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Maffei A, Gambarota F, Liotti M, Dell'Acqua R, Tsuchiya N, Sessa P. Conscious perception of fear in faces: Insights from high-density EEG and perceptual awareness scale with threshold stimuli. Cortex 2024; 174:93-109. [PMID: 38493568 DOI: 10.1016/j.cortex.2024.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 10/12/2023] [Accepted: 02/08/2024] [Indexed: 03/19/2024]
Abstract
Contrary to the extensive research on processing subliminal and/or unattended emotional facial expressions, only a minority of studies have investigated the neural correlates of consciousness (NCCs) of emotions conveyed by faces. In the present high-density electroencephalography (EEG) study, we first employed a staircase procedure to identify each participant's perceptual threshold of the emotion expressed by the face and then compared the EEG signals elicited in trials where the participants were aware with the activity elicited in trials where participants were unaware of the emotions expressed by these, otherwise identical, faces. Drawing on existing knowledge of the neural mechanisms of face processing and NCCs, we hypothesized that activity in frontal electrodes would be modulated in relation to participants' awareness of facial emotional content. More specifically, we hypothesized that the NCC of fear seen on someone else's face could be detected as a modulation of a later and more anterior (i.e., at frontal sites) event-related potential (ERP) than the face-sensitive N170. By adopting a data-driven approach and cluster-based statistics to the analysis of EEG signals, the results were clear-cut in showing that visual awareness of fear was associated with the modulation of a frontal ERP component in a 150-300 msec interval. These insights are dissected and contextualized in relation to prevailing theories of visual consciousness and their proposed NCC benchmarks.
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Affiliation(s)
- Antonio Maffei
- Department of Developmental and Social Psychology (DPSS), University of Padova, Padova, Italy; Padova Neuroscience Center (PNC), University of Padova, Padova, Italy
| | - Filippo Gambarota
- Department of Developmental and Social Psychology (DPSS), University of Padova, Padova, Italy; Padova Neuroscience Center (PNC), University of Padova, Padova, Italy
| | - Mario Liotti
- Department of Developmental and Social Psychology (DPSS), University of Padova, Padova, Italy; Padova Neuroscience Center (PNC), University of Padova, Padova, Italy
| | - Roberto Dell'Acqua
- Department of Developmental and Social Psychology (DPSS), University of Padova, Padova, Italy; Padova Neuroscience Center (PNC), University of Padova, Padova, Italy
| | - Naotsugu Tsuchiya
- Turner Institute for Brain and Mental Health & School of Psychological Sciences, Faculty of Medicine, Nursing, and Health Sciences, Monash University, Melbourne, Victoria, Australia; Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology (NICT), Suita-shi, Osaka, Japan; Laboratory Head, Laboratory of Qualia Structure, ATR Computational Neuroscience Laboratories, Seika-cho, Soraku-gun, Kyoto, Japan.
| | - Paola Sessa
- Department of Developmental and Social Psychology (DPSS), University of Padova, Padova, Italy; Padova Neuroscience Center (PNC), University of Padova, Padova, Italy.
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2
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Weidner EM, Moratti S, Schindler S, Grewe P, Bien CG, Kissler J. Amygdala and cortical gamma-band responses to emotional faces are modulated by attention to valence. Psychophysiology 2024; 61:e14512. [PMID: 38174584 DOI: 10.1111/psyp.14512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 09/22/2023] [Accepted: 12/13/2023] [Indexed: 01/05/2024]
Abstract
The amygdala might support an attentional bias for emotional faces. However, whether and how selective attention toward a specific valence modulates this bias is not fully understood. Likewise, it is unclear whether amygdala and cortical signals respond to emotion and attention in a similar way. We recorded gamma-band activity (GBA, > 30 Hz) intracranially in the amygdalae of 11 patients with epilepsy and collected scalp recordings from 19 healthy participants. We presented angry, neutral, and happy faces randomly, and we denoted one valence as the target. Participants detected happy targets most quickly and accurately. In the amygdala, during attention to negative faces, low gamma-band activity (LGBA, < 90 Hz) increased for angry compared with happy faces from 160 ms. From 220 ms onward, amygdala high gamma-band activity (HGBA, > 90 Hz) was higher for angry and neutral faces than for happy ones. Monitoring neutral faces increased amygdala HGBA for emotions compared with neutral faces from 40 ms. Expressions were not differentiated in GBA while monitoring positive faces. On the scalp, only threat monitoring resulted in expression differentiation. Here, posterior LGBA was increased selectively for angry targets from 60 ms. The data show that GBA differentiation of emotional expressions is modulated by attention to valence: Top-down-controlled threat vigilance coordinates widespread GBA in favor of angry faces. Stimulus-driven emotion differentiation in amygdala GBA occurs during a neutral attentional focus. These findings align with a multi-pathway model of emotion processing and specify the role of GBA in this process.
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Affiliation(s)
- Enya M Weidner
- Department of Psychology, Bielefeld University, Bielefeld, Germany
| | - Stephan Moratti
- Department of Experimental Psychology, Complutense University of Madrid, Madrid, Spain
| | - Sebastian Schindler
- Institute of Medical Psychology and Systems Neuroscience, University of Münster, Münster, Germany
| | - Philip Grewe
- Deptartment of Epileptology, Krankenhaus Mara, Bethel Epilepsy Center, Medical School OWL, Bielefeld University, Bielefeld, Germany
- Clinical Neuropsychology and Epilepsy Research, Medical School OWL, Bielefeld University, Bielefeld, Germany
| | - Christian G Bien
- Deptartment of Epileptology, Krankenhaus Mara, Bethel Epilepsy Center, Medical School OWL, Bielefeld University, Bielefeld, Germany
| | - Johanna Kissler
- Department of Psychology, Bielefeld University, Bielefeld, Germany
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3
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Chang S, He L, Jiang R, Zhang X, Meng M. Unconscious face processing shows a different lateralisation pattern. Psychon Bull Rev 2024; 31:649-658. [PMID: 37653278 DOI: 10.3758/s13423-023-02367-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/09/2023] [Indexed: 09/02/2023]
Abstract
Faces contain rich information and play a pivotal role in human daily social interactions. Previous studies have provided evidence for the left-visual-field-advantage in face perception. The current study investigated lateralisation when face stimuli were unconsciously presented using interocular suppression methods. The results showed that when an unconscious face stimulus was presented in one side of the visual field without other face stimuli, the unconscious face in the right visual field could break through interocular suppression faster than that in the left (Experiments 1 and 2). However, this right visual field processing advantage reversed to the left when a face stimulus either with (Experiment 2) or without (Experiment 3) visual awareness was presented concurrently with or prior to (Experiment 4) the unconscious face stimuli. These results showed that the unconscious face might have a different processing pattern compared with the conscious face. The relationship between this novel behavioural observation and known functional lateralisation of the fusiform face areas is discussed, suggesting a dynamic interaction between the two cortical hemispheres may underlie the formation of visual awareness for faces. The current study expands our understanding of face processing lateralisation and provided evidence on the asymmetric inter-hemisphere interaction patterns in forming visual awareness.
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Affiliation(s)
- Shuai Chang
- Philosophy and Social Science Laboratory of Reading and Development in Children and Adolescents (South China Normal University), Ministry of Education, Guangzhou, China
- Guangdong Key Laboratory of Mental Health and Cognitive Science, School of Psychology, South China Normal University, Guangzhou, China
| | - Ling He
- Philosophy and Social Science Laboratory of Reading and Development in Children and Adolescents (South China Normal University), Ministry of Education, Guangzhou, China
- Guangdong Key Laboratory of Mental Health and Cognitive Science, School of Psychology, South China Normal University, Guangzhou, China
| | - Rong Jiang
- Philosophy and Social Science Laboratory of Reading and Development in Children and Adolescents (South China Normal University), Ministry of Education, Guangzhou, China
- Guangdong Key Laboratory of Mental Health and Cognitive Science, School of Psychology, South China Normal University, Guangzhou, China
| | - Xinyu Zhang
- Philosophy and Social Science Laboratory of Reading and Development in Children and Adolescents (South China Normal University), Ministry of Education, Guangzhou, China
- Guangdong Key Laboratory of Mental Health and Cognitive Science, School of Psychology, South China Normal University, Guangzhou, China
| | - Ming Meng
- Philosophy and Social Science Laboratory of Reading and Development in Children and Adolescents (South China Normal University), Ministry of Education, Guangzhou, China.
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Sato W, Yoshikawa S. Influence of stimulus manipulation on conscious awareness of emotional facial expressions in the match-to-sample paradigm. Sci Rep 2023; 13:20727. [PMID: 38007578 PMCID: PMC10676436 DOI: 10.1038/s41598-023-47995-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 11/21/2023] [Indexed: 11/27/2023] Open
Abstract
The conscious perception of emotional facial expressions plays an indispensable role in social interaction. However, previous psychological studies have reported inconsistent findings regarding whether conscious awareness is greater for emotional expressions than for neutral expressions. Furthermore, whether this phenomenon is attributable to emotional or visual factors remains unknown. To investigate these issues, we conducted five psychological experiments to test the conscious perception of emotional and neutral facial expressions using the match-to-sample paradigm. Facial stimuli were momentarily presented in the peripheral visual fields while participants read simultaneously presented letters in the central visual fields. The participants selected a perceived face from nine samples. The results of all experiments demonstrated that emotional expressions were more accurately identified than neutral expressions. Furthermore, Experiment 4 showed that angry expressions were identified more accurately than anti-angry expressions, which expressed neutral emotions with comparable physical changes to angry expressions. Experiment 5, testing the interaction between emotional expression and face direction, showed that angry expressions looking toward participants were more accurately identified than those looking away from participants, even though they were physically identical. These results suggest that the conscious awareness of emotional facial expressions is enhanced by their emotional significance.
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Affiliation(s)
- Wataru Sato
- Psychological Process Research Team, Guardian Robot Project, RIKEN, 2-2-2 Hikaridai, Seika-cho, Soraku-gun, Kyoto, 619-0288, Japan.
- Field Science Education and Research Center, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo, Kyoto, 606-8502, Japan.
| | - Sakiko Yoshikawa
- Field Science Education and Research Center, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo, Kyoto, 606-8502, Japan
- Faculty of the Arts, Kyoto University of the Arts, 2-116 Uryuyama, Kitashirakawa, Sakyo, Kyoto, 606-8501, Japan
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5
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Qiu Z, Becker SI, Xia H, Hamblin-Frohman Z, Pegna AJ. Fixation-related electrical potentials during a free visual search task reveal the timing of visual awareness. iScience 2023; 26:107148. [PMID: 37408689 PMCID: PMC10319232 DOI: 10.1016/j.isci.2023.107148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 04/26/2023] [Accepted: 06/12/2023] [Indexed: 07/07/2023] Open
Abstract
It has been repeatedly claimed that emotional faces readily capture attention, and that they may be processed without awareness. Yet some observations cast doubt on these assertions. Part of the problem may lie in the experimental paradigms employed. Here, we used a free viewing visual search task during electroencephalographic recordings, where participants searched for either fearful or neutral facial expressions among distractor expressions. Fixation-related potentials were computed for fearful and neutral targets and the response compared for stimuli consciously reported or not. We showed that awareness was associated with an electrophysiological negativity starting at around 110 ms, while emotional expressions were distinguished on the N170 and early posterior negativity only when stimuli were consciously reported. These results suggest that during unconstrained visual search, the earliest electrical correlate of awareness may emerge as early as 110 ms, and fixating at an emotional face without reporting it may not produce any unconscious processing.
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Affiliation(s)
- Zeguo Qiu
- School of Psychology, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Stefanie I. Becker
- School of Psychology, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Hongfeng Xia
- School of Psychology, The University of Queensland, Brisbane, QLD 4072, Australia
| | | | - Alan J. Pegna
- School of Psychology, The University of Queensland, Brisbane, QLD 4072, Australia
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Lim C, Inagaki M, Shinozaki T, Fujita I. Analysis of convolutional neural networks reveals the computational properties essential for subcortical processing of facial expression. Sci Rep 2023; 13:10908. [PMID: 37407668 DOI: 10.1038/s41598-023-37995-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 06/30/2023] [Indexed: 07/07/2023] Open
Abstract
Perception of facial expression is crucial for primate social interactions. This visual information is processed through the ventral cortical pathway and the subcortical pathway. However, the subcortical pathway exhibits inaccurate processing, and the responsible architectural and physiological properties remain unclear. To investigate this, we constructed and examined convolutional neural networks with three key properties of the subcortical pathway: a shallow layer architecture, concentric receptive fields at the initial processing stage, and a greater degree of spatial pooling. These neural networks achieved modest accuracy in classifying facial expressions. By replacing these properties, individually or in combination, with corresponding cortical features, performance gradually improved. Similar to amygdala neurons, some units in the final processing layer exhibited sensitivity to retina-based spatial frequencies (SFs), while others were sensitive to object-based SFs. Replacement of any of these properties affected the coordinates of the SF encoding. Therefore, all three properties limit the accuracy of facial expression information and are essential for determining the SF representation coordinate. These findings characterize the role of the subcortical computational processes in facial expression recognition.
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Affiliation(s)
- Chanseok Lim
- Laboratory for Cognitive Neuroscience, Graduate School of Frontier Biosciences, Osaka University, 1-4 Yamadaoka, Suita, Osaka, 565-0871, Japan
- Perceptual and Cognitive Neuroscience Laboratory, Graduate School of Frontier Biosciences, Osaka University, 1-4 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Mikio Inagaki
- Laboratory for Cognitive Neuroscience, Graduate School of Frontier Biosciences, Osaka University, 1-4 Yamadaoka, Suita, Osaka, 565-0871, Japan
- Center for Information and Neural Networks, National Institute of Information and Communications Technology, 1-4 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Takashi Shinozaki
- Center for Information and Neural Networks, National Institute of Information and Communications Technology, 1-4 Yamadaoka, Suita, Osaka, 565-0871, Japan
- Computational Neuroscience Laboratory, Faculty of Informatics, Kindai University, 3-4-1 Kowakae, Higashiosaka, Osaka, 577-8502, Japan
| | - Ichiro Fujita
- Laboratory for Cognitive Neuroscience, Graduate School of Frontier Biosciences, Osaka University, 1-4 Yamadaoka, Suita, Osaka, 565-0871, Japan.
- Center for Information and Neural Networks, National Institute of Information and Communications Technology, 1-4 Yamadaoka, Suita, Osaka, 565-0871, Japan.
- Research Organization of Science and Technology, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga, 525-8577, Japan.
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Klingner CM, Guntinas-Lichius O. Facial expression and emotion. Laryngorhinootologie 2023; 102:S115-S125. [PMID: 37130535 PMCID: PMC10171334 DOI: 10.1055/a-2003-5687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Human facial expressions are unique in their ability to express our emotions and communicate them to others. The mimic expression of basic emotions is very similar across different cultures and has also many features in common with other mammals. This suggests a common genetic origin of the association between facial expressions and emotion. However, recent studies also show cultural influences and differences. The recognition of emotions from facial expressions, as well as the process of expressing one's emotions facially, occurs within an extremely complex cerebral network. Due to the complexity of the cerebral processing system, there are a variety of neurological and psychiatric disorders that can significantly disrupt the coupling of facial expressions and emotions. Wearing masks also limits our ability to convey and recognize emotions through facial expressions. Through facial expressions, however, not only "real" emotions can be expressed, but also acted ones. Thus, facial expressions open up the possibility of faking socially desired expressions and also of consciously faking emotions. However, these pretenses are mostly imperfect and can be accompanied by short-term facial movements that indicate the emotions that are actually present (microexpressions). These microexpressions are of very short duration and often barely perceptible by humans, but they are the ideal application area for computer-aided analysis. This automatic identification of microexpressions has not only received scientific attention in recent years, but its use is also being tested in security-related areas. This article summarizes the current state of knowledge of facial expressions and emotions.
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Affiliation(s)
- Carsten M Klingner
- Hans Berger Department of Neurology, Jena University Hospital, Germany
- Biomagnetic Center, Jena University Hospital, Germany
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8
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Effects of spatially filtered fearful faces and awareness on amygdala activity in adults with autism spectrum disorder: A magnetoencephalography study. Neurosci Lett 2023; 800:137135. [PMID: 36804074 DOI: 10.1016/j.neulet.2023.137135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Revised: 01/29/2023] [Accepted: 02/15/2023] [Indexed: 02/19/2023]
Abstract
BACKGROUND The amygdala is pivotal in emotional face processing. Spatial frequencies (SFs) of visual images are divided and processed via two visual pathways: low spatial frequency (LSF) information is conveyed by the magnocellular pathway, while the parvocellular pathway carries high spatial frequency information. We hypothesized that altered amygdala activity might underlie atypical social communication caused by changes in both conscious and non-conscious emotional face processing in the brain in individuals with autism spectrum disorder (ASD). METHOD Eighteen adults with ASD and 18 typically developing (TD) peers participated in this study. Spatially filtered fearful- and neutral-expression faces and object stimuli were presented under supraliminal or subliminal conditions, and neuromagnetic responses in the amygdala were measured using 306-channel whole-head magnetoencephalography. RESULTS The latency of the evoked responses at approximately 200 ms to unfiltered neutral face stimuli and object stimuli in the ASD group was shorter than that in the TD group in the unaware condition. Regarding emotional face processing, the evoked responses in the ASD group were larger than those in the TD group under the aware condition. The later positive shift during 200-500 ms (ARV) was larger than that in the TD group, regardless of awareness. Moreover, ARV to HSF face stimuli was larger than that to the other spatial filtered face stimuli in the aware condition. CONCLUSION Regardless of awareness, ARV might reflect atypical face information processing in the ASD brain.
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Cushing CA, Dawes AJ, Hofmann SG, Lau H, LeDoux JE, Taschereau-Dumouchel V. A generative adversarial model of intrusive imagery in the human brain. PNAS NEXUS 2023; 2:pgac265. [PMID: 36733294 PMCID: PMC9887942 DOI: 10.1093/pnasnexus/pgac265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 01/20/2023] [Indexed: 01/24/2023]
Abstract
The mechanisms underlying the subjective experiences of mental disorders remain poorly understood. This is partly due to long-standing over-emphasis on behavioral and physiological symptoms and a de-emphasis of the patient's subjective experiences when searching for treatments. Here, we provide a new perspective on the subjective experience of mental disorders based on findings in neuroscience and artificial intelligence (AI). Specifically, we propose the subjective experience that occurs in visual imagination depends on mechanisms similar to generative adversarial networks that have recently been developed in AI. The basic idea is that a generator network fabricates a prediction of the world, and a discriminator network determines whether it is likely real or not. Given that similar adversarial interactions occur in the two major visual pathways of perception in people, we explored whether we could leverage this AI-inspired approach to better understand the intrusive imagery experiences of patients suffering from mental illnesses such as post-traumatic stress disorder (PTSD) and acute stress disorder. In our model, a nonconscious visual pathway generates predictions of the environment that influence the parallel but interacting conscious pathway. We propose that in some patients, an imbalance in these adversarial interactions leads to an overrepresentation of disturbing content relative to current reality, and results in debilitating flashbacks. By situating the subjective experience of intrusive visual imagery in the adversarial interaction of these visual pathways, we propose testable hypotheses on novel mechanisms and clinical applications for controlling and possibly preventing symptoms resulting from intrusive imagery.
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Affiliation(s)
- Cody A Cushing
- Department of Psychology, UCLA, Los Angeles, CA, 90095, USA
| | - Alexei J Dawes
- RIKEN Center for Brain Science, Wako, Saitama 351-0106, Japan
| | - Stefan G Hofmann
- Department of Clinical Psychology, Philipps-University Marburg, 35037 Marburg, Germany
- Department of Psychological and Brain Sciences, Boston University, Boston, MA, 02215, USA
| | - Hakwan Lau
- RIKEN Center for Brain Science, Wako, Saitama 351-0106, Japan
| | - Joseph E LeDoux
- Center for Neural Science and Department of Psychology, New York University, New York, NY, 10012, USA
- Department of Psychiatry, and Department of Child and Adolescent Psychiatry, New York University Langone Medical School, New York, NY, 10016, USA
| | - Vincent Taschereau-Dumouchel
- Department of Psychiatry and Addictology, Université de Montréal, Montreal, Quebec H3T 1J4, Canada
- Centre de Recherche de l'Institut Universitaire en Santé Mentale de Montréal, Montreal, Quebec H1N 3M5, Canada
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10
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Méndez CA, Celeghin A, Diano M, Orsenigo D, Ocak B, Tamietto M. A deep neural network model of the primate superior colliculus for emotion recognition. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210512. [PMID: 36126660 PMCID: PMC9489290 DOI: 10.1098/rstb.2021.0512] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Although sensory processing is pivotal to nearly every theory of emotion, the evaluation of the visual input as ‘emotional’ (e.g. a smile as signalling happiness) has been traditionally assumed to take place in supramodal ‘limbic’ brain regions. Accordingly, subcortical structures of ancient evolutionary origin that receive direct input from the retina, such as the superior colliculus (SC), are traditionally conceptualized as passive relay centres. However, mounting evidence suggests that the SC is endowed with the necessary infrastructure and computational capabilities for the innate recognition and initial categorization of emotionally salient features from retinal information. Here, we built a neurobiologically inspired convolutional deep neural network (DNN) model that approximates physiological, anatomical and connectional properties of the retino-collicular circuit. This enabled us to characterize and isolate the initial computations and discriminations that the DNN model of the SC can perform on facial expressions, based uniquely on the information it directly receives from the virtual retina. Trained to discriminate facial expressions of basic emotions, our model matches human error patterns and above chance, yet suboptimal, classification accuracy analogous to that reported in patients with V1 damage, who rely on retino-collicular pathways for non-conscious vision of emotional attributes. When presented with gratings of different spatial frequencies and orientations never ‘seen’ before, the SC model exhibits spontaneous tuning to low spatial frequencies and reduced orientation discrimination, as can be expected from the prevalence of the magnocellular (M) over parvocellular (P) projections. Likewise, face manipulation that biases processing towards the M or P pathway affects expression recognition in the SC model accordingly, an effect that dovetails with variations of activity in the human SC purposely measured with ultra-high field functional magnetic resonance imaging. Lastly, the DNN generates saliency maps and extracts visual features, demonstrating that certain face parts, like the mouth or the eyes, provide higher discriminative information than other parts as a function of emotional expressions like happiness and sadness. The present findings support the contention that the SC possesses the necessary infrastructure to analyse the visual features that define facial emotional stimuli also without additional processing stages in the visual cortex or in ‘limbic’ areas. This article is part of the theme issue ‘Cracking the laugh code: laughter through the lens of biology, psychology and neuroscience’.
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Affiliation(s)
- Carlos Andrés Méndez
- Department of Psychology, University of Torino, Via Verdi 10, Torino 10124, Italy
| | - Alessia Celeghin
- Department of Psychology, University of Torino, Via Verdi 10, Torino 10124, Italy
| | - Matteo Diano
- Department of Psychology, University of Torino, Via Verdi 10, Torino 10124, Italy
| | - Davide Orsenigo
- Department of Psychology, University of Torino, Via Verdi 10, Torino 10124, Italy
| | - Brian Ocak
- Department of Psychology, University of Torino, Via Verdi 10, Torino 10124, Italy.,Section of Cognitive Neurophysiology and Imaging, National Institute of Mental Health, 49 Convent Drive, Bethesda, MD 20892, USA
| | - Marco Tamietto
- Department of Psychology, University of Torino, Via Verdi 10, Torino 10124, Italy.,Department of Medical and Clinical Psychology, and CoRPS - Center of Research on Psychology in Somatic diseases, Tilburg University, PO Box 90153, 5000 LE Tilburg, The Netherlands
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11
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Qiu Z, Lei X, Becker SI, Pegna AJ. Neural activities during the Processing of unattended and unseen emotional faces: a voxel-wise Meta-analysis. Brain Imaging Behav 2022; 16:2426-2443. [PMID: 35739373 PMCID: PMC9581832 DOI: 10.1007/s11682-022-00697-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/03/2022] [Indexed: 11/27/2022]
Abstract
Voxel-wise meta-analyses of task-evoked regional activity were conducted for healthy individuals during the unconscious processing of emotional and neutral faces with an aim to examine whether and how different experimental paradigms influenced brain activation patterns. Studies were categorized into sensory and attentional unawareness paradigms. Thirty-four fMRI studies including 883 healthy participants were identified. Across experimental paradigms, unaware emotional faces elicited stronger activation of the limbic system, striatum, inferior frontal gyrus, insula and the temporal lobe, compared to unaware neutral faces. Crucially, in attentional unawareness paradigms, unattended emotional faces elicited a right-lateralized increased activation (i.e., right amygdala, right temporal pole), suggesting a right hemisphere dominance for processing emotional faces during inattention. By contrast, in sensory unawareness paradigms, unseen emotional faces elicited increased activation of the left striatum, the left amygdala and the right middle temporal gyrus. Additionally, across paradigms, unconsciously processed positive emotions were found associated with more activation in temporal and parietal cortices whereas unconsciously processed negative emotions elicited stronger activation in subcortical regions, compared to neutral faces.
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Affiliation(s)
- Zeguo Qiu
- School of Psychology, The University of Queensland, Brisbane, 4072, Australia.
| | - Xue Lei
- School of Psychology, The University of Queensland, Brisbane, 4072, Australia
| | - Stefanie I Becker
- School of Psychology, The University of Queensland, Brisbane, 4072, Australia
| | - Alan J Pegna
- School of Psychology, The University of Queensland, Brisbane, 4072, Australia
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12
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Cautionary Observations Concerning the Introduction of Psychophysiological Biomarkers into Neuropsychiatric Practice. PSYCHIATRY INTERNATIONAL 2022. [DOI: 10.3390/psychiatryint3020015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The combination of statistical learning technologies with large databases of psychophysiological data has appropriately generated enthusiastic interest in future clinical applicability. It is argued here that this enthusiasm should be tempered with the understanding that significant obstacles must be overcome before the systematic introduction of psychophysiological measures into neuropsychiatric practice becomes possible. The objective of this study is to identify challenges to this effort. The nonspecificity of psychophysiological measures complicates their use in diagnosis. Low test-retest reliability complicates use in longitudinal assessment, and quantitative psychophysiological measures can normalize in response to placebo intervention. Ten cautionary observations are introduced and, in some instances, possible directions for remediation are suggested.
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13
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Baier D, Kempkes M, Ditye T, Ansorge U. Do Subliminal Fearful Facial Expressions Capture Attention? Front Psychol 2022; 13:840746. [PMID: 35496171 PMCID: PMC9039161 DOI: 10.3389/fpsyg.2022.840746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 03/22/2022] [Indexed: 11/29/2022] Open
Abstract
In two experiments, we tested whether fearful facial expressions capture attention in an awareness-independent fashion. In Experiment 1, participants searched for a visible neutral face presented at one of two positions. Prior to the target, a backward-masked and, thus, invisible emotional (fearful/disgusted) or neutral face was presented as a cue, either at target position or away from the target position. If negative emotional faces capture attention in a stimulus-driven way, we would have expected a cueing effect: better performance where fearful or disgusted facial cues were presented at target position than away from the target. However, no evidence of capture of attention was found, neither in behavior (response times or error rates), nor in event-related lateralizations (N2pc). In Experiment 2, we went one step further and used fearful faces as visible targets, too. Thereby, we sought to boost awareness-independent capture of attention by fearful faces. However, still, we found no significant attention-capture effect. Our results show that fearful facial expressions do not capture attention in an awareness-independent way. Results are discussed in light of existing theories.
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Affiliation(s)
- Diane Baier
- Faculty of Psychology, University of Vienna, Vienna, Austria.,Acoustics Research Institute, Austrian Academy of Sciences, Vienna, Austria
| | - Marleen Kempkes
- Faculty of Psychology, University of Vienna, Vienna, Austria
| | - Thomas Ditye
- Faculty of Psychology, University of Vienna, Vienna, Austria.,Faculty of Psychology, Sigmund Freud University, Vienna, Austria
| | - Ulrich Ansorge
- Faculty of Psychology, University of Vienna, Vienna, Austria.,Cognitive Science Hub, University of Vienna, Vienna, Austria
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14
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Inagaki M, Inoue KI, Tanabe S, Kimura K, Takada M, Fujita I. Rapid processing of threatening faces in the amygdala of nonhuman primates: subcortical inputs and dual roles. Cereb Cortex 2022; 33:895-915. [PMID: 35323915 PMCID: PMC9890477 DOI: 10.1093/cercor/bhac109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 02/22/2022] [Accepted: 02/22/2022] [Indexed: 02/04/2023] Open
Abstract
A subcortical pathway through the superior colliculus and pulvinar has been proposed to provide the amygdala with rapid but coarse visual information about emotional faces. However, evidence for short-latency, facial expression-discriminating responses from individual amygdala neurons is lacking; even if such a response exists, how it might contribute to stimulus detection is unclear. Also, no definitive anatomical evidence is available for the assumed pathway. Here we showed that ensemble responses of amygdala neurons in monkeys carried robust information about open-mouthed, presumably threatening, faces within 50 ms after stimulus onset. This short-latency signal was not found in the visual cortex, suggesting a subcortical origin. Temporal analysis revealed that the early response contained excitatory and suppressive components. The excitatory component may be useful for sending rapid signals downstream, while the sharpening of the rising phase of later-arriving inputs (presumably from the cortex) by the suppressive component might improve the processing of facial expressions over time. Injection of a retrograde trans-synaptic tracer into the amygdala revealed presumed monosynaptic labeling in the pulvinar and disynaptic labeling in the superior colliculus, including the retinorecipient layers. We suggest that the early amygdala responses originating from the colliculo-pulvino-amygdalar pathway play dual roles in threat detection.
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Affiliation(s)
- Mikio Inagaki
- Laboratory for Cognitive Neuroscience, Graduate School of Frontier Biosciences, Osaka University, 1-4 Yamadaoka, Suita, Osaka 565-0871, Japan,Center for Information and Neural Networks, National Institute of Information and Communications Technology and Osaka University, 1-4 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Ken-ichi Inoue
- Systems Neuroscience Section, Primate Research Institute, Kyoto University, 41-2 Kanrin, Inuyama, Aichi 484-8506, Japan
| | - Soshi Tanabe
- Systems Neuroscience Section, Primate Research Institute, Kyoto University, 41-2 Kanrin, Inuyama, Aichi 484-8506, Japan
| | - Kei Kimura
- Systems Neuroscience Section, Primate Research Institute, Kyoto University, 41-2 Kanrin, Inuyama, Aichi 484-8506, Japan
| | - Masahiko Takada
- Systems Neuroscience Section, Primate Research Institute, Kyoto University, 41-2 Kanrin, Inuyama, Aichi 484-8506, Japan
| | - Ichiro Fujita
- Corresponding author: Laboratory for Cognitive Neuroscience, Graduate School of Frontier Biosciences, Osaka University, 1-4 Yamadaoka, Suita, Osaka 565-0871, Japan.
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15
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Rehabilitation of visual perception in cortical blindness. HANDBOOK OF CLINICAL NEUROLOGY 2022; 184:357-373. [PMID: 35034749 DOI: 10.1016/b978-0-12-819410-2.00030-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Blindness is a common sequela after stroke affecting the primary visual cortex, presenting as a contralesional, homonymous, visual field cut. This can occur unilaterally or, less commonly, bilaterally. While it has been widely assumed that after a brief period of spontaneous improvement, vision loss becomes stable and permanent, accumulating data show that visual training can recover some of the vision loss, even long after the stroke. Here, we review the different approaches to rehabilitation employed in adult-onset cortical blindness (CB), focusing on visual restoration methods. Most of this work was conducted in chronic stroke patients, partially restoring visual discrimination and luminance detection. However, to achieve this, patients had to train for extended periods (usually many months), and the vision restored was not entirely normal. Several adjuvants to training such as noninvasive, transcranial brain stimulation, and pharmacology are starting to be investigated for their potential to increase the efficacy of training in CB patients. However, these approaches are still exploratory and require considerably more research before being adopted. Nonetheless, having established that the adult visual system retains the capacity for restorative plasticity, attention recently turned toward the subacute poststroke period. Drawing inspiration from sensorimotor stroke rehabilitation, visual training was recently attempted for the first time in subacute poststroke patients. It improved vision faster, over larger portions of the blind field, and for a larger number of visual discrimination abilities than identical training initiated more than 6 months poststroke (i.e., in the chronic period). In conclusion, evidence now suggests that visual neuroplasticity after occipital stroke can be reliably recruited by a range of visual training approaches. In addition, it appears that poststroke visual plasticity is dynamic, with a critical window of opportunity in the early postdamage period to attain more rapid, more extensive recovery of a larger set of visual perceptual abilities.
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16
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Domínguez-Borràs J, Vuilleumier P. Amygdala function in emotion, cognition, and behavior. HANDBOOK OF CLINICAL NEUROLOGY 2022; 187:359-380. [PMID: 35964983 DOI: 10.1016/b978-0-12-823493-8.00015-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The amygdala is a core structure in the anterior medial temporal lobe, with an important role in several brain functions involving memory, emotion, perception, social cognition, and even awareness. As a key brain structure for saliency detection, it triggers and controls widespread modulatory signals onto multiple areas of the brain, with a great impact on numerous aspects of adaptive behavior. Here we discuss the neural mechanisms underlying these functions, as established by animal and human research, including insights provided in both healthy and pathological conditions.
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Affiliation(s)
- Judith Domínguez-Borràs
- Department of Clinical Psychology and Psychobiology & Institute of Neurosciences, University of Barcelona, Barcelona, Spain
| | - Patrik Vuilleumier
- Department of Neuroscience and Center for Affective Sciences, University of Geneva, Geneva, Switzerland.
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17
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Right Hemisphere Dominance for Unconscious Emotionally Salient Stimuli. Brain Sci 2021; 11:brainsci11070823. [PMID: 34206214 PMCID: PMC8301990 DOI: 10.3390/brainsci11070823] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 06/13/2021] [Accepted: 06/18/2021] [Indexed: 12/30/2022] Open
Abstract
The present review will focus on evidence demonstrating the prioritization in visual processing of fear-related signals in the absence of awareness. Evidence in hemianopic patients without any form of blindsight or affective blindsight in classical terms will be presented, demonstrating that fearful faces, via a subcortical colliculo-pulvinar-amygdala pathway, have a privileged unconscious visual processing and facilitate responses towards visual stimuli in the intact visual field. Interestingly, this fear-specific implicit visual processing in hemianopics has only been observed after lesions to the visual cortices in the left hemisphere, while no effect was found in patients with damage to the right hemisphere. This suggests that the subcortical route for emotional processing in the right hemisphere might provide a pivotal contribution to the implicit processing of fear, in line with evidence showing enhanced right amygdala activity and increased connectivity in the right colliculo-pulvinar-amygdala pathway for unconscious fear-conditioned stimuli and subliminal fearful faces. These findings will be discussed within a theoretical framework that considers the amygdala as an integral component of a constant and continuous vigilance system, which is preferentially invoked with stimuli signaling ambiguous environmental situations of biological relevance, such as fearful faces.
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18
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Isa T, Yoshida M. Neural Mechanism of Blindsight in a Macaque Model. Neuroscience 2021; 469:138-161. [PMID: 34153356 DOI: 10.1016/j.neuroscience.2021.06.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 06/09/2021] [Accepted: 06/14/2021] [Indexed: 11/15/2022]
Abstract
Some patients with damage to the primary visual cortex (V1) exhibit visuomotor ability, despite loss of visual awareness, a phenomenon termed "blindsight". We review a series of studies conducted mainly in our laboratory on macaque monkeys with unilateral V1 lesioning to reveal the neural pathways underlying visuomotor transformation and the cognitive capabilities retained in blindsight. After lesioning, it takes several weeks for the recovery of visually guided saccades toward the lesion-affected visual field. In addition to the lateral geniculate nucleus, the pathway from the superior colliculus to the pulvinar participates in visuomotor processing in blindsight. At the cortical level, bilateral lateral intraparietal regions become critically involved in the saccade control. These results suggest that the visual circuits experience drastic changes while the monkey acquires blindsight. In these animals, analysis based on signal detection theory adapted to behavior in the "Yes-No" task indicates reduced sensitivity to visual targets, suggesting that visual awareness is impaired. Saccades become less accurate, decisions become less deliberate, and some forms of bottom-up attention are impaired. However, a variety of cognitive functions are retained such as saliency detection during free viewing, top-down attention, short-term spatial memory, and associative learning. These observations indicate that blindsight is not a low-level sensory-motor response, but the residual visual inputs can access these cognitive capabilities. Based on these results we suggest that the macaque model of blindsight replicates type II blindsight patients who experience some "feeling" of objects, which guides cognitive capabilities that we naïvely think are not possible without phenomenal consciousness.
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Affiliation(s)
- Tadashi Isa
- Department of Neuroscience, Graduate School of Medicine, Kyoto University, Yoshida-konoe-cho, Sakyo-ku, Kyoto, 606-8501, Japan; Institute for the Advanced Study of Human Biology (WPI-ASHBi), Kyoto University, Yoshida-konoe-cho, Sakyo-ku, Kyoto, 606-8501, Japan; Human Brain Research Center, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan
| | - Masatoshi Yoshida
- Center for Human Nature, Artificial Intelligence, and Neuroscience (CHAIN), Hokkaido University, Sapporo, 060-0812, Japan
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19
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Is the primary visual cortex necessary for blindsight-like behavior? Review of transcranial magnetic stimulation studies in neurologically healthy individuals. Neurosci Biobehav Rev 2021; 127:353-364. [PMID: 33965459 DOI: 10.1016/j.neubiorev.2021.04.038] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 04/28/2021] [Accepted: 04/29/2021] [Indexed: 12/20/2022]
Abstract
The visual pathways that bypass the primary visual cortex (V1) are often assumed to support visually guided behavior in humans in the absence of conscious vision. This conclusion is largely based on findings on patients: V1 lesions cause blindness but sometimes leave some visually guided behaviors intact-this is known as blindsight. With the aim of examining how well the findings on blindsight patients generalize to neurologically healthy individuals, we review studies which have tried to uncover transcranial magnetic stimulation (TMS) induced blindsight. In general, these studies have failed to demonstrate a completely unconscious blindsight-like capacity in neurologically healthy individuals. A possible exception to this is TMS-induced blindsight of stimulus presence or location. Because blindsight in patients is often associated with some form of introspective access to the visual stimulus, and blindsight may be associated with neural reorganization, we suggest that rather than revealing a dissociation between visually guided behavior and conscious seeing, blindsight may reflect preservation or partial recovery of conscious visual perception after the lesion.
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20
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Abbas A, Chalup S. Affective analysis of visual scenes using face pareidolia and scene-context. Neurocomputing 2021. [DOI: 10.1016/j.neucom.2021.01.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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21
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The impact of facemasks on emotion recognition, trust attribution and re-identification. Sci Rep 2021; 11:5577. [PMID: 33692417 PMCID: PMC7970937 DOI: 10.1038/s41598-021-84806-5] [Citation(s) in RCA: 97] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 02/19/2021] [Indexed: 01/02/2023] Open
Abstract
Covid-19 pandemics has fostered a pervasive use of facemasks all around the world. While they help in preventing infection, there are concerns related to the possible impact of facemasks on social communication. The present study investigates how emotion recognition, trust attribution and re-identification of faces differ when faces are seen without mask, with a standard medical facemask, and with a transparent facemask restoring visual access to the mouth region. Our results show that, in contrast to standard medical facemasks, transparent masks significantly spare the capability to recognize emotional expressions. Moreover, transparent masks spare the capability to infer trustworthiness from faces with respect to standard medical facemasks which, in turn, dampen the perceived untrustworthiness of faces. Remarkably, while transparent masks (unlike standard masks) do not impair emotion recognition and trust attribution, they seemingly do impair the subsequent re-identification of the same, unmasked, face (like standard masks). Taken together, this evidence supports a dissociation between mechanisms sustaining emotion and identity processing. This study represents a pivotal step in the much-needed analysis of face reading when the lower portion of the face is occluded by a facemask.
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22
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Wang MY, Yuan Z. EEG Decoding of Dynamic Facial Expressions of Emotion: Evidence from SSVEP and Causal Cortical Network Dynamics. Neuroscience 2021; 459:50-58. [PMID: 33556458 DOI: 10.1016/j.neuroscience.2021.01.040] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 01/14/2021] [Accepted: 01/31/2021] [Indexed: 01/23/2023]
Abstract
The neural cognitive mechanism in processing static facial expressions (FEs) has been well documented, whereas the one underlying perceiving dynamic faces remains unclear. In this study, Fourier transformation and time-frequency analysis of Electroencephalography (EEG) data were carried out to detect the brain activation underlying dynamic or static FEs while twenty-one participants were viewing dynamic or static faces flicking at 10 Hz. In particular, steady-state visual evoked potentials (SSVEPs) were quantified through spectral power analysis of EEG recordings. Besides, Granger causality (GC) analysis (GCA) was also performed to capture the causal cortical network dynamics during dynamic or static FEs of emotion. It was discovered that the dynamic (from neural to happy (N2H) or vice versa (H2N)) FEs elicited larger SSVEPs than the static ones. Additionally, GCA demonstrated that the H2N case, in which happy FEs were being gradually changed into neutral ones, exhibited larger GC measure during the late processing stage than that from the early stage. Consequently, enhanced SSVEPs and effective brain connectivity for dynamic FEs illustrated that participants might need consume more attentional resources to process the dynamic faces, particularly for the change from happy to neutral faces. The new neural index might facilitate us to better understand the cognitive processing of dynamic and static FEs.
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Affiliation(s)
- Meng-Yun Wang
- Faculty of Health Sciences, University of Macau, Taipa, Macau SAR, China; Centre for Cognitive and Brain Sciences, University of Macau, Taipa, Macau SAR, China
| | - Zhen Yuan
- Faculty of Health Sciences, University of Macau, Taipa, Macau SAR, China; Centre for Cognitive and Brain Sciences, University of Macau, Taipa, Macau SAR, China.
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23
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Framorando D, Moses E, Legrand L, Seeck M, Pegna AJ. Rapid processing of fearful faces relies on the right amygdala: evidence from individuals undergoing unilateral temporal lobectomy. Sci Rep 2021; 11:426. [PMID: 33432073 PMCID: PMC7801587 DOI: 10.1038/s41598-020-80054-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 12/10/2020] [Indexed: 11/22/2022] Open
Abstract
Facial expressions of emotions have been shown to modulate early ERP components, in particular the N170. The underlying anatomical structure producing these early effects are unclear. In this study, we examined the N170 enhancement for fearful expressions in healthy controls as well as epileptic patients after unilateral left or right amygdala resection. We observed a greater N170 for fearful faces in healthy participants as well as in individuals with left amygdala resections. By contrast, the effect was not observed in patients who had undergone surgery in which the right amygdala had been removed. This result demonstrates that the amygdala produces an early brain response to fearful faces. This early response relies specifically on the right amygdala and occurs at around 170 ms. It is likely that such increases are due to a heightened response of the extrastriate cortex that occurs through rapid amygdalofugal projections to the visual areas.
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Affiliation(s)
- David Framorando
- School of Psychology, The University of Queensland, Saint Lucia, Brisbane, QLD, 4068, Australia
| | - Eleanor Moses
- School of Psychology, The University of Queensland, Saint Lucia, Brisbane, QLD, 4068, Australia
| | - Lore Legrand
- Unit for Presurgical Evaluation of Epilepsy, Neurology Clinic, Geneva University Hospitals, 1205, Geneva, Switzerland
| | - Margitta Seeck
- Unit for Presurgical Evaluation of Epilepsy, Neurology Clinic, Geneva University Hospitals, 1205, Geneva, Switzerland
| | - Alan J Pegna
- School of Psychology, The University of Queensland, Saint Lucia, Brisbane, QLD, 4068, Australia.
- Unit for Presurgical Evaluation of Epilepsy, Neurology Clinic, Geneva University Hospitals, 1205, Geneva, Switzerland.
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24
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Danckert J, Striemer C, Rossetti Y. Blindsight. HANDBOOK OF CLINICAL NEUROLOGY 2021; 178:297-310. [PMID: 33832682 DOI: 10.1016/b978-0-12-821377-3.00016-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
For over a century, research has demonstrated that damage to primary visual cortex does not eliminate all capacity for visual processing in the brain. From Riddoch's (1917) early demonstration of intact motion processing for blind field stimuli, to the iconic work of Weiskrantz et al. (1974) showing reliable spatial localization, it is clear that secondary visual pathways that bypass V1 carry information to the visual brain that in turn influences behavior. In this chapter, we briefly outline the history and phenomena associated with blindsight, before discussing the nature of the secondary visual pathways that support residual visual processing in the absence of V1. We finish with some speculation as to the functional characteristics of these secondary pathways.
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Affiliation(s)
- James Danckert
- Department of Psychology, University of Waterloo, Waterloo, ON, Canada.
| | | | - Yves Rossetti
- Trajectoires, Centre de Recherche en Neurosciences de Lyon, Inserm, CNRS, Université Lyon 1, Bron, France; Plateforme "Mouvement et Handicap", Hôpital Henry-Gabrielle, Hospices Civils de Lyon, Saint-Genis-Laval, France
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25
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Gainotti G. Unconscious processing of emotions and the right hemisphere. HANDBOOK OF CLINICAL NEUROLOGY 2021; 183:27-46. [PMID: 34389122 DOI: 10.1016/b978-0-12-822290-4.00003-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Many influential authors maintain that, even if emotions are conscious experiences, the processing of information that produces emotions is usually unconscious. This chapter discusses the nonconscious aspects of emotional processing and the critical role played in them by the right hemisphere. This chapter first reviews the studies that have demonstrated the existence of unconscious or subconscious forms of emotional processing and then discusses the data supporting the hypothesis that the right hemisphere is dominant for the processing of emotions. After these topics are reviewed, the chapter will discuss investigations that have shown that the right and left amygdala have different roles in the processing of emotional stimuli, the former being involved in nonconscious and the latter in conscious forms of emotional learning. This chapter will also address the distinction proposed by Freud between "removed" and "nonremoved" forms of unconscious processing and will consider whether "nonremoved preverbal implicit memories" have a preferential link with the right hemisphere. The possibility that the right hemisphere may play a critical role not only in the formation of nonremoved subconscious memories but also in the development of denial phenomena, resulting from dynamic processes of unconscious repression, will also be discussed.
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Affiliation(s)
- Guido Gainotti
- Institute of Neurology, Catholic University, Rome, Italy; Department of Clinical and Behavioral Neurology, IRCCS Fondazione Santa Lucia, Rome, Italy.
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26
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Wang Y, Chen J, Ku Y. Subliminal affective priming effect: Dissociated processes for intense versus normal facial expressions. Brain Cogn 2020; 148:105674. [PMID: 33388551 DOI: 10.1016/j.bandc.2020.105674] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 11/28/2020] [Accepted: 12/20/2020] [Indexed: 11/15/2022]
Abstract
Positive vs. negative intense-facial expressions are difficult to explicitly distinguish; yet, whether they dissociate when subliminally presented remains unclear. Through three experiments using affective priming paradigms, we assessed how intense facial expressions, when presented briefly (17 ms) and masked, influenced following neutral ambiguous words (Experiment 1) or visible facial expressions (Experiments 2&3). We also compared these results with those of using normal facial expressions as primes in each experiment. All experiments indicated masked affective priming effects (biasing valence judgement of neutral words or facilitating reaction time to faces with the same valence as the prime) in normal facial expression, but not those intense ones. Experiment 3 using event related potentials (ERPs) further revealed that two ERP components N250 and LPP were consistent with behavioral changes in the normal condition (larger when valences of primes and targets were different), but inconsistent in the intense condition. Taken together, our results provided behavioral and neural evidence for distinctive processing between normal and intense facial expressions under masked condition.
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Affiliation(s)
- Yanmei Wang
- School of Psychology and Cognitive Science, East China Normal University, Shanghai 200062, China
| | - Jie Chen
- School of Psychology and Cognitive Science, East China Normal University, Shanghai 200062, China
| | - Yixuan Ku
- Guangdong Provincial Key Laboratory of Social Cognitive Neuroscience and Mental Health, Department of Psychology, Sun Yat-Sen University, Guangzhou 510006, China; Peng Cheng Laboratory, Shenzhen 518055, China.
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27
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Tao D, He Z, Lin Y, Liu C, Tao Q. Where does fear originate in the brain? A coordinate-based meta-analysis of explicit and implicit fear processing. Neuroimage 2020; 227:117686. [PMID: 33359340 DOI: 10.1016/j.neuroimage.2020.117686] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 12/10/2020] [Accepted: 12/11/2020] [Indexed: 11/16/2022] Open
Abstract
Processing of fear is of crucial importance for human survival and it can generally occur at explicit and implicit conditions. It is worth noting that explicit and implicit fear processing produces different behavioral and neurophysiological outcomes. The present study capitalizes on the Activation Likelihood Estimation (ALE) method of meta-analysis to identify: (a) the "core" network of fear processing in healthy individuals; (b) common and specific neural activations associated with explicit and implicit processing of fear. Following PRISMA guidelines, a total of 92 fMRI and PET studies were included in the meta-analysis. The overall analysis show that the core fear network comprises the amygdala, pulvinar, and fronto-occipital regions. Both implicit and explicit fear processing activated amygdala, declive, fusiform gyrus, and middle frontal gyrus, suggesting that these two types of fear processing share a common neural substrate. Explicit fear processing elicited more activations at the pulvinar and parahippocampal gyrus, suggesting visual attention/orientation and contextual association play important roles during explicit fear processing. In contrast, implicit fear processing elicited more activations at the cerebellum-amygdala-cortical pathway, indicating an 'alarm' system underlying implicit fear processing. These findings have shed light on the neural mechanism underlying fear processing at different levels of awareness.
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Affiliation(s)
- Di Tao
- International School, Jinan University, Guangzhou 510632, China
| | - Zonglin He
- International School, Jinan University, Guangzhou 510632, China
| | - Yuchen Lin
- International School, Jinan University, Guangzhou 510632, China
| | - Chang Liu
- International School, Jinan University, Guangzhou 510632, China
| | - Qian Tao
- Department of Public Health and Preventive Medicine, School of Basic Medicine, Jinan University, Guangzhou 510632, China; Division of Medical Psychology and Behavior Science, School of Basic Medicine, Jinan University, Guangzhou 510632, China; Center for Brain Science and Brain-Inspired Intelligence, Guangdong-Hong Kong-Macao Greater Bay Area, Guangzhou 510515, China.
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28
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Fear-related signals are prioritised in visual, somatosensory and spatial systems. Neuropsychologia 2020; 150:107698. [PMID: 33253690 DOI: 10.1016/j.neuropsychologia.2020.107698] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Accepted: 11/25/2020] [Indexed: 12/21/2022]
Abstract
The human brain has evolved a multifaceted fear system, allowing threat detection to enable rapid adaptive responses crucial for survival. Although many cortical and subcortical brain areas are believed to be involved in the survival circuits detecting and responding to threat, the amygdala has reportedly a crucial role in the fear system. Here, we review evidence demonstrating that fearful faces, a specific category of salient stimuli indicating the presence of threat in the surrounding, are preferentially processed in the fear system and in the connected sensory cortices, even when they are presented outside of awareness or are irrelevant to the task. In the visual domain, we discuss evidence showing in hemianopic patients that fearful faces, via a subcortical colliculo-pulvinar-amygdala pathway, have a privileged visual processing even in the absence of awareness and facilitate responses towards visual stimuli in the intact visual field. Moreover, evidence showing that somatosensory cortices prioritise fearful-related signals, to the extent that tactile processing is enhanced in the presence of fearful faces, will be also reported. Finally, we will review evidence revealing that fearful faces have a pivotal role in modulating responses in peripersonal space, in line with the defensive functional definition of PPS.
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29
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Kajal DS, Fioravanti C, Elshahabi A, Ruiz S, Sitaram R, Braun C. Involvement of top-down networks in the perception of facial emotions: A magnetoencephalographic investigation. Neuroimage 2020; 222:117075. [DOI: 10.1016/j.neuroimage.2020.117075] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 04/22/2020] [Accepted: 06/17/2020] [Indexed: 02/07/2023] Open
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Fateh AA, Cui Q, Duan X, Yang Y, Chen Y, Li D, He Z, Chen H. Disrupted dynamic functional connectivity in right amygdalar subregions differentiates bipolar disorder from major depressive disorder. Psychiatry Res Neuroimaging 2020; 304:111149. [PMID: 32738725 DOI: 10.1016/j.pscychresns.2020.111149] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 06/18/2020] [Accepted: 06/25/2020] [Indexed: 12/12/2022]
Abstract
Notwithstanding being the object of a growing field of clinical research, the investigation of the dynamic resting-state functional connectivity alterations in psychiatric illnesses is still in its early days. Current research on major depressive disorder (MDD) and bipolar disorder (BD) has evidenced abnormal resting-state functional connectivity (rsFC), especially in regions subserving emotional processing and regulation such as the amygdala. However, dynamic changes in functional connectivity within the amygdalar subregions in distinguishing BD and MDD has not yet been fully understood. In this paper, we aim at analyzing the patterns characterizing dynamic FC (dFC) in the right amygdala to investigate the differences between similarly depressed BD and MDD. A number of 40 BD patients, 61 MDD patients and 63 healthy controls (HCs) underwent functional magnetic resonance imaging (fMRI) at rest. Using the right-amygdala as seed region, we compared the dFC within three subdivisions, namely, laterobasal (LB), centromedial (CM) and superficial (SF) between all the groups. To do so, one-way ANOVA followed by post-hoc t-tests were employed. Compared to HCs, patients with BD had a decreased dFC between right LB and the left postcentral gyrus as well as an increased dFC between right CM and the right cerebellum.Compared to BD patients, patients with MDD showed a decreased dFC between right CM and the cerebellum and an increased dFC between right LB and the left postcentral gyrus. These findings present initial evidence that abnormal patterns of the right-amygdalar subregions shared by BD and MDD supports the differential pathophysiology of these disorders.
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Affiliation(s)
- Ahmed Ameen Fateh
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Qian Cui
- School of Public Affairs and Administration, University of Electronic Science and Technology of China, Chengdu, China.
| | - Xujun Duan
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Yang Yang
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Yuyan Chen
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Di Li
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Zongling He
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Huafu Chen
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China.
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Reflections on Eriksen's seminal essay on discrimination, performance and learning without awareness. Atten Percept Psychophys 2020; 83:546-557. [PMID: 32935288 DOI: 10.3758/s13414-020-02098-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Early in his career C.W. Eriksen published in Psychological Review what turned out to be a highly impactful critique on methods and findings on the topic of unconscious influences on discrimination and awareness. His incisive commentary on extant methodology employed at that time - especially the heavy dependence on subjective reports - clearly was heard by others moving forward, as evidenced by the subsequent, lively discussions within the literature concerning the very definition of the notion of unconscious processing. Of equal importance, Eriksen's paper provided an impetus for the development of more refined techniques for manipulating perceptual awareness and for measuring the consequences of those manipulations. My purpose in this essay is to ensure that Eriksen's seminal contributions concerning unconscious phenomena remain within the awareness of the many current investigators working on this popular topic.
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Ajina S, Pollard M, Bridge H. The Superior Colliculus and Amygdala Support Evaluation of Face Trait in Blindsight. Front Neurol 2020; 11:769. [PMID: 32765417 PMCID: PMC7379153 DOI: 10.3389/fneur.2020.00769] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 06/22/2020] [Indexed: 02/06/2023] Open
Abstract
Humans can respond rapidly to viewed expressions of fear, even in the absence of conscious awareness. This is demonstrated using visual masking paradigms in healthy individuals and in patients with cortical blindness due to damage to the primary visual cortex (V1) - so called affective blindsight. Humans have also been shown to implicitly process facial expressions representing important social dimensions. Two major axes, dominance and trustworthiness, are proposed to characterize the social dimensions of face evaluation. The processing of both types of implicit stimuli is believed to occur via similar subcortical pathways involving the amygdala. However, we do not know whether unconscious processing of more subtle expressions of facial traits can occur in blindsight, and if so, how. To test this, we studied 13 patients with unilateral V1 damage and visual field loss. We assessed their ability to detect and discriminate faces that had been manipulated along two orthogonal axes of trustworthiness and dominance to generate five trait levels inside the blind visual field: dominant, submissive, trustworthy, untrustworthy, and neutral. We compared neural activity and functional connectivity in patients classified as blindsight positive or negative for these stimuli. We found that dominant faces were most likely to be detected above chance, with individuals demonstrating unique interactions between performance and face trait. Only patients with blindsight (n = 8) showed significant preference in the superior colliculus and amygdala for face traits in the blind visual field, and a critical functional connection between the amygdala and superior colliculus in the damaged hemisphere. We also found a significant correlation between behavioral performance and fMRI activity in the amygdala and lateral geniculate nucleus across all participants. Our findings confirm that affective blindsight involving the superior colliculus and amygdala extends to the processing of socially salient but emotionally neutral facial expressions when V1 is damaged. This pathway is distinct from that which supports motion blindsight, as both types of blindsight can exist in the absence of the other with corresponding patterns of residual connectivity.
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Affiliation(s)
- Sara Ajina
- Department of Neurorehabilitation and Therapy Services, The National Hospital for Neurology and Neurosurgery, Queen Square, London, United Kingdom.,Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Miriam Pollard
- Institute of Neurology, University College London, London, United Kingdom
| | - Holly Bridge
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
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Danger is in the eyes of the beholder: The effect of visible and invisible affective faces on the judgment of social interactions. Cognition 2020; 203:104371. [PMID: 32569893 DOI: 10.1016/j.cognition.2020.104371] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 06/02/2020] [Accepted: 06/04/2020] [Indexed: 11/22/2022]
Abstract
Previous studies demonstrated that observation of facial expressions can modulate threat detection while looking at neutral or emotion-related scenes. Similarly, stimuli presented outside conscious awareness could influence social judgments of neutral novel stimuli. The two-fold aim of this study was: i) to evaluate whether observation of seen emotional faces could affect the judgment of social interactions without contextual cues (visible prime condition), and ii) whether this effect could also emerge when the emotional faces were made not visible by means of continuous flash suppression (invisible prime condition). We found that both seen and unseen faces are able to affect the judgment of ambiguous social interactions although this effect was particularly evident when affective faces were clearly visible. The present findings supported the idea that both conscious and unconscious processing of emotional faces have an important role in modulating perceivers' affective state and their judgment of social interactions.
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35
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Cartaud A, Ott L, Iachini T, Honoré J, Coello Y. The influence of facial expression at perceptual threshold on electrodermal activity and social comfort distance. Psychophysiology 2020; 57:e13600. [PMID: 32437046 DOI: 10.1111/psyp.13600] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Revised: 03/01/2020] [Accepted: 04/22/2020] [Indexed: 01/10/2023]
Abstract
Interpersonal distance, an essential component of social interaction, is modulated by the emotion conveyed by others and associated physiological response. However, in modern societies with overcrowded and hyperstimulating environments, we can only surreptitiously glimpse the faces of others in order to quickly make behavioral adjustments. How this impacts social interactions is not yet well understood. In the present study, we investigated this issue by testing whether facial expressions that are difficult to identify modify the physiological response (Electrodermal Activity, EDA) and subsequent judgment of interpersonal comfort distance. We recorded participants' EDA while they provided comfort judgments to interpersonal distances with a Point-Light Walker (PLW). The PLW, with an emotionally neutral gait, moved toward and crossed participants at various distances after the latter were exposed to a negative (anger), positive (happiness) or neutral facial expression presented at the perceptual threshold. Bayesian analyses of the data revealed an increase versus decrease of interpersonal comfort distance with the PLW depending on the negative versus positive emotional valence of the facial expression. They also showed an increase in EDA when the approaching PLW violated interpersonal comfort distance after participants were exposed to an angry facial expression. These effects correlated with the subjective assessment of the arousal of facial expressions. Thus, previous exposure to barely visible facial expressions can alter the representation of social comfort space and the physiological response associated with a violation of interpersonal comfort distances, depending on the valence and arousal of the emotional social stimuli.
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Affiliation(s)
- Alice Cartaud
- Laboratoire SCALab - Sciences Cognitives et Sciences Affectives, UMR CNRS 9193, Université Lille, Lille, France
| | - Laurent Ott
- Laboratoire SCALab - Sciences Cognitives et Sciences Affectives, UMR CNRS 9193, Université Lille, Lille, France
| | - Tina Iachini
- Laboratory of Cognitive Science and Immersive Virtual Reality, CS-IVR, Department of Psychology, University of Campania Luigi Vanvitelli, Caserte, Italy
| | - Jacques Honoré
- Laboratoire SCALab - Sciences Cognitives et Sciences Affectives, UMR CNRS 9193, Université Lille, Lille, France
| | - Yann Coello
- Laboratoire SCALab - Sciences Cognitives et Sciences Affectives, UMR CNRS 9193, Université Lille, Lille, France
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36
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Georgy L, Lewis JD, Bezgin G, Diano M, Celeghin A, Evans AC, Tamietto M, Ptito A. Changes in peri-calcarine cortical thickness in blindsight. Neuropsychologia 2020; 143:107463. [PMID: 32275967 PMCID: PMC7322521 DOI: 10.1016/j.neuropsychologia.2020.107463] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Revised: 03/09/2020] [Accepted: 04/02/2020] [Indexed: 11/24/2022]
Abstract
Blindsight is the ability of patients with primary visual cortex (V1) damage to process information in their clinically blind visual field in the absence of conscious awareness. In addition to those with localized V1 lesions, some patients exhibiting this phenomenon have had a cerebral hemisphere removed or disconnected from the rest of the brain for the treatment of drug-resistant epilepsy (hemispherectomy). Research into the underlying neural substrates of blindsight has long implicated the intact visual cortex in maintaining residual vision and supporting visuo-guided responses to stimuli presented ipsilaterally within the blind visual field while operating outside the geniculo-striate pathway. A recent study demonstrated functional reorganization in the dorsal visual areas of the intact hemisphere, thereby supporting its compensatory role in non-conscious vision. In this study, we used cortical thickness analysis to examine anatomical differences in the visual cortex of the intact hemisphere of three subjects with varying degrees of cortical damage and well documented blindsight: two with a right hemispherectomy (complete and partial), and one with a left V1 lesion. T1-weighted MRI data were obtained for the subjects while control data were chosen from publicly available NKI-dataset to match closely the acquisition parameters of our blindsight cases. Our results show significant increases in cortical thickness in the visual cortex of all blindsight subjects compared to healthy controls, irrespective of age-onset, etiology, and extent of the damage. Our findings add to accumulating evidence from behavioral, functional imaging, and tractography studies of cerebral compensation and reorganization. Examined anatomical changes in the intact visual cortex of rare blindsight patients. First comparison of hemispherectomy and lesion patients to a large control sample. Blindsight subjects show significant increases in peri-calcarine cortical thickness. Similar changes observed despite differences in etiology and age at time of lesion. Increases are possible morphological signs of compensation underlying blindsight.
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Affiliation(s)
- Loraine Georgy
- Montreal Neurological Institute, McGill University, Montreal, Canada.
| | - John D Lewis
- Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Gleb Bezgin
- Montreal Neurological Institute, McGill University, Montreal, Canada; McGill Centre for Studies in Aging, Douglas Institute, McGill University, Montreal, Canada
| | - Matteo Diano
- Department of Psychology, University of Torino, Torino, Italy
| | | | - Alan C Evans
- Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Marco Tamietto
- Department of Psychology, University of Torino, Torino, Italy; Center of Research on Psychology in Somatic Diseases - CoRPS - Tilburg University, the Netherlands
| | - Alain Ptito
- Montreal Neurological Institute, McGill University, Montreal, Canada; Department of Psychology, McGill University Health Centre, Montreal, Canada
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37
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Fox DM, Goodale MA, Bourne JA. The Age-Dependent Neural Substrates of Blindsight. Trends Neurosci 2020; 43:242-252. [PMID: 32209455 DOI: 10.1016/j.tins.2020.01.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 01/22/2020] [Accepted: 01/23/2020] [Indexed: 12/15/2022]
Abstract
Some patients who are considered cortically blind due to the loss of their primary visual cortex (V1) show a remarkable ability to act upon or discriminate between visual stimuli presented to their blind field, without any awareness of those stimuli. This phenomenon is often referred to as blindsight. Despite the range of spared visual abilities, the identification of the pathways mediating blindsight remains an active and contentious topic in the field. In this review, we discuss recent findings of the candidate pathways and their relative contributions to different forms of blindsight across the lifespan to illustrate the varied nature of unconscious visual processing.
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Affiliation(s)
- Dylan M Fox
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia
| | - Melvyn A Goodale
- The Brain and Mind Institute, The University of Western Ontario, Western Interdisciplinary Research Building, London, Ontario, Canada
| | - James A Bourne
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia.
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38
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Le QV, Le QV, Nishimaru H, Matsumoto J, Takamura Y, Hori E, Maior RS, Tomaz C, Ono T, Nishijo H. A Prototypical Template for Rapid Face Detection Is Embedded in the Monkey Superior Colliculus. Front Syst Neurosci 2020; 14:5. [PMID: 32158382 PMCID: PMC7025518 DOI: 10.3389/fnsys.2020.00005] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Accepted: 01/20/2020] [Indexed: 01/30/2023] Open
Abstract
Human babies respond preferentially to faces or face-like images. It has been proposed that an innate and rapid face detection system is present at birth before the cortical visual pathway is developed in many species, including primates. However, in primates, the visual area responsible for this process is yet to be unraveled. We hypothesized that the superior colliculus (SC) that receives direct and indirect retinal visual inputs may serve as an innate rapid face-detection system in primates. To test this hypothesis, we examined the responsiveness of monkey SC neurons to first-order information of faces required for face detection (basic spatial layout of facial features including eyes, nose, and mouth), by analyzing neuronal responses to line drawing images of: (1) face-like patterns with contours and properly placed facial features; (2) non-face patterns including face contours only; and (3) nonface random patterns with contours and randomly placed face features. Here, we show that SC neurons respond stronger and faster to upright and inverted face-like patterns compared to the responses to nonface patterns, regardless of contrast polarity and contour shapes. Furthermore, SC neurons with central receptive fields (RFs) were more selective to face-like patterns. In addition, the population activity of SC neurons with central RFs can discriminate face-like patterns from nonface patterns as early as 50 ms after the stimulus onset. Our results provide strong neurophysiological evidence for the involvement of the primate SC in face detection and suggest the existence of a broadly tuned template for face detection in the subcortical visual pathway.
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Affiliation(s)
- Quang Van Le
- System Emotional Science, Faculty of Medicine, University of Toyama, Toyama, Japan
| | - Quan Van Le
- System Emotional Science, Faculty of Medicine, University of Toyama, Toyama, Japan
| | - Hiroshi Nishimaru
- System Emotional Science, Faculty of Medicine, University of Toyama, Toyama, Japan
| | - Jumpei Matsumoto
- System Emotional Science, Faculty of Medicine, University of Toyama, Toyama, Japan
| | - Yusaku Takamura
- System Emotional Science, Faculty of Medicine, University of Toyama, Toyama, Japan
| | - Etsuro Hori
- System Emotional Science, Faculty of Medicine, University of Toyama, Toyama, Japan
| | - Rafael S Maior
- Primate Center and Laboratory of Neurosciences and Behavior, Department of Physiological Sciences, Institute of Biology, University of Brasília, Brasilia, Brazil
| | - Carlos Tomaz
- Laboratory of Neuroscience and Behavior, CEUMA University, São Luis, Brazil
| | - Taketoshi Ono
- System Emotional Science, Faculty of Medicine, University of Toyama, Toyama, Japan
| | - Hisao Nishijo
- System Emotional Science, Faculty of Medicine, University of Toyama, Toyama, Japan
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39
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Paul ES, Sher S, Tamietto M, Winkielman P, Mendl MT. Towards a comparative science of emotion: Affect and consciousness in humans and animals. Neurosci Biobehav Rev 2020; 108:749-770. [PMID: 31778680 PMCID: PMC6966324 DOI: 10.1016/j.neubiorev.2019.11.014] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 10/08/2019] [Accepted: 11/18/2019] [Indexed: 02/06/2023]
Abstract
The componential view of human emotion recognises that affective states comprise conscious, behavioural, physiological, neural and cognitive elements. Although many animals display bodily and behavioural changes consistent with the occurrence of affective states similar to those seen in humans, the question of whether and in which species these are accompanied by conscious experiences remains controversial. Finding scientifically valid methods for investigating markers for the subjective component of affect in both humans and animals is central to developing a comparative understanding of the processes and mechanisms of affect and its evolution and distribution across taxonomic groups, to our understanding of animal welfare, and to the development of animal models of affective disorders. Here, contemporary evidence indicating potential markers of conscious processing in animals is reviewed, with a view to extending this search to include markers of conscious affective processing. We do this by combining animal-focused approaches with investigations of the components of conscious and non-conscious emotional processing in humans, and neuropsychological research into the structure and functions of conscious emotions.
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Affiliation(s)
- Elizabeth S Paul
- Bristol Veterinary School, University of Bristol, Langford House, Langford, Bristol, BS40 5DU, UK.
| | - Shlomi Sher
- Department of Psychology, Pomona College, Claremont, CA, USA
| | - Marco Tamietto
- Department of Medical and Clinical Psychology, Tilburg University, Tilburg, the Netherlands; Department of Psychology, University of Torino, Torino, Italy
| | - Piotr Winkielman
- Department of Psychology, University of California, San Diego, La Jolla, CA, 92093, USA; Faculty of Psychology, SWPS University of Social Sciences and Humanities, 03-815, Warsaw, Poland
| | - Michael T Mendl
- Bristol Veterinary School, University of Bristol, Langford House, Langford, Bristol, BS40 5DU, UK
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40
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Neural correlates of emotion-attention interactions: From perception, learning, and memory to social cognition, individual differences, and training interventions. Neurosci Biobehav Rev 2020; 108:559-601. [DOI: 10.1016/j.neubiorev.2019.08.017] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Revised: 07/02/2019] [Accepted: 08/21/2019] [Indexed: 12/12/2022]
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41
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Dinh HT, Nishimaru H, Matsumoto J, Takamura Y, Le QV, Hori E, Maior RS, Tomaz C, Tran AH, Ono T, Nishijo H. Superior Neuronal Detection of Snakes and Conspecific Faces in the Macaque Medial Prefrontal Cortex. Cereb Cortex 2019; 28:2131-2145. [PMID: 28498964 DOI: 10.1093/cercor/bhx118] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 04/25/2017] [Indexed: 11/14/2022] Open
Abstract
Snakes and conspecific faces are quickly and efficiently detected in primates. Because the medial prefrontal cortex (mPFC) has been implicated in attentional allocation to biologically relevant stimuli, we hypothesized that it might also be highly responsive to snakes and conspecific faces. In this study, neuronal responses in the monkey mPFC were recorded, while monkeys discriminated 8 categories of visual stimuli. Here, we show that the monkey mPFC neuronal responses to snakes and conspecific faces were unique. First, the ratios of the neurons that responded strongly to snakes and monkey faces were greater than those of the neurons that responded strongly to the other stimuli. Second, mPFC neurons responded stronger and faster to snakes and monkey faces than the other categories of stimuli. Third, neuronal responses to snakes were unaffected by low-pass filtering of the images. Finally, activity patterns of responsive mPFC neurons discriminated snakes from the other stimuli in the second 50 ms period and monkey faces in the third period after stimulus onset. These response features indicate that the mPFC processes fast and coarse visual information of snakes and monkey faces, and support the hypothesis that snakes and social environments have shaped the primate visual system over evolutionary time.
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Affiliation(s)
- Ha Trong Dinh
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani 2630, Toyama 930-0194, Japan
| | - Hiroshi Nishimaru
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani 2630, Toyama 930-0194, Japan
| | - Jumpei Matsumoto
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani 2630, Toyama 930-0194, Japan
| | - Yusaku Takamura
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani 2630, Toyama 930-0194, Japan
| | - Quan Van Le
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani 2630, Toyama 930-0194, Japan.,Department of Physiology, Vietnam Military Medical University, Ha noi 100000, Vietnam
| | - Etsuro Hori
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani 2630, Toyama 930-0194, Japan
| | - Rafael S Maior
- Primate Center and Laboratory of Neurosciences and Behavior, Department of Physiological Sciences, Institute of Biology, University of Brasília, CEP 70910-900 Brasilia, DF, Brazil.,Department of Clinical Neuroscience, Karolinska Institute, Psychiatry Section, Karolinska Hospital, S-17176 Stockholm, Sweden
| | - Carlos Tomaz
- Primate Center and Laboratory of Neurosciences and Behavior, Department of Physiological Sciences, Institute of Biology, University of Brasília, CEP 70910-900 Brasilia, DF, Brazil.,Neuroscience Research Coordenation, University CEUMA, Campus Renascença, CEP 65.075-120 São Luis, MA, Brazil
| | - Anh Hai Tran
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani 2630, Toyama 930-0194, Japan.,Department of Physiology, Vietnam Military Medical University, Ha noi 100000, Vietnam
| | - Taketoshi Ono
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani 2630, Toyama 930-0194, Japan
| | - Hisao Nishijo
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani 2630, Toyama 930-0194, Japan
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42
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Lucas N, Bourgeois A, Carrera E, Landis T, Vuilleumier P. Impaired visual search with paradoxically increased facilitation by emotional features after unilateral pulvinar damage. Cortex 2019; 120:223-239. [PMID: 31336355 DOI: 10.1016/j.cortex.2019.06.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 05/13/2019] [Accepted: 06/07/2019] [Indexed: 12/23/2022]
Abstract
Posterior thalamic pulvinar nuclei have been implicated in different aspects of spatial attention, but their exact role in humans remain unclear. Most neuropsychological studies of attention deficits after pulvinar lesion have concerned single patients or small samples. Here we examined a group of 13 patients with focal damage to posterior thalamus on a visual search task with faces, allowing us to test several hypotheses concerning pulvinar function in controlling attention to visually salient or emotionally significant stimuli. Our results identified two subgroups of thalamic patients with distinct patterns of attentional responsiveness to emotional and colour features in face targets. One group with lesions located in anterior and ventral portions of thalamus showed intact performance, with a normal facilitation of visual search for faces with emotional (fearful or happy) expressions on both side of space, similar to healthy controls. By contrast, a second group showed a slower and poorer detection of face targets, most severe for neutral faces, but with a paradoxically enhanced facilitation by both colour and emotional features. This second group had lesions centred on the pulvinar, involving mainly the dorso-medial sectors in patients showing enhanced effects of colour features, but extending to more dorso-lateral sectors in those with enhanced effects of emotional features. These findings reveal that pulvinar nuclei are not critical for orienting attention to emotionally or visually salient features, but instead provide new evidence in support of previous hypotheses suggesting an important role in controlling attention in visual scenes with distracting information.
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Affiliation(s)
- Nadia Lucas
- Neuroscience Department, Laboratory for Behavioral Neurology and Imaging of Cognition, University of Geneva, Geneva, Switzerland
| | - Alexia Bourgeois
- Neuroscience Department, Laboratory for Behavioral Neurology and Imaging of Cognition, University of Geneva, Geneva, Switzerland; Neurology Department, University Hospital of Geneva, Geneva, Switzerland; Laboratory of Cognitive Neurorehabilitation, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
| | - Emmanuel Carrera
- Neurology Department, University Hospital of Geneva, Geneva, Switzerland
| | - Theodor Landis
- Neurology Department, University Hospital of Geneva, Geneva, Switzerland
| | - Patrik Vuilleumier
- Neuroscience Department, Laboratory for Behavioral Neurology and Imaging of Cognition, University of Geneva, Geneva, Switzerland; Neurology Department, University Hospital of Geneva, Geneva, Switzerland
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43
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Striemer CL, Whitwell RL, Goodale MA. Affective blindsight in the absence of input from face processing regions in occipital-temporal cortex. Neuropsychologia 2019; 128:50-57. [DOI: 10.1016/j.neuropsychologia.2017.11.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 11/01/2017] [Accepted: 11/10/2017] [Indexed: 10/18/2022]
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44
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Rolls ET. The orbitofrontal cortex and emotion in health and disease, including depression. Neuropsychologia 2019; 128:14-43. [DOI: 10.1016/j.neuropsychologia.2017.09.021] [Citation(s) in RCA: 106] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 09/04/2017] [Accepted: 09/20/2017] [Indexed: 12/16/2022]
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45
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Pathways for smiling, disgust and fear recognition in blindsight patients. Neuropsychologia 2019; 128:6-13. [DOI: 10.1016/j.neuropsychologia.2017.08.028] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 08/03/2017] [Accepted: 08/28/2017] [Indexed: 01/08/2023]
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Bertini C, Cecere R, Làdavas E. Unseen fearful faces facilitate visual discrimination in the intact field. Neuropsychologia 2019; 128:58-64. [DOI: 10.1016/j.neuropsychologia.2017.07.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 07/24/2017] [Accepted: 07/25/2017] [Indexed: 12/19/2022]
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Unconscious fearful body perception enhances discrimination of conscious anger expressions under continuous flash suppression. Neuropsychologia 2019; 128:325-331. [DOI: 10.1016/j.neuropsychologia.2018.04.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 04/19/2018] [Accepted: 04/20/2018] [Indexed: 02/09/2023]
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Maratos FA, Pessoa L. What drives prioritized visual processing? A motivational relevance account. PROGRESS IN BRAIN RESEARCH 2019; 247:111-148. [PMID: 31196431 DOI: 10.1016/bs.pbr.2019.03.028] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Emotion is fundamental to our being, and an essential aspect guiding behavior when rapid responding is required. This includes whether we approach or avoid a stimulus, and the accompanying physiological responses. A common tenet is that threat-related content drives stimulus processing and biases visual attention, so that rapid responding can be initiated. In this paper, it will be argued instead that prioritization of threatening stimuli should be encompassed within a motivational relevance framework. To more fully understand what is, or is not, prioritized for visual processing one must, however, additionally consider: (i) stimulus ambiguity and perceptual saliency; (ii) task demands, including both perceptual load and cognitive load; and (iii) endogenous/affective states of the individual. Combined with motivational relevance, this then leads to a multifactorial approach to understanding the drivers of prioritized visual processing. This accords with current recognition that the brain basis allowing for visual prioritization is also multifactorial, including transient, dynamic and overlapping networks. Taken together, the paper provides a reconceptualization of how "emotional" information prioritizes visual processing.
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Affiliation(s)
- Frances Anne Maratos
- Department of Psychology and Human Sciences Research Centre, University of Derby, Derby, United Kingdom.
| | - Luiz Pessoa
- Department of Psychology and Maryland Neuroimaging Center, University of Maryland, College Park, MD, United States
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Lojowska M, Mulckhuyse M, Hermans EJ, Roelofs K. Unconscious processing of coarse visual information during anticipatory threat. Conscious Cogn 2019; 70:50-56. [PMID: 30826718 DOI: 10.1016/j.concog.2019.01.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 12/12/2018] [Accepted: 01/30/2019] [Indexed: 12/27/2022]
Abstract
Rapid detection of threats has been proposed to rely on automatic processing of their coarse visual features. However, it remains unclear whether such a mechanism is restricted to detection of threat cues, or whether it reflects a broader sensitivity to even neutral coarse visual information features during states of threat. We used a backward masking task in which participants discriminated the orientation of subliminally presented low (3 cpd) and high (6 cpd) spatial frequency gratings, under threat (of shock) and safe conditions. Visual awareness of the gratings was assessed objectively using an additional localization task. When participants were unaware of the gratings, above chance and improved discrimination of low-spatial frequency gratings was observed under threat compared to safe trials. These findings demonstrate unconscious processing of neutral coarse visual information during threat state, supporting the view that automatic threat detection may rely on a general facilitation of coarse features irrespective of threat content.
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Affiliation(s)
- Maria Lojowska
- Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands; Behavioural Science Institute, Radboud University, Nijmegen, the Netherlands.
| | - Manon Mulckhuyse
- Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands; Behavioural Science Institute, Radboud University, Nijmegen, the Netherlands
| | - Erno J Hermans
- Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands; Radboud University Medical Center, Nijmegen, the Netherlands
| | - Karin Roelofs
- Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands; Behavioural Science Institute, Radboud University, Nijmegen, the Netherlands
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Neuronal mechanisms of motion detection underlying blindsight assessed by functional magnetic resonance imaging (fMRI). Neuropsychologia 2019; 128:187-197. [PMID: 30825453 DOI: 10.1016/j.neuropsychologia.2019.02.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 02/15/2019] [Accepted: 02/19/2019] [Indexed: 12/27/2022]
Abstract
Brain imaging offers a valuable tool to observe functional brain plasticity by showing how sensory inputs reshape cortical activations after a visual impairment. Following a unilateral post-chiasmatic lesion affecting the visual cortex, patients may suffer a contralateral visual loss referred to homonymous hemianopia. Nevertheless, these patients preserve the ability to unconsciously detect, localize and discriminate visual stimuli presented in their impaired visual field. To investigate this paradox, known as blindsight, we conducted a study using functional magnetic resonance imaging (fMRI) to evaluate the structural and functional impact of such lesion in a 33-year old patient (ML), who suffers a complete right hemianopia without macular sparing and showing strong evidences of blindsight. We thus performed whole brain and sliced thalamic fMRI scan sequences during an event-related motion detection task. We provided evidence of the neuronal fingerprint of blindsight by acquiring and associating neural correlates, specific structures and functional networks of the midbrain during blindsight performances which may help to better understand this condition. Accurate performance demonstrated the presence of residual vision and the ability to unconsciously perceive motion presented in the blind hemifield, although her reaction time was significantly higher in her blind-field. When the normal hemifield was stimulated, we observed significant contralateral activations in primary and secondary visual areas as well as motion specific areas, such as the supramarginal gyrus and middle temporal area. We also demonstrated sub-thalamic activations within the superior colliculi (SC) and the pulvinar. These results suggest a role of secondary subcortical structures in normal spontaneous motion detection. In a similar way, when the lesioned hemifield was stimulated, we observed contralateral activity in extrastriate areas with no activation of the primary lesioned visual cortex. Moreover, we observed activations within the SC when the blind hemifield was stimulated. However, we observed unexpected ipsilateral activations within the same motion specific areas, as well as bilateral frontal activations. These results highlight the importance of abnormal secondary pathways bypassing the primary visual area (V1) in residual vision. This reorganization in the structure and function of the visual pathways correlates with behavioral changes, thus offering a plausible explanation for the blindsight phenomenon. Our results may potentially impact the development of rehabilitation strategies to target subcortical pathways.
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