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1.
Acta Psychol (Amst) ; 247: 104330, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38852319

RESUMO

In the context of blindness, studies on the recognition of facial expressions of emotions by touch are essential to define the compensatory touch abilities and to create adapted tools on emotions. This study is the first to examine the effect of visual experience in the recognition of tactile drawings of facial expressions of emotions by children with different visual experiences. To this end, we compared the recognition rates of tactile drawings of emotions between blind children, children with low vision and sighted children aged 6-12 years. Results revealed no effect of visual experience on recognition rates. However, an effect of emotions and an interaction effect between emotions and visual experience were found. Indeed, while all children had a low average recognition rate, the drawings of fear, anger and disgust were particularly poorly recognized. Moreover, sighted children were significantly better at recognizing the drawings of surprise and sadness than the blind children who only showed high recognition rates for joy. The results of this study support the importance of developing emotion tools that can be understood by children with different visual experiences.

2.
Emotion ; 23(8): 2399-2419, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36996175

RESUMO

In the current study, we examined the role of task-related top-down mechanisms in the recognition of facial expressions. An expression of increasing intensity was displayed at a frequency of 1.5 Hz among the neutral faces of the same model that was displayed at a frequency of 12 Hz (i.e., 12 frames per second, with the expression occurring every eight frames). Twenty-two participants were asked either to recognize the emotion at the expression-specific frequency (1.5 Hz) or to perform an orthogonal task in separate blocks, while a scalp electroencephalogram (EEG) was recorded. A significant 1.5 Hz response emerged with the increase in expressive intensity over the medial occipital, right and left occipitotemporal, and centro-frontal regions. In these three regions, the magnitude of this response was greater when participants were involved in expression recognition, especially when the intensity of expression was low and ambiguous. Time-domain analysis revealed that engagement in the explicit recognition of facial expression caused a modulation of the response even before the onset of the expression over centro-frontal regions. The response was then amplified over the medial occipital and right and left occipitotemporal regions. Overall, the procedure developed in the present study allowed us to document different stages of the voluntary recognition of facial expressions, from detection to recognition, through the implementation of task-related top-down mechanisms that modulated the incoming information flow. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Expressão Facial , Reconhecimento Facial , Humanos , Eletroencefalografia/métodos , Emoções/fisiologia , Lobo Frontal , Reconhecimento Psicológico , Reconhecimento Facial/fisiologia
3.
Front Neurosci ; 16: 901013, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36061610

RESUMO

Infants' ability to discriminate facial expressions has been widely explored, but little is known about the rapid and automatic ability to discriminate a given expression against many others in a single experiment. Here we investigated the development of facial expression discrimination in infancy with fast periodic visual stimulation coupled with scalp electroencephalography (EEG). EEG was recorded in eighteen 3.5- and eighteen 7-month-old infants presented with a female face expressing disgust, happiness, or a neutral emotion (in different stimulation sequences) at a base stimulation frequency of 6 Hz. Pictures of the same individual expressing other emotions (either anger, disgust, fear, happiness, sadness, or neutrality, randomly and excluding the expression presented at the base frequency) were introduced every six stimuli (at 1 Hz). Frequency-domain analysis revealed an objective (i.e., at the predefined 1-Hz frequency and harmonics) expression-change brain response in both 3.5- and 7-month-olds, indicating the visual discrimination of various expressions from disgust, happiness and neutrality from these early ages. At 3.5 months, the responses to the discrimination from disgust and happiness expressions were located mainly on medial occipital sites, whereas a more lateral topography was found for the response to the discrimination from neutrality, suggesting that expression discrimination from an emotionally neutral face relies on distinct visual cues than discrimination from a disgust or happy face. Finally, expression discrimination from happiness was associated with a reduced activity over posterior areas and an additional response over central frontal scalp regions at 7 months as compared to 3.5 months. This result suggests developmental changes in the processing of happiness expressions as compared to negative/neutral ones within this age range.

4.
Neuroimage ; 255: 119181, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35413443

RESUMO

Visual categorization is the brain ability to rapidly and automatically respond to a certain category of inputs. Whether category-selective neural responses are purely visual or can be influenced by other sensory modalities remains unclear. Here, we test whether odors modulate visual categorization, expecting that odors facilitate the neural categorization of congruent visual objects, especially when the visual category is ambiguous. Scalp electroencephalogram (EEG) was recorded while natural images depicting various objects were displayed in rapid 12-Hz streams (i.e., 12 images / second) and variable exemplars of a target category (either human faces, cars, or facelike objects in dedicated sequences) were interleaved every 9th stimulus to tag category-selective responses at 12/9 = 1.33 Hz in the EEG frequency spectrum. During visual stimulation, participants (N = 26) were implicitly exposed to odor contexts (either body, gasoline or baseline odors) and performed an orthogonal cross-detection task. We identify clear category-selective responses to every category over the occipito-temporal cortex, with the largest response for human faces and the lowest for facelike objects. Critically, body odor boosts the response to the ambiguous facelike objects (i.e., either perceived as nonface objects or faces) over the right hemisphere, especially for participants reporting their presence post-stimulation. By contrast, odors do not significantly modulate other category-selective responses, nor the general visual response recorded at 12 Hz, revealing a specific influence on the categorization of congruent ambiguous stimuli. Overall, these findings support the view that the brain actively uses cues from the different senses to readily categorize visual inputs, and that olfaction, which has long been considered as poorly functional in humans, is well placed to disambiguate visual information.


Assuntos
Mapeamento Encefálico , Olfato , Encéfalo/fisiologia , Eletroencefalografia , Humanos , Odorantes , Estimulação Luminosa/métodos
5.
Acta Psychol (Amst) ; 225: 103553, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35279432

RESUMO

Emotion regulation develops from the earliest years of a child's life and mostly through visual information. Considering the importance of emotion regulation in daily life situations, it is important to study the effect of visual experience on the development of this ability. This study is the first to examine the effect of visual experience and age in emotion regulation by comparing groups of children with different visual status and age. For this purpose, after testing the reliability and consistency of the French version of Emotion Regulation Checklist (ERC-vf) with 245 parents of blind, visually impaired and sighted children aged 3-5, 6-8 or 9-12 years, we conducted analyses on the effect of visual status and age on emotion regulation composite scores. The first result confirmed that the ERC-vf can be reliably used on populations of blind and visually impaired children. The second result revealed an effect of visual status on ER composite scores of emotion regulation: Blind children and visually impaired children each had significantly lower composite scores than sighted children. Moreover, the effect of age and the interaction between age and visual status were not significant on ER composite scores. The ER subscale results suggest, however, that age may have a variable effect for blind and visually impaired children as blind children's scores become lower and those of visually impaired children become equal to sighted children with age. The results of our study may help the children's entourage to better adapt their interactions in a context of visual impairment.


Assuntos
Regulação Emocional , Pessoas com Deficiência Visual , Cegueira , Criança , Pré-Escolar , Humanos , Pais , Reprodutibilidade dos Testes , Inquéritos e Questionários , Pessoas com Deficiência Visual/psicologia
6.
Cognition ; 222: 105016, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35030358

RESUMO

The human brain rapidly and automatically categorizes faces vs. other visual objects. However, whether face-selective neural activity predicts the subjective experience of a face - perceptual awareness - is debated. To clarify this issue, here we use face pareidolia, i.e., the illusory perception of a face, as a proxy to relate the neural categorization of a variety of facelike objects to conscious face perception. In Experiment 1, scalp electroencephalogram (EEG) is recorded while pictures of human faces or facelike objects - in different stimulation sequences - are interleaved every second (i.e., at 1 Hz) in a rapid 6-Hz train of natural images of nonface objects. Participants do not perform any explicit face categorization task during stimulation, and report whether they perceived illusory faces post-stimulation. A robust categorization response to facelike objects is identified at 1 Hz and harmonics in the EEG frequency spectrum with a facelike occipito-temporal topography. Across all individuals, the facelike categorization response is of about 20% of the response to human faces, but more strongly right-lateralized. Critically, its amplitude is much larger in participants who report having perceived illusory faces. In Experiment 2, facelike or matched nonface objects from the same categories appear at 1 Hz in sequences of nonface objects presented at variable stimulation rates (60 Hz to 12 Hz) and participants explicitly report after each sequence whether they perceived illusory faces. The facelike categorization response already emerges at the shortest stimulus duration (i.e., 17 ms at 60 Hz) and predicts the behavioral report of conscious perception. Strikingly, neural facelike-selectivity emerges exclusively when participants report illusory faces. Collectively, these experiments characterize a neural signature of face pareidolia in the context of rapid categorization, supporting the view that face-selective brain activity reliably predicts the subjective experience of a face from a single glance at a variety of stimuli.


Assuntos
Reconhecimento Facial , Ilusões , Encéfalo/fisiologia , Mapeamento Encefálico , Eletroencefalografia , Reconhecimento Facial/fisiologia , Humanos , Estimulação Luminosa/métodos
7.
Proc Natl Acad Sci U S A ; 118(21)2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34001601

RESUMO

Understanding how the young infant brain starts to categorize the flurry of ambiguous sensory inputs coming in from its complex environment is of primary scientific interest. Here, we test the hypothesis that senses other than vision play a key role in initiating complex visual categorizations in 20 4-mo-old infants exposed either to a baseline odor or to their mother's odor while their electroencephalogram (EEG) is recorded. Various natural images of objects are presented at a 6-Hz rate (six images/second), with face-like object configurations of the same object categories (i.e., eliciting face pareidolia in adults) interleaved every sixth stimulus (i.e., 1 Hz). In the baseline odor context, a weak neural categorization response to face-like stimuli appears at 1 Hz in the EEG frequency spectrum over bilateral occipitotemporal regions. Critically, this face-like-selective response is magnified and becomes right lateralized in the presence of maternal body odor. This reveals that nonvisual cues systematically associated with human faces in the infant's experience shape the interpretation of face-like configurations as faces in the right hemisphere, dominant for face categorization. At the individual level, this intersensory influence is particularly effective when there is no trace of face-like categorization in the baseline odor context. These observations provide evidence for the early tuning of face-(like)-selective activity from multisensory inputs in the developing brain, suggesting that perceptual development integrates information across the senses for efficient category acquisition, with early maturing systems such as olfaction driving the acquisition of categories in later-developing systems such as vision.


Assuntos
Encéfalo/fisiologia , Reconhecimento Facial/fisiologia , Odorantes , Visão Ocular/fisiologia , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Eletroencefalografia , Feminino , Humanos , Lactente , Masculino , Estimulação Luminosa
8.
PLoS One ; 16(1): e0245777, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33497409

RESUMO

Recognizing facial expressions of emotions is a fundamental ability for adaptation to the social environment. To date, it remains unclear whether the spatial distribution of eye movements predicts accurate recognition or, on the contrary, confusion in the recognition of facial emotions. In the present study, we asked participants to recognize facial emotions while monitoring their gaze behavior using eye-tracking technology. In Experiment 1a, 40 participants (20 women) performed a classic facial emotion recognition task with a 5-choice procedure (anger, disgust, fear, happiness, sadness). In Experiment 1b, a second group of 40 participants (20 women) was exposed to the same materials and procedure except that they were instructed to say whether (i.e., Yes/No response) the face expressed a specific emotion (e.g., anger), with the five emotion categories tested in distinct blocks. In Experiment 2, two groups of 32 participants performed the same task as in Experiment 1a while exposed to partial facial expressions composed of actions units (AUs) present or absent in some parts of the face (top, middle, or bottom). The coding of the AUs produced by the models showed complex facial configurations for most emotional expressions, with several AUs in common. Eye-tracking data indicated that relevant facial actions were actively gazed at by the decoders during both accurate recognition and errors. False recognition was mainly associated with the additional visual exploration of less relevant facial actions in regions containing ambiguous AUs or AUs relevant to other emotional expressions. Finally, the recognition of facial emotions from partial expressions showed that no single facial actions were necessary to effectively communicate an emotional state. In contrast, the recognition of facial emotions relied on the integration of a complex set of facial cues.


Assuntos
Emoções , Movimentos Oculares , Reconhecimento Facial , Adulto , Feminino , Humanos , Masculino
9.
Artigo em Inglês | MEDLINE | ID: mdl-32787505

RESUMO

Studies on aging and hedonic judgment of odors have never been addressed within the empirical frameworks of age-related changes in emotion which state that advancing age is associated with a reduced negativity bias and a less pronounced differentiation between hedonic valence and emotional intensity judgments. Our aim was to examine and extend these age-related effects into the field of odors. Thirty-eight younger adults and 40 older adults were asked to evaluate the hedonic valence, emotional intensity, and familiarity of 50 odors controlled for their pleasantness. Compared to younger adults, older adults rated unpleasant odorants as less unpleasant and showed an increased relationship between hedonic valence and emotional intensity ratings. This yields evidence of reduced negativity bias and emotional dedifferentiation in response to odors. Such data suggest that when faced with odors, older people exhibit a reduction of emotional dimensionality leading them to distort emotional processing in a less negative direction.


Assuntos
Envelhecimento/fisiologia , Emoções/fisiologia , Percepção Olfatória/fisiologia , Reconhecimento Psicológico/fisiologia , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prazer/fisiologia , Adulto Jovem
10.
Biol Psychol ; 158: 108005, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33290848

RESUMO

The influence of odor valence on expressive-face perception remains unclear. Here, three "valenced" odor contexts (pleasant, unpleasant, control) were diffused while scalp electroencephalogram (EEG) was recorded in 18 participants presented with expressive faces alternating at a 6-Hz rate. One facial expression (happiness, disgust or neutrality) repeatedly arose every 6 face pictures to isolate its discrimination from other expressions at 1 Hz and harmonics in the EEG spectrum. The amplitude of the brain response to neutrality was larger in the pleasant vs. control odor context, and fewer electrodes responded in the unpleasant odor context. The number of responding electrodes was reduced for disgust in both odor contexts. The response to happiness was unchanged between odor conditions. Overall, these observations suggest that valenced odors influence the neural discrimination of facial expressions depending on both face and odor hedonic valence, especially for the emotionally ambiguous neutral expression.


Assuntos
Expressão Facial , Reconhecimento Facial , Encéfalo , Emoções , Humanos , Odorantes
11.
Infancy ; 25(2): 151-164, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32749059

RESUMO

Little is known about the effects of olfaction on visual processing during infancy. We investigated whether and how an infant's own mother's body odor or another mother's body odor affects 4-month-old infants' looking at their mother's face when it is paired with a stranger's face. In Experiment 1, infants were exposed to their mother's body odor or to a control odor, while in Experiment 2, infants were exposed to a stranger mother's body odor while their visual preferences were recorded. Results revealed that infants looked more at the stranger's female face in presence of the control odor but that they looked more at their mother's face in the context of any mother's body odors. This effect was due to a reduction of looking at the stranger's face. These findings suggest that infants react similarly to the body odor of any mother and add to the growing body of evidence indicating that olfactory stimulation represents a pervasive aspect of infant multisensory perception.


Assuntos
Face , Relações Mãe-Filho , Odorantes , Análise de Variância , Feminino , Humanos , Lactente , Masculino , Mães , Estimulação Luminosa
12.
Cortex ; 127: 150-161, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32200287

RESUMO

Sex categorization is essential for mate choice and social interactions in many animal species. In humans, sex categorization is readily performed from the face. However, clear neural markers of face-sex categorization, i.e., common responses to widely variable individuals from one sex, have not been identified so far in humans. To isolate a direct signature of rapid and automatic face-sex categorization generalized across a wide range of variable exemplars, we recorded scalp electroencephalogram (EEG) from 32 participants (16 females) while they were exposed to variable natural face images from one sex alternating at a rapid rate of 6 Hz (i.e., 6 images per second). Images from the other sex were inserted every 6th stimulus (i.e., at a 1-Hz rate). A robust categorization response to both sex contrasts emerged at 1 Hz and harmonics in the EEG frequency spectrum over the occipito-temporal cortex of most participants. The response was larger for female faces presented among male faces than the reverse, suggesting that the two sex categories are not equally homogenous. This asymmetrical response pattern disappeared for upside-down faces, ruling out the contribution of low-level physical variability across images. Overall, these observations demonstrate that sex categorization occurs automatically after a single glance at natural face images and can be objectively isolated and quantified in the human brain within a few minutes.


Assuntos
Mapeamento Encefálico , Eletroencefalografia , Encéfalo , Feminino , Humanos , Masculino , Reconhecimento Visual de Modelos , Estimulação Luminosa , Lobo Temporal
13.
Neuroimage ; 204: 116218, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31550510

RESUMO

Humans exhibit a marked specialization to process the most experienced facial morphologies. In particular, nonhuman primate faces are poorly discriminated compared to human faces in behavioral tasks. So far however, a clear and consistent marker that quantifies our expertise in human over monkey face discrimination directly from brain activity is lacking. Here, using scalp electroencephalography (EEG), we isolate a direct signature of individuation abilities for human and nonhuman (i.e., macaque faces) primate faces. Human or monkey faces were rapidly presented at a base rate of 12 Hz in upright or inverted orientations while participants performed an orthogonal behavioral task. In each stimulation sequence, eight face images of one individual were used as base stimuli, while images of other individuals were briefly introduced every 9th stimulus to quantify an identity-change response at 1.33 Hz and harmonics (i.e., integer multiples) in the EEG frequency spectrum. The brain response to upright human faces was twice as large as to monkey faces, and reduced following picture-plane inversion for human faces only. This reflects the disruption of high-level face identity discrimination developed for the canonical upright human face. No difference was observed between upright monkey faces and inverted human faces, suggesting non-expert visual processes for those two face formats associated with little experience. In addition, the size of the inversion effect for human, but not monkey faces, was predictive of the expertise effect (i.e., difference between upright human and monkey faces) at the individual level. This result suggests a selective ability to discriminate human faces that does not contribute to the individuation of other unexperienced face morphologies such as monkey faces. Overall, these findings indicate that human expertise for conspecific face discrimination can be isolated and quantified in individual human brains.


Assuntos
Córtex Cerebral/fisiologia , Discriminação Psicológica/fisiologia , Reconhecimento Facial/fisiologia , Prática Psicológica , Percepção Espacial/fisiologia , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Adulto Jovem
14.
Dev Sci ; 23(2): e12877, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31175678

RESUMO

To successfully interact with a rich and ambiguous visual environment, the human brain learns to differentiate visual stimuli and to produce the same response to subsets of these stimuli despite their physical difference. Although this visual categorization function is traditionally investigated from a unisensory perspective, its early development is inherently constrained by multisensory inputs. In particular, an early-maturing sensory system such as olfaction is ideally suited to support the immature visual system in infancy by providing stability and familiarity to a rapidly changing visual environment. Here, we test the hypothesis that rapid visual categorization of salient visual signals for the young infant brain, human faces, is shaped by another highly relevant human-related input from the olfactory system, the mother's body odor. We observe that a right-hemispheric neural signature of single-glance face categorization from natural images is significantly enhanced in the maternal versus a control odor context in individual 4-month-old infant brains. A lack of difference between odor conditions for the common brain response elicited by both face and non-face images rules out a mere enhancement of arousal or visual attention in the maternal odor context. These observations show that face-selective neural activity in infancy is mediated by the presence of a (maternal) body odor, providing strong support for multisensory inputs driving category acquisition in the developing human brain and having important implications for our understanding of human perceptual development.


Assuntos
Encéfalo/fisiologia , Mães , Odorantes , Atenção/fisiologia , Mapeamento Encefálico , Desenvolvimento Infantil/fisiologia , Reconhecimento Facial , Feminino , Humanos , Lactente , Masculino , Olfato/fisiologia
15.
Neuroimage Clin ; 24: 101987, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31446315

RESUMO

Variation in facial emotion processing abilities may contribute to variability in penetrance for psychotic symptoms in 22q11.2DS. However, the precise nature of the social cognitive dysfunction (i.e., facial expression perception vs. emotion recognition), the potential additional roles of genetic and environmental variabilities, and consequently the possibility of using this neurocognitive marker in clinical monitoring remain unclear. The present case study aimed at testing the hypothesis that when confounding factors are controlled, the presence of psychotic symptoms in 22q11.2DS is associated, at the individual level, with a neural marker of facial expression perception rather than explicit emotional face recognition. Two monozygotic twins with 22q11.2DS discordant for psychiatric manifestations performed (1) a classical facial emotion labelling task and (2) an implicit neural measurement of facial expression perception using a frequency-tagging approach in electroencephalography (EEG). Analysis of the periodic brain response elicited by a change of facial expression from neutrality indicated that the twin with psychotic symptoms did not detect emotion among neutral faces while the twin without the symptoms did. In contrast, both encountered difficulties labelling facial emotion. The results from this exploratory twin study support the idea that impaired facial expression perception rather than explicit recognition of the emotion expressed might be a neurocognitive endophenotype of psychotic symptoms that could be reliable at a clinical level. Although confirmatory studies should be required, it facilitates further discussion on the etiology of the clinical phenotype in 22q11.2DS.


Assuntos
Córtex Cerebral/fisiopatologia , Síndrome de DiGeorge/fisiopatologia , Emoções/fisiologia , Reconhecimento Facial/fisiologia , Transtornos Psicóticos/fisiopatologia , Percepção Social , Adulto , Biomarcadores , Síndrome de DiGeorge/complicações , Eletroencefalografia , Endofenótipos , Humanos , Masculino , Transtornos Psicóticos/etiologia , Gêmeos Monozigóticos , Adulto Jovem
16.
Neuropsychologia ; 129: 47-55, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30885642

RESUMO

Automatic responses to brief expression changes from a neutral face have been recently isolated in the human brain using fast periodic visual stimulation (FPVS) coupled with scalp electroencephalography (EEG). Based on these observations, here we isolate specific neural signatures for the rapid categorization of each of 5 basic expressions, i.e., when they are directly discriminated from all other facial expressions. Scalp EEG was recorded in 15 participants presented with pictures alternating at a rapid 6 Hz rate (i.e., one fixation/face, backward- and forward-masked). In different stimulation sequences, an expressive (angry, disgusted, happy, fearful, or sad) or a neutral face arose every 5 pictures (i.e., at 6/5 = 1.2 Hz), among pictures of the same individual expressing the other emotions randomly. Frequency-domain analysis indicated a robust (i.e., recorded in every individual participant) and objective (i.e., at the predefined 1.2 Hz frequency and its harmonics) expression-specific brain response over occipito-temporal sites for each emotion and neutrality. In this context of variable expressions, while neural responses to the different expressions (Anger, Disgust, Happiness, Sadness) were dissimilar qualitatively, a much larger specific signature for neutral faces as compared to facial expressions was found. Interestingly, Fear also elicited a strong contrasted response with other facial expressions, associated with a specific neural signature over ventral occipito-temporal sites. Collectively, these findings reveal that specific EEG signatures for different facial expressions can be isolated in the human brain, pointing to partially different neural substrates. In addition, they provide support for a strong and highly selective neural response to fear at the system-level, in line with the importance of this emotional expression for biological survival.


Assuntos
Córtex Cerebral/fisiologia , Discriminação Psicológica/fisiologia , Eletroencefalografia/métodos , Emoções/fisiologia , Expressão Facial , Reconhecimento Facial/fisiologia , Estimulação Luminosa/métodos , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
17.
Transl Psychiatry ; 9(1): 67, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30718458

RESUMO

Although various psychiatric disorders present with social-cognitive impairment, a measure assessing social-cognitive processes implicitly and reliably, with high selectivity and with enough signal-to-noise ratio (SNR) for individual evaluation of any population at any age, is lacking. Here we isolate a neural marker quantifying impaired visual coding of facial expression in individuals with 22q11.2 deletion syndrome (22q11DS) using frequency-tagging with electroencephalography (EEG). Twenty-two 22q11DS participants and 22 healthy controls were presented with changes of facial expression displayed at low, moderate, and high intensities every five cycles in a stream of one neutral face repeating 6 times per second (i.e., at a 6 Hz base rate). The brain response to expression changes tagged at the 1.2 Hz (i.e., 6 Hz/5) predefined frequency was isolated over occipito-temporal regions in both groups of participants for moderate- and high-intensity facial expressions. Neural sensitivity to facial expression was reduced by about 36% in 22q11DS, revealing impaired visual coding of emotional facial signals. The significance of the expression-change response was estimated for each single participant thanks to the high SNR of the approach. Further analyses revealed the high reliability of the response and its immunity from other neurocognitive skills. Interestingly, response magnitude was associated with the severity of positive symptoms, pointing to a potential endophenotype for psychosis risk. Overall, the present study reveals an objective, selective, reliable, and behavior-free signature of impaired visual coding of facial expression implicitly quantified from brain activity with high SNR. This novel tool opens avenues for clinical practice, providing a potential early biomarker for later psychosis onset and offering an alternative for individual assessment of social-cognitive functioning in even difficult-to-test participants.


Assuntos
Córtex Cerebral/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Síndrome de DiGeorge/fisiopatologia , Emoções/fisiologia , Expressão Facial , Reconhecimento Facial/fisiologia , Percepção Social , Adolescente , Adulto , Disfunção Cognitiva/etiologia , Síndrome de DiGeorge/complicações , Eletroencefalografia , Feminino , Humanos , Masculino , Adulto Jovem
18.
Neuropsychologia ; 122: 125-135, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30244000

RESUMO

This study examines the influence of social hierarchy on the neural electrophysiological responses to faces. In contrast with earlier EEG studies that typically manipulate social rank through competitive situations, we implemented hierarchy through occupational status and thus contrasted faces associated with high- vs. low-status (e.g. lawyer vs. waiter). Since social hierarchies are largely intertwined with gender, both female and male faces were used as stimuli, and both female and male participants were tested. The procedure consisted in presenting a status label before the face it was associated with. The analyses focused mainly on two components that have been shown to be modulated by competitive hierarchies and other social contexts, namely the N170 and the Late Positive Potential (LPP). The results indicated that gender, but not status, modulated the N170 amplitude. Moreover, high-status faces elicited larger LPP amplitude than low-status faces but this difference was driven by female participants. This gender effect is discussed in line with research showing that women and men are sensitive to different kinds of hierarchy. Methodological differences are considered to account for the discrepancy between studies that find an effect of hierarchy on the N170 and those that do not.


Assuntos
Encéfalo/fisiologia , Emprego , Reconhecimento Facial/fisiologia , Hierarquia Social , Percepção Social , Adulto , Associação , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Masculino , Caracteres Sexuais , Adulto Jovem
19.
Neuroimage ; 179: 235-251, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29913283

RESUMO

Efficient decoding of even brief and slight intensity facial expression changes is important for social interactions. However, robust evidence for the human brain ability to automatically detect brief and subtle changes of facial expression remains limited. Here we built on a recently developed paradigm in human electrophysiology with full-blown expressions (Dzhelyova et al., 2017), to isolate and quantify a neural marker for the detection of brief and subtle changes of facial expression. Scalp electroencephalogram (EEG) was recorded from 18 participants during stimulation of a neutral face changing randomly in size at a rapid rate of 6 Hz. Brief changes of expression appeared every five stimulation cycle (i.e., at 1.2 Hz) and expression intensity increased parametrically every 20 s in 20% steps during sweep sequences of 100 s. A significant 1.2 Hz response emerged in the EEG spectrum already at 40% of facial expression-change intensity for most of the 5 emotions tested (anger, disgust, fear, happiness, or sadness in different sequences), and increased with intensity steps, predominantly over right occipito-temporal regions. Given the high signal-to-noise ratio of the approach, thresholds for automatic detection of brief changes of facial expression could be determined for every single individual brain. A time-domain analysis revealed three components, the two first increasing linearly with increasing intensity as early as 100 ms after a change of expression, suggesting gradual low-level image-change detection prior to visual coding of facial movements. In contrast, the third component showed abrupt sensitivity to increasing expression intensity beyond 300 ms post expression-change, suggesting categorical emotion perception. Overall, this characterization of the detection of subtle changes of facial expression and its temporal dynamics open promising tracks for precise assessment of social perception ability during development and in clinical populations.


Assuntos
Encéfalo/fisiologia , Expressão Facial , Reconhecimento Visual de Modelos/fisiologia , Percepção Social , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Estimulação Luminosa , Adulto Jovem
20.
Cogn Emot ; 32(4): 827-842, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28776466

RESUMO

While there is an extensive literature on the tendency to mimic emotional expressions in adults, it is unclear how this skill emerges and develops over time. Specifically, it is unclear whether infants mimic discrete emotion-related facial actions, whether their facial displays are moderated by contextual cues and whether infants' emotional mimicry is constrained by developmental changes in the ability to discriminate emotions. We therefore investigate these questions using Baby-FACS to code infants' facial displays and eye-movement tracking to examine infants' looking times at facial expressions. Three-, 7-, and 12-month-old participants were exposed to dynamic facial expressions (joy, anger, fear, disgust, sadness) of a virtual model which either looked at the infant or had an averted gaze. Infants did not match emotion-specific facial actions shown by the model, but they produced valence-congruent facial responses to the distinct expressions. Furthermore, only the 7- and 12-month-olds displayed negative responses to the model's negative expressions and they looked more at areas of the face recruiting facial actions involved in specific expressions. Our results suggest that valence-congruent expressions emerge in infancy during a period where the decoding of facial expressions becomes increasingly sensitive to the social signal value of emotions.


Assuntos
Desenvolvimento Infantil/fisiologia , Emoções/fisiologia , Movimentos Oculares/fisiologia , Expressão Facial , Sinais (Psicologia) , Feminino , Humanos , Lactente , Masculino , Estimulação Luminosa
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