Thierry Chaminade

• PhD
• Researcher at French National Centre for Scientific Research

Artificial agents are expected to increasingly interact with humans and to demonstrate multimodal adaptive emotional responses. Such social integration requires both perception and production mechanisms, thus enabling a more realistic approach to emotional alignment than existing systems. Indeed, existing emotion recognition methods rely on behavio...

Discussion is a fundamental social activity requiring coordination of speech between interlocutors. Speech production is a complex human behaviour that involves several anatomo-physiological processes, including inspiration and expiration. The aim of the present study is to investigate the neurophysiological underpinnings of speech-related respirat...

Addictions often develop in a social context, although the influence of social factors did not receive much attention in the neuroscience of addiction. Recent animal studies suggest that peer presence can reduce cocaine intake, an influence potentially mediated, among others, by the subthalamic nucleus (STN). However, there is to date no neurobiolo...

We present an analytical framework aimed at predicting the local brain activity in uncontrolled experimental conditions based on multimodal recordings of participants’ behavior, and its application to a corpus of participants having conversations with another human or a conversational humanoid robot. The framework consists in extracting high-level...

Background Addictions often develop in a social context, although the influence of social factors did not receive much attention in the neuroscience of addiction. Recent animal studies suggest that peer presence can reduce cocaine intake, an influence potentially mediated, among others, by the subthalamic nucleus (STN). However, there is to date no...

The current study analyses laughter distribution, pragmatic use, and acoustic features in a multimodal conversation corpus, where one of the interlocutor had brain activity recorded with functional MRI. Particular focus is on the analysis of mimicking and non-mimicking laughter, as we hypothesized that the former might involve different neural path...

Humanoid robots might become more and more present in the most ordinary contexts of millions of people worldwide. Humans reason about these artificial agents mainly through the attribution of human characteristics, a process called anthropomorphism. However, despite number of studies, how we develop and structure the representation of non-human age...

Emotional contagion, in particular of happiness, is essential to creating social bonds. The somatic marker hypothesis posits that embodied physiological changes associated with emotions and relayed to the brain by the autonomous nervous system influence behavior. Perceiving others’ positive emotions should thus be associated with activity in brain...

Human–human interactions (HHI) and human–robot interactions (HRI) are compared to identify differences between cognitive processes reflecting bonding in social interactions with natural and artificial agents. We capitalize on a unique corpus of neuroimaging data (fMRI) recorded while participants freely discussed with another human or a conversatio...

In so-called ethorobotics and robot-supported social cognitive neurosciences, robots are used as scientific tools to study animal behavior and cognition. Building on previous epistemological analyses of biorobotics, in this article it is argued that these two research fields, widely differing from one another in the kinds of robots involved and in...

This article investigates the differences in cognitive and neural mechanisms between human-human and human-virtual agent interaction using a dataset recorded in an ecologically realistic environment. We use Convergent Cross Mapping (CCM) to investigate functional connectivity between pairs of regions involved in the framework of social cognitive ne...

The somatic marker hypothesis posits that perceiving emotions entails reenacting markers of self emotions, in particular in the autonomous nervous system. Well studied in decision-making tasks, it has not been tested in a social cognitive neuroscience framework, and in particular for the automatic processing of positive emotions during natural inte...

Humanoid robots are predicted to be increasingly present in the everyday life of millions of people worldwide. Humans make sense these artificial agents’ actions mainly through the attribution of human characteristics, a process called anthropomorphism. However, despite a large number of studies, how the representation of artificial agents is const...

Human-human and human-robot interaction are often compared with the overarching question of the differences in terms of cognitive processes engaged and what can explain these differences. However, research addressing this topic, especially in neuro-imagery, use extremely artificial interaction settings. Also, they neglect a crucial parameter of hum...

Human behaviors from toolmaking to language are thought to rely on a uniquely evolved capacity for hierarchical action sequencing. Testing this idea will require objective, generalizable methods for measuring the structural complexity of real-world behavior. Here we present a data-driven approach for extracting action grammars from basic ethograms,...

Human behaviors from tool-making to language are thought to rely on a uniquely evolved capacity for hierarchical action sequencing. Testing this idea will require objective, generalizable methods for measuring the structural complexity of real-world behavior. Here we present a data-driven approach for extracting action grammars from basic ethograms...

Introduction: The inability to extinguish a conditioned fear is thought to be at the core of post-traumatic stress disorder. Eye movement desensitization and reprocessing therapy has been efficacious for post-traumatic stress disorder, but the brain mechanisms underlying the effect are still unknown. The core effect of eye movement desensitization...

Background: Recent studies suggest that Posttraumatic Stress Disorder (PTSD) might be associated with dysfunctional reward circuitry. However, further research is needed to understand the key role of the reward system in PTSD symptomatology. Methods: Twenty participants with PTSD and 21 Trauma-Exposed matched Controls (TECs) completed the Monetary...

Multivariate pattern analysis (MVPA) has become vastly popular for analyzing functional neuroimaging data. At the group level, two main strategies are used in the literature. The standard one is hierarchical, combining the outcomes of within-subject decoding results in a second-level analysis. The alternative one, inter-subject pattern analysis, di...

Multivariate pattern analysis (MVPA) has become vastly popular for analyzing functional neuroimaging data. At the group level, two main strategies are used in the literature. The standard one is hierarchical, combining the outcomes of within-subject decoding results in a second-level analysis. The alternative one, inter-subject pattern analysis, di...

We present a novel functional magnetic resonance imaging paradigm for second-person neuroscience. The paradigm compares a human social interaction (human–human interaction, HHI) to an interaction with a conversational robot (human–robot interaction, HRI). The social interaction consists of 1 min blocks of live bidirectional discussion between the s...

We present an approach to objectify the social competence of artificial agents using human brain neurophysiology. Whole brain activity is recorded with functional Magnetic Resonance Imaging (fMRI) while participants discuss either with a human confederate or an artificial agent. This allows a direct comparison of local brain responses, including de...

Objective: Neurobiological models of Posttraumatic Stress Disorder (PTSD) implicate fear processing impairments in the maintenance of the disorder. Eye Movement Desensitization and Reprocessing (EMDR) is one of the most efficient psychotherapies to treat PTSD. We aimed at exploring the brain mechanisms of the fear circuitry involved in PTSD patient...

Assessing the social competence of anthropomorphic artificial agents developed to produce engaging social interactions with humans has become of primary importance to effectively compare various appearances and/or behaviours. Here we attempt to objectify the social competence of artificial agents, across different dimensions, using human brain neur...

Recognizing who is speaking is a cognitive ability characterized by considerable individual differences, which could relate to the inter-individual variability observed in voice-elicited BOLD activity. Since voice perception is sustained by a complex brain network involving temporal voice areas (TVAs) and, even if less consistently, extra-temporal...

The classical experimental methodology is ill-suited for the investigation of the behavioral and physiological correlates of natural social interactions. A new experimental approach combining a natural conversation between two persons with control conditions is proposed in this paper. Behavior, including gaze direction and speech, and physiology, i...

In this paper, we present a brief overview of our ongoing work about artificial interactive agents and their adaptation to users. Several possibilities to introduce humorous productions in a spoken dialog system are investigated in order to enhance naturalness during social interactions between the agent and the user. We finally describe our plan o...

Anthropomorphic artificial agents, computed characters or humanoid robots, can be sued to investigate human cognition. They are intrinsically ambivalent. They appear and act as humans, hence we should tend to consider them as human, yet we know they are machine designed by humans, and should not consider them as humans. Reviewing a number of behavi...

The workshop “Investigating Social Interactions With Artificial Agents” organized within the “International Conference on Multimodal Interactions 2017” attempts to bring together researchers from different fields sharing a similar interest in human interactions with other agents. If interdisciplinarity is necessary to address the question of the “T...

While several research works have shown that virtual agents are able to generate natural and social behaviors from users, few of them have compared these social reactions to those expressed dur- ing a human-human mediated communication. In this paper, we propose to explore the social cues expressed by a user during a mediated communication either w...

According to accounts of inter-speaker coordination based on internal predictive models, speakers tend to imitate each other each time they need to coordinate their behavior. According to accounts based on the notion of dynamical coupling, imitation should be observed only if it helps stabilizing the specific coordinative pattern produced by the in...

Sibling and friend relationships have significant impact on socio-emotional development. Hypothalamic supraoptic nucleus (SON) and paraventricular nucleus (PVN) are viable candidates in the formation and maintenance of these relationships through the synthesis and secretion of neuropeptides associated with attachment behaviors, including oxytocin....

In this paper, we propose that experimental protocols involving artificial agents, in particular the embodied humanoid robots, provide insightful information regarding social cognitive mechanisms in the human brain. Using artificial agents allows for manipulation and control of various parameters of behaviour, appearance and expressiveness in one o...

We introduce here a new experimental set-up that provides temporally aligned behavioral (including linguistic) together with physiological activity time-series recorded during social interactions. It brings the experimental approach closer to ecological social interactions while preserving important experimental features for transposing the set-up...

The hypothalamus is a brain structure containing multiple nuclei that mediate essential behavioral, autonomic, and endocrine functions including oxytocin synthesis. Oxytocin is a neuropeptide linked to complex social cognition and behaviors necessary for an effective social interaction. Oxytocinergic system dysfunction has been linked to social def...

Stone tools provide some of the most abundant, continuous, and high resolution evidence of behavioral change over human evolution, but their implications for cognitive evolution have remained unclear. We investigated the neurophysiological demands of stone toolmaking by training modern subjects in known Paleolithic methods ("Oldowan", "Acheulean")...

The present study investigated whether oculomotor behavior is influenced by attachment styles. The Relationship Scales Questionnaire was used to assess attachment styles of forty-eight voluntary university students and to classify them into attachment groups (secure, preoccupied, fearful, and dismissing). Eye-tracking was recorded while participant...

The anthropomorphic bias describes the finding that the perceived naturalness of a biological motion decreases as the human-likeness of a computer-animated agent increases. To investigate the anthropomorphic bias in autistic children, human or cartoon characters were presented with biological and artificial motions side by side on a touchscreen. Ch...

High-functioning individuals with Autism Spectrum Disorder (ASD) and age- and verbal IQ-matched controls (CTL) were fMRI scanned when playing “stone paper scissors”. They believed they were playing against three different opponents: a Human, a Robot endowed with an artificial intelligence attempting to win the game, and a Computer running a random...

Human ancestors first modified stones into tools 2.6 million years ago, initiating a cascading increase in technological complexity that continues today. A parallel trend of brain expansion during the Paleolithic has motivated over 100 years of theorizing linking stone toolmaking and human brain evolution, but empirical support remains limited. Our...

The current study was designed to investigate how the automatic spatial orientation of attention induced by the perception of another agent's orientation of attention is modulated by the social nature of the other agent. Modified versions of the Posner task, using a real or schematic face with eyes or head looking toward the left or the right befor...

Autism is a lifelong pervasive disorder of social cognition associated in particular with difficulties in joint attention, ie sharing the focus of attention to an object of the world with another agent. Care strategies that are expected to use artificial agents to support the intensive early intervention program to rehabilitate key aspects of norma...

The belief that artificial agents are useful interaction partners in cognitive therapies of social disorders such as autism fuels an increasing number of research projects involving the developments of robots and computer avatars. Yet, for an appropriate use of these new tools, it is necessary to understand how perception of and interaction with ar...

As social agents, humans continually interact with the people around them. Here, motor cooperation was investigated using a paradigm in which pairs of participants, one being scanned with fMRI, jointly controlled a visually presented object with joystick movements. The object oscillated dynamically along two dimensions, color and width of gratings,...

Mentalizing is defined as the inference of mental states of fellow humans, and is a particularly important skill for social interactions. Here we assessed whether activity in brain areas involved in mentalizing is specific to the processing of mental states or can be generalized to the inference of non-mental states by comparing brain responses dur...

Long-standing speculations and more recent hypotheses propose a variety of possible evolutionary connections between language, gesture and tool use. These arguments have received important new support from neuroscientific research on praxis, observational action understanding and vocal language demonstrating substantial functional/anatomical overla...

The adaptive threat-detection advantage takes the form of a preferential orienting of attention to threatening scenes. In this study, we compared attention to social scenes in 15 high-functioning individuals with autism (ASD) and matched typically developing (TD) individuals. Eye-tracking was recorded while participants were presented with pairs of...

Robotic devices, thanks to the controlled variations in their appearance and behaviors, provide useful tools to test hypotheses pertaining to social interactions. These agents were used to investigate one theoretical framework, resonance, which is defined, at the behavioral and neural levels, as an overlap between first- and third- person represent...

The perception of others' body movements is subserved by a network of lateral temporal, parietal, and premotor brain areas, here called the action perception system (APS). Using fMRI adaptation, we explored selectivity for biological motion and/or biological form in this network. Participants watched 2 s clips of recognizable actions of a human (bi...

Functional MRI signal was recorded while participants perceived stimuli presented using moving dots. In two conditions of interest, the motion of dots depicted intentions: dots representing the joints of an agent performing an action, and dots representing individual agents behaving contingently. The finding of a common cluster in the posterior par...

Using functional magnetic resonance imaging (fMRI) repetition suppression, we explored the selectivity of the human action perception system (APS), which consists of temporal, parietal and frontal areas, for the appearance and/or motion of the perceived agent. Participants watched body movements of a human (biological appearance and movement), a ro...

Paleolithic stone tools provide concrete evidence of major developments in human behavioural and cognitive evolution. Of particular interest are evolving cognitive mechanisms implied by the cultural transmission of increasingly complex prehistoric technologies, hypothetically including motor resonance, causal reasoning and mentalizing. To test the...

Objective: Although a large number of very preterm children follow a normal school cursus, they nevertheless present cognitive difficulties affecting visuo-spatial abilities especially. In this study, we investigated whether these visuo-spatial difficulties could originate in a dysfunction of the visual cerebral pathways (i.e., dorsal and ventral p...

Main effect of the human stimuli presentation (p<0.05 FDR-corrected, extend k>20, clusters are ordered by cortical lobes, then decreasing z coordinate), provided across the four types of actions and for each action independently. When available, functional localization is based on the anatomy toolbox (Eickhoff et al., 2005), with percentage indicat...

Experimental paradigm for participants in the fMRI experiment (details in main text). (0.43 MB MP4)

The humanoid robot WE4-RII was designed to express human emotions in order to improve human-robot interaction. We can read the emotions depicted in its gestures, yet might utilize different neural processes than those used for reading the emotions in human agents. Here, fMRI was used to assess how brain areas activated by the perception of human ba...

Here, we propose that bidirectionality in implicit motor coordination between humanoid robots and humans could enhance the social competence of human–robot interactions. We first detail some questions pertaining to human–robot interactions, introducing the Uncanny Valley hypothesis. After introducing a framework pertinent for the understanding of n...

Functional MRI was used to test predictions from a theory of the origin of human language. The gradual theory suggests that human language and tool-use skills have a similar hierarchical structure, and proposes that tool-manipulation skills are related to the origin and evolution of human language. Our results show an overlap of brain activity for...

We believe that humanoid robots provide new tools to investigate human social cognition, the processes underlying everyday interactions between individuals. Resonance is an emerging framework to understand social interactions that is based on the finding that cognitive processes involved when experiencing a mental state and when perceiving another...

The turn of the twenty-first century has seen a new era in the cognitive and brain sciences that allows us to address the age-old question of what it means to be human from a whole new range of different perspectives. Our knowledge of the workings of the human brain increases day by day and so does our understanding of the extended, distributed, em...

Stone tool-making is an ancient and prototypically human skill characterized by multiple levels of intentional organization. In a formal sense, it displays surprising similarities to the multi-level organization of human language. Recent functional brain imaging studies of stone tool-making similarly demonstrate overlap with neural circuits involve...

Being at the crux of human cognition and behaviour, imitation has become the target of investigations ranging from experimental psychology and neurophysiology to computational sciences and robotics. It is often assumed that the imitation is innate, but it has more recently been argued, both theoretically and experimentally, that basic forms of imit...

Archaeological and palaeontological evidence from the Early Stone Age (ESA) documents parallel trends of brain expansion and technological elaboration in human evolution over a period of more than 2Myr. However, the relationship between these defining trends remains controversial and poorly understood. Here, we present results from a positron emiss...

As humanoid robots are likely to become present in our societies, it is important to understand humans' reactions to these agents and to develop neuromimetic models of robots' motor learning. Motor resonance is an emerging framework based the overlap between neural processes involved in the execution and the perception of human actions. In this rev...

Computer-animated characters are common in popular culture and have begun to be used as experimental tools in social cognitive neurosciences. Here we investigated how appearance of these characters' influences perception of their actions. Subjects were presented with different characters animated either with motion data captured from human actors o...

In 1970, an eminent Japanese roboticist, Masahiro Mori, proposed the "uncanny valley" curve to describe the emotional response of humans to nonhuman agents. At the core of his proposal is the idea that as an agent is made more humanlike, the observer's familiarity does not linearly increase as one would intuit, but falls into a "valley of eeriness,...

Personal robots and robot technology (RT)-based assistive devices are expected to play a major role in our elderly-dominated society, with an active participation to joint works and community life with humans. In order to achieve this smooth and natural integration between humans and robots, interaction also at emotional level is a fundamental requ...

The appearance of the first intentionally modified stone tools over 2.5 million years ago marked a watershed in human evolutionary history, expanding the human adaptive niche and initiating a trend of technological elaboration that continues to the present day. However, the cognitive foundations of this behavioral revolution remain controversial, a...

As artificial anthropomorphic agents, such as humanoid robots and computer-generated characters, are likely to become widespread in our society, it is important to understand humans' emotional reactions to these agents. "Social resonance" is an emerging framework in social cognition covering cognitive processes used when experiencing an event and w...

As humanoid robots become more commonplace in our society, it is important to understand the relation between humans and humanoid robots. In human face-to-face interaction, the observation of another individual performing an action facilitates the execution of a similar action, and interferes with the execution of differmi action. This phenomenon h...

If humanoid robots are to become commonplace in our society, it is important to understand how they are perceived by humans. An influent model in social cognitive neuroscience posits that in human face-to-face interaction, the observation of another individual performing an action facilitates the execution of a similar action, and interferes with t...

Imitation is a vast topic for both human sciences and robotics. Recent advances in the understanding of the neural mechanisms of imitation offer methodologies that bring the two research domains closer. In this paper we analyze how an imitation system can be bootstrapped from a non-imitative system at an abstract level so that the ideas derived can...

Recent neuropsychological investigations of apraxia have led to new hypotheses about the representational defects associated with imitation impairments in neurological patients. This fMRI experiment investigated the relation between imitation and the body schema in healthy subjects. Experimental conditions were derived from a factorial plan, and pa...

Cooperation and competition are two basic modes of social cognition that necessitate monitoring of both one's own and others' actions, as well as adopting a specific mental set. In this fMRI, study individuals played a specially designed computer game, according to a set of predefined rules, either in cooperation with or in competition against anot...

There is converging evidence from developmental and cognitive psychology, as well as from neuroscience, to suggest that the self is both special and social, and that self-other interaction is the driving force behind self-development. We review experimental findings which demonstrate that human infants are motivated for social interactions and sugg...

Structural equation modelling was used to study the change of connectivity during a visual task with continuous variation of the attention load. The model was based on areas defined by the haemodynamic responses described elsewhere [Mazoyer, P., Wicker, B. & Fonlupt, P. (2002) A neural network elicited by parametric manipulation of the attention lo...

Positron emission tomography (PET) was used to investigate the neural correlates of feeling sympathy for someone else (i.e. the affinity, association, or relationship between persons wherein whatever affects one similarly affects the other). While undergoing PET scans, subjects were presented with a series of video-clips showing individuals (who we...

Agency is the sense that I am the one generating an action. In this neuroimaging experiment, subjects controlled a circle with a mouse while requested either to lead another circle (i.e., being the agent) or to follow it (i.e., being acted upon). Clusters within the right intraparietal sulcus were associated with following for the most rostral and...

Imitation is a natural mechanism involving perception-action coupling which plays a foundational role in human development, in particular to extract the intention from the surface behavior exhibited by others. The aim of this H(15)(2)O PET activation experiment was to investigate the neural basis of imitation of object-oriented actions in normal ad...

Imitation is a natural mechanism involving perception-action coupling which plays a central role in the development of understanding that other people, like the self, are mental agents. PET was used to examine the hemodynamic changes occurring in a reciprocal imitation paradigm. Eighteen subjects (a) imitated the actions of the experimenter, (b) ha...

A large body of psychophysical evidence suggests that perception of human movement is constrained by the observer's motor competence. PET measurements of regional cerebral blood flow were performed in eight healthy subjects who were requested, in a forced-choice paradigm, to anticipate the outcome of a single moving dot trajectory depicting the beg...

In recent years, neurophysiological evidence has accumulated in favor of a common coding between perception and execution of action. We review findings from recent neuroimaging experiments in the action domain with three complementary perspectives: perception of action, covert action triggered by perception, and reproduction of perceived action (im...