressed these problems using simultaneous EEG-fMRI and a specific inattentional blindness paradigm with three physically identical phases in female and male human participants. In phase 1, participants performed a distractor task during which line drawings of faces and control stimuli were presented centrally. While some participants spontaneously noticed the faces in phase 1, others remained inattentionally blind. In phase 2, all participants were made aware of the task-irrelevant faces but continued the distractor task. In phase 3, the faces became task-relevant. Bayesian analysis of brain responses demonstrated that conscious face perception was most strongly associated with activation in fusiform gyrus (fMRI) as well as the N170 and visual awareness negativity (EEG). Smaller awareness effects were revealed in the occipital and prefrontal cortex (fMRI). Task-relevant face processing, on the other hand, led to strong, extensive activation of occipitotemporal, frontoparietal, and attentional networks (fMRI). In EEG, it enhanced early negativities and elicited a pronounced P3b component. Overall, we provide evidence that conscious visual perception is linked with early processing in stimulus-specific sensory brain areas but may additionally involve prefrontal cortex. In contrast, the strong activation of widespread brain networks and the P3b are more likely associated with task-related processes.SIGNIFICANCE STATEMENT How does our brain generate visual consciousness-the subjective experience of what it is like to see, for example, a face? To date, it is hotly debated whether it emerges early in sensory brain regions or later when a widespread frontoparietal network is activated. Here, we use simultaneous fMRI and EEG for high spatial and temporal resolution and demonstrate that conscious face perception is predominantly linked to early and occipitotemporal processes, but also prefrontal activity. Task-related processes (e.g., decision-making), on the other hand, elicit brain-wide activations including late and strong frontoparietal activity. These findings challenge numerous previous studies and highlight the importance of investigating the neural correlates of consciousness in the absence of task relevance.


Assuntos
Encéfalo/fisiologia , Estado de Consciência/fisiologia , Reconhecimento Facial/fisiologia , Adulto , Atenção/fisiologia , Encéfalo/diagnóstico por imagem , Eletroencefalografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Percepção Visual/fisiologia , Adulto Jovem
4.
J Neurosci ; 41(37): 7876-7893, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34326145

RESUMO

Visual object recognition relies on elaborate sensory processes that transform retinal inputs to object representations, but it also requires decision-making processes that read out object representations and function over prolonged time scales. The computational properties of these decision-making processes remain underexplored for object recognition. Here, we study these computations by developing a stochastic multifeature face categorization task. Using quantitative models and tight control of spatiotemporal visual information, we demonstrate that human subjects (five males, eight females) categorize faces through an integration process that first linearly adds the evidence conferred by task-relevant features over space to create aggregated momentary evidence and then linearly integrates it over time with minimum information loss. Discrimination of stimuli along different category boundaries (e.g., identity or expression of a face) is implemented by adjusting feature weights of spatial integration. This linear but flexible integration process over space and time bridges past studies on simple perceptual decisions to complex object recognition behavior.SIGNIFICANCE STATEMENT Although simple perceptual decision-making such as discrimination of random dot motion has been successfully explained as accumulation of sensory evidence, we lack rigorous experimental paradigms to study the mechanisms underlying complex perceptual decision-making such as discrimination of naturalistic faces. We develop a stochastic multifeature face categorization task as a systematic approach to quantify the properties and potential limitations of the decision-making processes during object recognition. We show that human face categorization could be modeled as a linear integration of sensory evidence over space and time. Our framework to study object recognition as a spatiotemporal integration process is broadly applicable to other object categories and bridges past studies of object recognition and perceptual decision-making.


Assuntos
Tomada de Decisões/fisiologia , Reconhecimento Facial/fisiologia , Movimentos Oculares/fisiologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa , Tempo de Reação/fisiologia
5.
Sci Rep ; 11(1): 15326, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34321519

RESUMO

The risk for developing stress-related disorders is elevated in individuals with high alexithymia, a personality trait characterized by impaired emotional awareness and interpersonal relating. However, it is still unclear how alexithymia alters perceived psychosocial stress and which neurobiological substrates are mechanistically involved. To address this question, we examined freshmen during transition to university, given that this period entails psychosocial stress and frequently initiates psychopathology. Specifically, we used a functional magnetic resonance imaging emotional face matching task to probe emotional processing in 54 participants (39 women) at the beginning of the first year at university and 6 months later. Furthermore, we assessed alexithymia and monitored perceived psychosocial stress and loneliness via questionnaires for six consecutive months. Perceived psychosocial stress significantly increased over time and initial alexithymia predicted subjective stress experiences via enhanced loneliness. On the neural level, alexithymia was associated with lowered amygdala responses to emotional faces, while loneliness correlated with diminished reactivity in the anterior insular and anterior cingulate cortex. Furthermore, insula activity mediated the association between alexithymia and loneliness that predicted perceived psychosocial stress. Our findings are consistent with the notion that alexithymia exacerbates subjective stress via blunted insula reactivity and increased perception of social isolation.


Assuntos
Sintomas Afetivos/fisiopatologia , Córtex Cerebral/fisiopatologia , Reconhecimento Facial/fisiologia , Solidão/psicologia , Isolamento Social/psicologia , Estresse Psicológico/fisiopatologia , Sintomas Afetivos/diagnóstico por imagem , Sintomas Afetivos/psicologia , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/fisiopatologia , Córtex Cerebral/diagnóstico por imagem , Face/anatomia & histologia , Face/fisiologia , Feminino , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Interação Social , Estresse Psicológico/diagnóstico por imagem , Estresse Psicológico/psicologia , Inquéritos e Questionários , Adulto Jovem
6.
PLoS One ; 16(7): e0254396, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34255794

RESUMO

Technological advances in robotics have already produced robots that are indistinguishable from human beings. This technology is overcoming the uncanny valley, which refers to the unpleasant feelings that arise from humanoid robots that are similar in appearance to real humans to some extent. If humanoid robots with the same appearance are mass-produced and become commonplace, we may encounter circumstances in which people or human-like products have faces with the exact same appearance in the future. This leads to the following question: what impressions do clones elicit? To respond to this question, we examined what impressions images of people with the same face (clone images) induce. In the six studies we conducted, we consistently reported that clone images elicited higher eeriness than individuals with different faces; we named this new phenomenon the clone devaluation effect. We found that the clone devaluation effect reflected the perceived improbability of facial duplication. Moreover, this phenomenon was related to distinguishableness of each face, the duplication of identity, the background scene in observing clone faces, and avoidance reactions based on disgust sensitivity. These findings suggest that the clone devaluation effect is a product of multiple processes related to memory, emotion, and face recognition systems.


Assuntos
Reconhecimento Facial/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Adulto , Emoções/fisiologia , Expressão Facial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Robótica
7.
PLoS One ; 16(7): e0254438, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34292994

RESUMO

Evidence about the psychological functioning in individuals who survived the COVID-19 infectious is still rare in the literature. In this paper, we investigated fearful facial expressions recognition, as a behavioural means to assess psychological functioning. From May 15th, 2020 to January 30th, 2021, we enrolled sixty Italian individuals admitted in multiple Italian COVID-19 post-intensive care units. The detection and recognition of fearful facial expressions were assessed through an experimental task grounded on an attentional mechanism (i.e., the redundant target effect). According to the results, our participants showed an altered behaviour in detecting and recognizing fearful expressions. Specifically, their performance was in disagreement with the expected behavioural effect. Our study suggested altered processing of fearful expressions in individuals who survived the COVID-19 infectious. Such a difficulty might represent a crucial sign of psychological distress and it should be addressed in tailored psychological interventions in rehabilitative settings and after discharge.


Assuntos
COVID-19/psicologia , Reconhecimento Facial/fisiologia , Medo , Adulto , Feminino , Humanos , Masculino , Reconhecimento Psicológico/fisiologia
8.
Sci Rep ; 11(1): 11646, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-34079021

RESUMO

The study aimed to examine the neural mechanisms underlying implicit other-race face processing by the use of the masked and unmasked priming manipulation. Two types of prime-target pairs were presented while recording Event-related potentials (ERPs): Same face pairs (prime-target were identical faces), and Different face pairs (prime-target were different faces). Prime-target pairs were half Asian (other-race) and half Caucasian (own-race) faces. The face stimuli on each pair were of the same gender and race. Participants (all Caucasians) had to decide whether the target was a male or a female face (gender task). The prime face could be unmasked or masked. On the behavioral side, our findings showed a race effect, that is slower reaction times (RTs) for other-race than own-race face stimuli, regardless of masking. On the ERPs side, our data showed a race effect across all components analyzed (P100, N100, N200, P300), under both the unmasked and masked manipulations. Besides, we found, in the unmasked condition, a priming effect as a function of race on the N100, N200, and P300 components; but, interestingly, in the masked condition, only on the P300. Overall, our findings provide evidence that race information is available very early in the brain and can strongly activate and influence people's behaviors even without conscious awareness.


Assuntos
Encéfalo/fisiologia , Potenciais Evocados/fisiologia , Reconhecimento Facial/fisiologia , Mascaramento Perceptivo/fisiologia , Tempo de Reação/fisiologia , Adulto , Grupo com Ancestrais do Continente Asiático , Grupo com Ancestrais do Continente Europeu , Face/anatomia & histologia , Feminino , Humanos , Masculino , Estimulação Luminosa
9.
Sci Rep ; 11(1): 13184, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162959

RESUMO

Facial identity matching ability varies widely, ranging from prosopagnosic individuals (who exhibit profound impairments in face cognition/processing) to so-called super-recognizers (SRs), possessing exceptional capacities. Yet, despite the often consequential nature of face matching decisions-such as identity verification in security critical settings-ability assessments tendentially rely on simple performance metrics on a handful of heterogeneously related subprocesses, or in some cases only a single measured subprocess. Unfortunately, methodologies of this ilk leave contributions of stimulus information to observed variations in ability largely un(der)specified. Moreover, they are inadequate for addressing the qualitative or quantitative nature of differences between SRs' abilities and those of the general population. Here, therefore, we sought to investigate individual differences-among SRs identified using a novel conservative diagnostic framework, and neurotypical controls-by systematically varying retinal availability, bandwidth, and orientation of faces' spatial frequency content in two face matching experiments. Psychophysical evaluations of these parameters' contributions to ability reveal that SRs more consistently exploit the same spatial frequency information, rather than suggesting qualitatively different profiles between control observers and SRs. These findings stress the importance of optimizing procedures for SR identification, for example by including measures quantifying the consistency of individuals' behavior.


Assuntos
Reconhecimento Facial/fisiologia , Adulto , Aptidão , Feminino , Humanos , Individualidade , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fotografação/métodos , Psicofisiologia , Adulto Jovem
10.
PLoS One ; 16(6): e0250763, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34143788

RESUMO

This study examined involuntary capture of attention, overt attention, and stimulus valence and arousal ratings, all factors that can contribute to potential attentional biases to face and train objects in children with and without autism spectrum disorder (ASD). In the visual domain, faces are particularly captivating, and are thought to have a 'special status' in the attentional system. Research suggests that similar attentional biases may exist for other objects of expertise (e.g. birds for bird experts), providing support for the role of exposure in attention prioritization. Autistic individuals often have circumscribed interests around certain classes of objects, such as trains, that are related to vehicles and mechanical systems. This research aimed to determine whether this propensity in autistic individuals leads to stronger attention capture by trains, and perhaps weaker attention capture by faces, than what would be expected in non-autistic children. In Experiment 1, autistic children (6-14 years old) and age- and IQ-matched non-autistic children performed a visual search task where they manually indicated whether a target butterfly appeared amongst an array of face, train, and neutral distractors while their eye-movements were tracked. Autistic children were no less susceptible to attention capture by faces than non-autistic children. Overall, for both groups, trains captured attention more strongly than face stimuli and, trains had a larger effect on overt attention to the target stimuli, relative to face distractors. In Experiment 2, a new group of children (autistic and non-autistic) rated train stimuli as more interesting and exciting than the face stimuli, with no differences between groups. These results suggest that: (1) other objects (trains) can capture attention in a similar manner as faces, in both autistic and non-autistic children (2) attention capture is driven partly by voluntary attentional processes related to personal interest or affective responses to the stimuli.


Assuntos
Atenção/fisiologia , Transtorno do Espectro Autista/fisiopatologia , Movimentos Oculares/fisiologia , Reconhecimento Facial/fisiologia , Percepção Visual/fisiologia , Adolescente , Estudos de Casos e Controles , Criança , Feminino , Humanos , Masculino , Tempo de Reação
11.
Neuroimage ; 239: 118282, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34146711

RESUMO

Hypnotic suggestions can produce a broad range of perceptual experiences, including hallucinations. Visual hypnotic hallucinations differ in many ways from regular mental images. For example, they are usually experienced as automatic, vivid, and real images, typically compromising the sense of reality. While both hypnotic hallucination and mental imagery are believed to mainly rely on the activation of the visual cortex via top-down mechanisms, it is unknown how they differ in the neural processes they engage. Here we used an adaptation paradigm to test and compare top-down processing between hypnotic hallucination, mental imagery, and visual perception in very highly hypnotisable individuals whose ability to hallucinate was assessed. By measuring the N170/VPP event-related complex and using multivariate decoding analysis, we found that hypnotic hallucination of faces involves greater top-down activation of sensory processing through lateralised neural mechanisms in the right hemisphere compared to mental imagery. Our findings suggest that the neural signatures that distinguish hypnotically hallucinated faces from imagined faces lie in the right brain hemisphere.


Assuntos
Dominância Cerebral/fisiologia , Alucinações/fisiopatologia , Hipnose , Imaginação/fisiologia , Vias Neurais/fisiopatologia , Córtex Visual/fisiopatologia , Adolescente , Adulto , Eletroencefalografia , Potenciais Evocados , Face , Reconhecimento Facial/fisiologia , Pessoas Famosas , Feminino , Utensílios Domésticos , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação , Adulto Jovem
12.
J Alzheimers Dis ; 82(3): 939-950, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34120903

RESUMO

BACKGROUND: The study of emotion recognition could be crucial for detecting alterations in certain cognitive areas or as an early sign of neurological disorders. OBJECTIVE: The main objective of the study is to characterize research development on emotion recognition, identifying the intellectual structure that supports this area of knowledge, and the main lines of research attracting investigators' interest. METHODS: We identified publications on emotion recognition and dementia included in the Web of Science Core Collection, analyzing the scientific output and main disciplines involved in generating knowledge in the area. A co-citation analysis and an analysis of the bibliographic coupling between the retrieved documents elucidated the thematic orientations of the research and the reference works that constitute the foundation for development in the field. RESULTS: A total of 345 documents, with 24,282 bibliographic references between them, were included. This is an emerging research area, attracting the interest of investigators in Neurosciences, Psychology, Clinical Neurology, and Psychiatry, among other disciplines. Four prominent topic areas were identified, linked to frontotemporal dementia, autism spectrum disorders, Alzheimer's disease, and Parkinson's and Huntington disease. Many recent papers focus on the detection of mild cognitive impairment. CONCLUSION: Impaired emotion recognition may be a key sign facilitating the diagnosis and early treatment of different neurodegenerative diseases as well as for triggering the necessary provision of social and family support, explaining the growing research interest in this area.


Assuntos
Demência/diagnóstico , Demência/psicologia , Regulação Emocional/fisiologia , Expressão Facial , Reconhecimento Facial/fisiologia , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/psicologia , Análise por Conglomerados , Emoções/fisiologia , Humanos
13.
Sci Rep ; 11(1): 11314, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-34059736

RESUMO

Subjective memory complaints (SMCs) are commonly related to aging, but they are also presented by young adults. Their neurophysiological mechanisms are not thoroughly understood, although some aspects related to affective state have been mentioned. Here, we investigated whether facial emotion processing is different in young people with (n = 41) and without (n = 39) SMCs who were exposed to positive, negative, and neutral faces, by recording the event-related potential (ERP) activity. From the ERP activity, the N170 (an index of face processing) and the LPP (an index of motivated attention) components were extracted. Regarding the N170, results showed less amplitude for positive and neutral faces in the participants with SMCs than in those without SMCs. Moreover, women with SMCs displayed longer latencies for neutral faces than women without SMCs. No significant differences were found between the groups in the LPP component. Together, our findings suggest deficits in an early stage of facial emotion processing in young people with SMCs, and they emphasize the importance of further examining affective dimensions.


Assuntos
Potenciais Evocados , Reconhecimento Facial/fisiologia , Transtornos da Memória/fisiopatologia , Adolescente , Adulto , Estudos de Casos e Controles , Autoavaliação Diagnóstica , Feminino , Humanos , Masculino , Adulto Jovem
14.
Neuroimage ; 237: 118137, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-33951512

RESUMO

The goal of our study was to use functional connectivity to map brain function to self-reports of negative emotion. In a large dataset of healthy individuals derived from the Human Connectome Project (N = 652), first we quantified functional connectivity during a negative face-matching task to isolate patterns induced by emotional stimuli. Then, we did the same in a complementary task-free resting state condition. To identify the relationship between functional connectivity in these two conditions and self-reports of negative emotion, we introduce group regularized canonical correlation analysis (GRCCA), a novel algorithm extending canonical correlations analysis to model the shared common properties of functional connectivity within established brain networks. To minimize overfitting, we optimized the regularization parameters of GRCCA using cross-validation and tested the significance of our results in a held-out portion of the data set using permutations. GRCCA consistently outperformed plain regularized canonical correlation analysis. The only canonical correlation that generalized to the held-out test set was based on resting state data (r = 0.175, permutation test p = 0.021). This canonical correlation loaded primarily on Anger-aggression. It showed high loadings in the cingulate, orbitofrontal, superior parietal, auditory and visual cortices, as well as in the insula. Subcortically, we observed high loadings in the globus pallidus. Regarding brain networks, it loaded primarily on the primary visual, orbito-affective and ventral multimodal networks. Here, we present the first neuroimaging application of GRCCA, a novel algorithm for regularized canonical correlation analyses that takes into account grouping of the variables during the regularization scheme. Using GRCCA, we demonstrate that functional connections involving the visual, orbito-affective and multimodal networks are promising targets for investigating functional correlates of subjective anger and aggression. Crucially, our approach and findings also highlight the need of cross-validation, regularization and testing on held out data for correlational neuroimaging studies to avoid inflated effects.


Assuntos
Ira/fisiologia , Encéfalo/fisiologia , Conectoma/métodos , Reconhecimento Facial/fisiologia , Medo/fisiologia , Rede Nervosa/fisiologia , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Autorrelato , Percepção Social , Adulto Jovem
15.
J Neurosci ; 41(26): 5687-5698, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34031162

RESUMO

The successful recognition of familiar persons is critical for social interactions. Despite extensive research on the neural representations of familiar faces, we know little about how such representations unfold as someone becomes familiar. In three EEG experiments on human participants of both sexes, we elucidated how representations of face familiarity and identity emerge from different qualities of familiarization: brief perceptual exposure (Experiment 1), extensive media familiarization (Experiment 2), and real-life personal familiarization (Experiment 3). Time-resolved representational similarity analysis revealed that familiarization quality has a profound impact on representations of face familiarity: they were strongly visible after personal familiarization, weaker after media familiarization, and absent after perceptual familiarization. Across all experiments, we found no enhancement of face identity representation, suggesting that familiarity and identity representations emerge independently during face familiarization. Our results emphasize the importance of extensive, real-life familiarization for the emergence of robust face familiarity representations, constraining models of face perception and recognition memory.SIGNIFICANCE STATEMENT Despite extensive research on the neural representations of familiar faces, we know little about how such representations unfold as someone becomes familiar. To elucidate how face representations change as we get familiar with someone, we conducted three EEG experiments where we used brief perceptual exposure, extensive media familiarization, or real-life personal familiarization. Using multivariate representational similarity analysis, we demonstrate that the method of familiarization has a profound impact on face representations, and emphasize the importance of real-life familiarization. Additionally, familiarization shapes representations of face familiarity and identity differently: as we get to know someone, familiarity signals seem to appear before the formation of identity representations.


Assuntos
Encéfalo/fisiologia , Reconhecimento Facial/fisiologia , Reconhecimento Psicológico/fisiologia , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Adulto Jovem
16.
J Neurosci ; 41(25): 5511-5521, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34016715

RESUMO

The ventral visual stream of the human brain is subdivided into patches with categorical stimulus preferences, like faces or scenes. However, the functional organization within these areas is less clear. Here, we used functional magnetic resonance imaging and vertex-wise tuning models to independently probe spatial and face-part preferences in the inferior occipital gyrus (IOG) of healthy adult males and females. The majority of responses were well explained by Gaussian population tuning curves for both retinotopic location and the preferred relative position within a face. Parameter maps revealed a common gradient of spatial and face-part selectivity, with the width of tuning curves drastically increasing from posterior to anterior IOG. Tuning peaks clustered more idiosyncratically but were also correlated across maps of visual and face space. Preferences for the upper visual field went along with significantly increased coverage of the upper half of the face, matching recently discovered biases in human perception. Our findings reveal a broad range of neural face-part selectivity in IOG, ranging from narrow to "holistic." IOG is functionally organized along this gradient, which in turn is correlated with retinotopy.SIGNIFICANCE STATEMENT Brain imaging has revealed a lot about the large-scale organization of the human brain and visual system. For example, occipital cortex contains map-like representations of the visual field, while neurons in ventral areas cluster into patches with categorical preferences, like faces or scenes. Much less is known about the functional organization within these areas. Here, we focused on a well established face-preferring area-the inferior occipital gyrus (IOG). A novel neuroimaging paradigm allowed us to map the retinotopic and face-part tuning of many recording sites in IOG independently. We found a steep posterior-anterior gradient of decreasing face-part selectivity, which correlated with retinotopy. This suggests the functional role of ventral areas is not uniform and may follow retinotopic "protomaps."


Assuntos
Reconhecimento Facial/fisiologia , Lobo Occipital/fisiologia , Adulto , Mapeamento Encefálico/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Vias Visuais/fisiologia
17.
PLoS One ; 16(5): e0251186, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33983978

RESUMO

Accurate inferences of the emotional state of conversation participants can be critical in shaping analysis and interpretation of conversational exchanges. In qualitative analyses of discourse, most labelling of the perceived emotional state of conversation participants is performed by hand, and is limited to selected moments where an analyst may believe that emotional information is valuable for interpretation. This reliance on manual labelling processes can have implications for repeatability and objectivity, both in terms of accuracy, but also in terms of changes in emotional state that might go unnoticed. In this paper we introduce a qualitative discourse analytic support method intended to support the labelling of emotional state of conversational participants over time. We demonstrate the utility of the technique using a suite of well-studied broadcast interviews, taking a particular focus on identifying instances of inter-speaker conflict. Our findings indicate that this two-step machine learning approach can help decode how moments of conflict arise, sustain, and are resolved through the mapping of emotion over time. We show how such a method can provide useful evidence of the change in emotional state by interlocutors which could be useful to prompt and support further in-depth study.


Assuntos
Emoções/fisiologia , Estudos de Avaliação como Assunto , Comunicação , Conflito Psicológico , Aprendizado Profundo , Reconhecimento Facial/fisiologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Modelos Teóricos
18.
Neuroimage ; 236: 118034, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33839265

RESUMO

Magnetoencephalography (MEG) offers a unique way to noninvasively investigate millisecond-order cortical activities by mapping sensor signals (magnetic fields outside the head) to cortical current sources using current source reconstruction methods. Current source reconstruction is defined as an ill-posed inverse problem, since the number of sensors is less than the number of current sources. One powerful approach to solving this problem is to use functional MRI (fMRI) data as a spatial constraint, although it boosts the cost of measurement and the burden on subjects. Here, we show how to use the meta-analysis fMRI data synthesized from thousands of papers instead of the individually recorded fMRI data. To mitigate the differences between the meta-analysis and individual data, the former are imported as prior information of the hierarchical Bayesian estimation. Using realistic simulations, we found out the performance of current source reconstruction using meta-analysis fMRI data to be better than that using low-quality individual fMRI data and conventional methods. By applying experimental data of a face recognition task, we qualitatively confirmed that group analysis results using the meta-analysis fMRI data showed a tendency similar to the results using the individual fMRI data. Our results indicate that the use of meta-analysis fMRI data improves current source reconstruction without additional measurement costs. We assume the proposed method would have greater effect for modalities with lower measurement costs, such as optically pumped magnetometers.


Assuntos
Córtex Cerebral/fisiologia , Neuroimagem Funcional/métodos , Magnetoencefalografia/métodos , Metanálise como Assunto , Adulto , Mapeamento Encefálico/métodos , Córtex Cerebral/diagnóstico por imagem , Simulação por Computador , Conjuntos de Dados como Assunto , Reconhecimento Facial/fisiologia , Humanos , Imageamento por Ressonância Magnética
19.
Neuroimage ; 236: 118028, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33930538

RESUMO

Surprising scenarios can have different behavioural and neuronal consequences depending on the violation of the expectation. On the one hand, previous research has shown that the omission of a visual stimulus results in a robust cortical response representing that missing stimulus, a so-called negative prediction error. On the other hand, a large amount of studies revealed positive prediction error signals, entailing an increased neural response that can be attributed to the experience of a surprising, unexpected stimulus. However, there has been no evidence, so far, regarding how and when these prediction error signals co-occur. Here, we argue that the omission of an expected stimulus can and often does coincide with the appearance of an unexpected one. Therefore, we investigated whether positive and negative prediction error signals evoked by unpredicted cross-category stimulus transitions would temporally coincide during a speeded forced-choice fMRI paradigm. Foremost, our findings provide evidence of a behavioural effect regarding the facilitation of responses linked to expected stimuli. In addition, we obtained evidence for negative prediction error signals as seen in differential activation of FFA and PPA during unexpected place and face trials, respectively. Lastly, a psychophysiological interaction analysis revealed evidence for positive prediction error signals represented by context-dependent functional coupling between the right IFG and FFA or PPA, respectively, implicating a network that updates the internal representation after the appearance of an unexpected stimulus through involvement of this frontal area. The current results are consistent with a predictive coding account of cognition and underline the importance of considering the potential dual nature of expectation violations. Furthermore, our results put forward that positive and negative prediction error signalling can be directly linked to regions associated with the processing of different stimulus categories.


Assuntos
Antecipação Psicológica/fisiologia , Giro Para-Hipocampal/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Córtex Pré-Frontal/fisiologia , Percepção Espacial/fisiologia , Lobo Temporal/fisiologia , Adolescente , Adulto , Mapeamento Encefálico , Reconhecimento Facial/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Giro Para-Hipocampal/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Lobo Temporal/diagnóstico por imagem , Adulto Jovem
20.
PLoS One ; 16(4): e0248785, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33793593

RESUMO

Anterior temporal lobectomy (ATL) is the most common surgical treatment for drug-resistant temporal lobe epilepsy (TLE). Right ATL has been reported to reduce facial memory ability in patients with TLE, as indicated by poor performance on the Warrington Recognition Memory Test for Faces (RMF), which is commonly used to evaluate visual memory in these patients. However, little is known about whether patients with TLE exhibit difficulties in identifying faces in daily life after ATL. The aim of this study was to investigate facial memory ability and self-awareness of face identification difficulties in patients with TLE after ATL. Sixteen patients with TLE after right ATL, 14 patients with TLE after left ATL, and 29 healthy controls were enrolled in this study. We developed the multiview face recognition test (MFRT), which comprises a learning phase (one or three frontal face images without external facial feature information) and a recognition phase (frontal, oblique, or noise-masked face images). Facial memory abilities were examined in all participants using the MFRT and RMF, and self-awareness of difficulties in face identification was evaluated using the 20-item prosopagnosia index (PI20), which has been widely used to assess developmental prosopagnosia. The MFRT performance in patients with TLE after ATL was significantly worse than that in healthy controls regardless of the resected side, whereas the RMF scores in patients with TLE were significantly worse than those in healthy controls only after right ATL. The MFRT performance in patients with TLE after both left and right ATL was more influenced by working memory load than that in healthy controls. The PI20 scores revealed that patients with TLE after left ATL were aware of their difficulties in identifying faces. These findings suggest that patients with TLE not only after right ATL but also after left ATL might have difficulties in face identification.


Assuntos
Epilepsia do Lobo Temporal/cirurgia , Reconhecimento Facial/fisiologia , Transtornos da Memória/etiologia , Adulto , Lobectomia Temporal Anterior , Estudos de Casos e Controles , Epilepsia do Lobo Temporal/patologia , Feminino , Humanos , Masculino , Transtornos da Memória/patologia , Testes Neuropsicológicos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/patologia
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