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Marco Tamietto

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Papers by Marco Tamietto

Psychophysiological mechanisms guiding recognition of basic and complex emotions without visual cortex

Faces, Bodies, Social Vision as Agent Vision, and Social Consciousness

Oxford University Press eBooks, Nov 16, 2010

This chapter discusses recent findings from research on face and body perception giving special a... more This chapter discusses recent findings from research on face and body perception giving special attention to the implications of the findings for social vision. The first section is devoted to similarities between the processes underlying face and body perception. The second section discusses how the perception of faces and bodies is integrated. The third section tackles issues on conscious and nonconscious perception of socially meaningful signals and their neuroanatomical underpinnings. Finally, the relation between social vision and awareness is explored, and notion of social consciousness is developed. Throughout the chapter, the notions of agent vision and social vision are used in the sense made familiar by the expression "night vision" to refer to various devices that expand the normal visual abilities and allows the observer to see in the dark, outside the spotlight of consciousness.

Subcortical Connections to Human Amygdala and Changes following Destruction of the Visual Cortex

Current Biology, Aug 1, 2012

A deep neural network model of the primate superior colliculus for emotion recognition

Philosophical Transactions of the Royal Society B: Biological Sciences

Although sensory processing is pivotal to nearly every theory of emotion, the evaluation of the v... more 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 t...

Report Subcortical Connections to Human Amygdala and Changes following Destruction of the Visual Cortex

Report uman Amygdala and Changes following Destruction of the Visual Cortex

Marco Tamietto,1,5,* Pim Pullens,2,5 Beatrice de Gelder,1,2 Lawrence Weiskrantz,3 and Rainer Goeb... more Marco Tamietto,1,5,* Pim Pullens,2,5 Beatrice de Gelder,1,2 Lawrence Weiskrantz,3 and Rainer Goebel2,4 1Cognitive and Affective Neuroscience Laboratory, Tilburg University, 5000 LE Tilburg, The Netherlands 2Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, 6200 MD Maastricht, The Netherlands 3Department of Experimental Psychology, University of Oxford, Oxford OX1 3UD, UK 4Netherlands Institute for Neuroscience (NIN), an Institute of the Royal Netherlands Academy of Arts and Sciences (KNAW), 1105 BA Amsterdam, The Netherlands

Human Amygdala in Sensory and Attentional Unawareness: Neural Pathways and Behavioural Outcomes

One of the neural structures more often implicated in the processing of emotional signals in the ... more One of the neural structures more often implicated in the processing of emotional signals in the absence of visual awareness is the amygdala. In this chapter, we review current evidence from human neuroscience in healthy and brain-damaged patients on the role of amygdala during non-conscious (visual) perception of emotional stimuli. Nevertheless, there is as of yet no consensus on the limits and conditions that affect the extent of amygdala's response without focused attention or awareness. We propose to distinguish between attentional unawareness, a condition wherein the stimulus is potentially accessible to enter visual awareness but fails to do so because attention is diverted, and sensory unawareness, in which the stimulus fails to enter awareness because its normal processing in the visual cortex is suppressed. Within this conceptual framework, some of the apparently contradictory findings seem to gain new coherence and converge on the role of the amygdala in supporting different types of non-conscious emotion processing. Amygdala responses in the absence of awareness are linked to different functional mechanisms and are driven by more complex neural networks than commonly assumed. Acknowledging this complexity can be helpful to foster new studies on amygdala functions without awareness and their impact on human behaviour.

Functional neuroanatomy of racial categorization from visual perception: A meta-analytic study

NeuroImage, 2020

We effortlessly sort people into different racial groups from their visual appearance and implici... more We effortlessly sort people into different racial groups from their visual appearance and implicitly generate racial bias affecting cognition and behavior. As these mental activities provide the proximate mechanisms for social behaviours, it becomes essential to understand the neural activity underlying differences between own-race and other-race visual categorization. Yet intrinsic limitations of individual neuroimaging studies, owing to reduced sample size, inclusion of multiple races, and interactions between races in the participants and in the displayed visual stimuli, dampens generalizability of results. In the present meta-analytic study, we applied multimodal techniques to partly overcome these hurdles, and we investigated the entire functional neuroimaging literature on race categorization, therefore including more than 2000 Black, White and Asian participants. Our data-driven approach shows that own-and other-race visual categorization involves partly segregated neural networks, with distinct connectivity and functional profiles, and defined hierarchical organization. Categorization of ownrace mainly engages areas related to cognitive components of empathy and mentalizing, such as the medial prefrontal cortex and the inferior frontal gyrus. These areas are functionally co-activated with cortical structures involved in auto-biographical memories and social knowledge. Conversely, other-race categorization recruits areas implicated in, and functionally connected with, visuo-attentive processing, like the fusiform gyrus and the inferior parietal lobule, and areas engaged in affective functions, like the amygdala. These results contribute to a better definition of the neural networks involved in the visual parcelling of social categories based on race, and help to situate these processes within a common neural space.

Toward an integrative science of social vision in intergroup bias

Neuroscience & Biobehavioral Reviews, 2019

 Social categories and intergroup bias can be derived from face perception.  Social categorizat... more  Social categories and intergroup bias can be derived from face perception.  Social categorization is sensitive elemental visual features in the face.  Prior knowledge and expectations modulate facial representations.  This evidence challenges accounts based on hierarchical brain organization.  A new model building on recursive dynamic interactions is proposed.

Emotion Recognition in Low-Spatial Frequencies Is Partly Preserved following Traumatic Brain Injury

BioMed Research International, 2019

After a Traumatic Brain Injury (TBI), emotion recognition is typically impaired. This is commonly... more After a Traumatic Brain Injury (TBI), emotion recognition is typically impaired. This is commonly attributed to widespread multifocal damage in cortical areas involved in emotion processing as well as to Diffuse Axonal Injury (DAI). However, current models suggest that emotional recognition is subserved by a distributed network cantered on the amygdala, which involves both cortical and subcortical structures. While the cortical system is preferentially tuned to process high spatial frequencies, the subcortical networks are more sensitive to low-spatial frequencies. The aim of this study was to evaluate whether emotion perception from low-spatial frequencies underpinning the subcortical system is relatively preserved in TBI patients. We tested a group of 14 subjects with severe TBI and 20 matched healthy controls. Each participant was asked to recognize the emotion expressed by each stimulus that consisted of happy and fearful faces, filtered for their low and high spatial frequencie...

Classical paintings may trigger pain and pleasure in the gendered brain

Cortex; a journal devoted to the study of the nervous system and behavior, Jan 28, 2018

The human body is the most common object of pictorial representation in western art and its repre... more The human body is the most common object of pictorial representation in western art and its representations trigger a vast range of experiences from pain to pleasure. The goal of this study was to investigate brain activity triggered by paintings of male and female body images exemplifying conditions associated with pleasure or pain. Our findings show participant-general as well as gender specific brain activity for either the pain or the pleasure conditions. Although our participants were fully aware that they were viewing artworks, the inferior parietal lobule - known for its role in the perception of emotional body images - and the somatosensory cortex related to touch were selectively active for female body paintings in all participants in the pleasure conditions. As regards gender we observed that the sight of female bodies activated the subgenual anterior cingulate cortex in males, an area known to subserve autonomic arousal. In contrast, in females the sight of the male body ...

Functional Neuroanatomy of Blindsight Revealed by Activation Likelihood Estimation Meta-analysis

Neuropsychologia, Jan 9, 2018

Blindsight, the residual abilities of patients with cortical blindness to respond proficiently to... more Blindsight, the residual abilities of patients with cortical blindness to respond proficiently to stimuli they do not consciously acknowledge, offers a unique opportunity to study the functional and anatomical mechanisms sustaining visual awareness. Over decades, the phenomenon has been documented in a wide number of different patients, across independent laboratories, and for a variety of tasks and stimulus properties. Nevertheless, the functional neuroanatomy of blindsight remains elusive and alternative proposals have been put forth. To tackle this issue from a novel perspective, we performed a quantitative Activation Likelihood Estimation (ALE) meta-analysis on the neuroimaging literature available on blindsight. Significant activity was reported in subcortical structures, such as the superior colliculus, pulvinar and amygdala, as well as in cortical extrastriate areas along the dorsal and ventral visual stream. This data-driven functional network collectively defines the extant...

Basic Emotions in Human Neuroscience: Neuroimaging and Beyond

Frontiers in Psychology, 2017

Amygdala Response to Emotional Stimuli without Awareness: Facts and Interpretations

Frontiers in Psychology, 2017

Over the past two decades, evidence has accumulated that the human amygdala exerts some of its fu... more Over the past two decades, evidence has accumulated that the human amygdala exerts some of its functions also when the observer is not aware of the content, or even presence, of the triggering emotional stimulus. Nevertheless, there is as of yet no consensus on the limits and conditions that affect the extent of amygdala's response without focused attention or awareness. Here we review past and recent studies on this subject, examining neuroimaging literature on healthy participants as well as braindamaged patients, and we comment on their strengths and limits. We propose a theoretical distinction between processes involved in attentional unawareness, wherein the stimulus is potentially accessible to enter visual awareness but fails to do so because attention is diverted, and in sensory unawareness, wherein the stimulus fails to enter awareness because its normal processing in the visual cortex is suppressed. We argue this distinction, along with data sampling amygdala responses with high temporal resolution, helps to appreciate the multiplicity of functional and anatomical mechanisms centered on the amygdala and supporting its role in non-conscious emotion processing. Separate, but interacting, networks relay visual information to the amygdala exploiting different computational properties of subcortical and cortical routes, thereby supporting amygdala functions at different stages of emotion processing. This view reconciles some apparent contradictions in the literature, as well as seemingly contrasting proposals, such as the dual stage and the dual route model. We conclude that evidence in favor of the amygdala response without awareness is solid, albeit this response originates from different functional mechanisms and is driven by more complex neural networks than commonly assumed. Acknowledging the complexity of such mechanisms can foster new insights on the varieties of amygdala functions without awareness and their impact on human behavior.

Dynamic Changes in Amygdala Psychophysiological Connectivity Reveal Distinct Neural Networks for Facial Expressions of Basic Emotions

Scientific reports, Mar 27, 2017

The quest to characterize the neural signature distinctive of different basic emotions has recent... more The quest to characterize the neural signature distinctive of different basic emotions has recently come under renewed scrutiny. Here we investigated whether facial expressions of different basic emotions modulate the functional connectivity of the amygdala with the rest of the brain. To this end, we presented seventeen healthy participants (8 females) with facial expressions of anger, disgust, fear, happiness, sadness and emotional neutrality and analyzed amygdala's psychophysiological interaction (PPI). In fact, PPI can reveal how inter-regional amygdala communications change dynamically depending on perception of various emotional expressions to recruit different brain networks, compared to the functional interactions it entertains during perception of neutral expressions. We found that for each emotion the amygdala recruited a distinctive and spatially distributed set of structures to interact with. These changes in amygdala connectional patters characterize the dynamic sign...

Looming sensitive cortical regions without V1 input: evidence from a patient with bilateral cortical blindness

Frontiers in Integrative Neuroscience, 2015

Fast and automatic behavioral responses are required to avoid collision with an approaching stimu... more Fast and automatic behavioral responses are required to avoid collision with an approaching stimulus. Accordingly, looming stimuli have been found to be highly salient and efficient attractors of attention due to the implication of potential collision and potential threat. Here, we address the question of whether looming motion is processed in the absence of any functional primary visual cortex and consequently without awareness. For this, we investigated a patient (TN) suffering from complete, bilateral damage to his primary visual cortex. Using an fMRI paradigm, we measured TN's brain activation during the presentation of looming, receding, rotating, and static point lights, of which he was unaware. When contrasted with other conditions, looming was found to produce bilateral activation of the middle temporal areas, as well as the superior temporal sulcus and inferior parietal lobe (IPL). The latter are generally thought to be involved in multisensory processing of motion in extrapersonal space, as well as attentional capture and saliency. No activity was found close to the lesioned V1 area. This demonstrates that looming motion is processed in the absence of awareness through direct subcortical projections to areas involved in multisensory processing of motion and saliency that bypass V1.

Beyond the face: exploring rapid influences of context on face processing

Progress in brain research, 2006

Humans optimize behavior by deriving context-based expectations. Contextual data that are importa... more Humans optimize behavior by deriving context-based expectations. Contextual data that are important for survival are extracted rapidly, using coarse information, adaptive decision strategies, and dedicated neural infrastructure. In the field of object perception, the influence of a surrounding context has been a major research theme, and it has generated a large literature. That visual context, as typically provided by natural scenes, facilitates object recognition as has been convincingly demonstrated (Bar, M. (2004) Nat. Rev. Neurosci., 5: 617-629). Just like objects, faces are generally encountered as part of a natural scene. Thus far, the facial expression literature has neglected such context and treats facial expressions as if they stand on their own. This constitutes a major gap in our knowledge. Facial expressions tend to appear in a context of head and body orientations, body movements, posture changes, and other object-related actions with a similar or at least a closely r...

Faces, Bodies, Social Vision as Agent Vision, and Social Consciousness

The Science of Social Vision, 2010

This chapter discusses recent findings from research on face and body perception giving special a... more