Benoît G. Bardy

• Professor
• Professor (Full) at Université de Montpellier

Abstract Extended Reality (XR) and Artificial Intelligence (AI) are redefining human-computer interaction (HCI), offering both unprecedented accessibility benefits and significant ethical challenges. This study applies futurecasting, synthesising insights from XR scientists in the SHARESPACE.EU project to anticipate risks and propose solutions for...

Optic flow can significantly influence the perception and exertion of effort. In this study, we investigated the effects of exposure to proximal and distal areas of the optic flow field on exerted and perceived cycling effort. Thirty cyclists participated in two 20-minute cycling trials within a virtual reality environment, with the goal of surpass...

A commonly used definition of spatial disorientation (SD) in aviation is ''an erroneous sense of one's position and motion relative to the plane of the earth's surface''. There exists a wide range of SD use-cases dictated by situational factors, therefore SD has been predominantly studied using reduced motion detection experimental contexts in isol...

Data on gait parameters during real-life activities and home rehabilitation programs for Persons with Parkinson's disease (PwPDs) are scarce. Although cueing has been shown to improve their gait in laboratory conditions, few studies have applied this technique in at-home rehabilitation programs. Our study aimed to explore the use of a real-time syn...

J. J. Gibson (1966) rejected many classical assumptions about perception but retained 1 that dates back to classical antiquity: the assumption of separate senses. We suggest that Gibson's retention of this assumption compromised his novel concept of perceptual systems. We argue that lawful, 1:1 specification of the animal--environment interaction,...

This paper compares methods for scoring the synchronization between music and motion. A wide range of local and global methods such as the Gaussian-based method, relative phase, and dynamic time warping (DTW) have been evaluated. Firstly, these methods were tested on synthetic data representing various scenarios of motion and music interaction. Sec...

Innovative applications of human movement analysis, for example, for mitigating/slowing down certain pathological conditions, have recently emerged from the modeling and automated measurement of full-body expressive midlevel individual and group movement qualities, at a higher complexity level than movement qualities derived directly from physical...

Introduction Walking indoors, particularly at home, presents a distinct experience compared to the conventional pedestrian walking classically described. Our homes encompass intricate, confined, and cluttered architectural spaces that necessitate a predominantly curvilinear walking pattern. Despite the growing interest in studying our home, spurred...

Emotions play a fundamental role in human interactions and trigger responses in physiological, psychological, and behavioral modalities. Interpersonal coordination often entails attunement between individuals in various modalities. Previous research has elucidated the mechanisms of interpersonal synchronization and the emotions aroused by joint act...

Parkinson's disease (PD) is associated with reduced coordination abilities. These can result either in random or rigid patterns of movement. The latter, described here as coordination rigidity (CR), have been studied less often. We explored whether CR was present in gait, quiet stance, and speech-tasks involving coordination among multiple joints a...

The ability to synchronise with other people is a core socio-motor competence acquired during human development. In this study we aimed to understand the impact of individual emotional arousal on joint action performance. We asked 15 mixed-gender groups (of 4 individuals each) to participate in a digital, four-way movement synchronisation task. Par...

Emotions are a natural vector for acting together with others and are witnessed in human behaviour, perception and body functions. For this reason, studies of human-to-human interaction, such as multi-person motor synchronisation, are a perfect setting to disentangle the linkage of emotion with socio-motor interaction. And yet, the majority of join...

Future vertical lift (FVL) missions will be characterized by increased agility, degraded visual environments (DVE) and optionally piloted vehicles (OPVs). Increased agility will induce more frequent variations of linear and angular accelerations, while DVE will reduce the structure and quality of the out-the-window (OTW) scene. As rotorcrafts becom...

Thanks to various technological progresses such as musical rhythm estimation and motion capture systems, the evaluation of synchronization performances between motion and music beats is today possible. In this paper, we propose an innovative playful method to assess synchronization between hand motion and music. In this application, the hand gestur...

Movement dataset reviews exist but are limited in coverage, both in terms of size and research discipline. While topic-specific reviews clearly have their merit, it is critical to have a comprehensive overview based on a systematic survey across disciplines. This enables higher visibility of datasets available to the research communities and can fo...

Research in joint action focuses on the psychological, neurological, and physical mechanisms by which humans collaborate with other agents, and overlaps with several domains related to human-robot interaction. The development of artificial systems that can support or emulate the requisite aspects of joint action could lead to improved human-robot t...

In human groups performing oscillatory tasks, it has been observed that the frequency of participants' oscillations reduces when compared to that acquired in solo. This experimental observation is not captured by the standard Kuramoto oscillators, often employed to model human synchronization. In this work, we aim at capturing this observed phenome...

Thanks to various technological progresses such as musical rhythm estimation and motion capture systems, the evaluation of synchronization performances between motion and music beats is today possible. In this paper, we propose an innovative playful method to assess synchronization between hand motion and music. In this application, the hand gestur...

A commonly used definition of spatial disorientation (SD) in aviation is “an erroneous sense of one’s position and motion relative to the plane of the earth’s surface”. There exists a wide range of SD use-cases dictated by situational factors, therefore SD has been predominantly studied using reduced motion detection experimental contexts in isolat...

Walking at home can provide valuable information about locomotor efficiency, anticipation of daily hazards and general well-being. Here, we present a multidisciplinary method to reconstruct locomotor trajectories while walking at home with a capacitive proximity sensing device — the SensFloor — which was installed in a real occupied apartment in th...

Synchronization of human networks is fundamental in many aspects of human endeavour. Recently, much research effort has been spent on analyzing how motor coordination emerges in human groups (from rocking chairs to violin players) and how it is affected by coupling structure and strength. Here we uncover the spontaneous emergence of leadership (bas...

Our daily human life is filled with a myriad of joint action moments, be it children playing, adults working together (i.e., team sports), or strangers navigating through a crowd. Joint action brings individuals (and embodiment of their emotions) together, in space and in time. Yet little is known about how individual emotions propagate through emb...

Our daily human life is filled with a myriad of joint action moments, be it children playing, adults working together (i.e., team sports), or strangers navigating through a crowd. Joint action brings individuals (and embodiment of their emotions) together, in space and in time. Yet little is known about how individual emotions propagate through emb...

Bodily expression of felt emotion has been documented in the literature. However, it is often associated with high motor variability between individuals. This study aimed to identify individual motor signature (IMS) of emotions. IMS is a new method of motion analysis and visualization able to capture the subtle differences in the way each of us mov...

Future vertical lift (FVL) missions will be characterized by increased agility, degraded visual environments (DVE) and optionally piloted vehicles (OPVs). Increased agility will induce more frequent variations of linear and angular accelerations, while DVE will reduce the structure and quality of the out-the-window (OTW) scene. As rotorcrafts becom...

Taking regular walks when living with Parkinson’s disease (PD) has beneficial effects on movement and quality of life. Yet, patients usually show reduced physical activity compared to healthy older adults. Using auditory stimulation such as music can facilitate walking but patients vary significantly in their response. An individualized approach ad...

Low-Altitude Flight (LAF) is a flight formation consisting of rapid close ground flight. Perception and control of self-motion, allowing for optimal information collection and rapid adaptation, are of fundamental importance during LAF, but remain largely unexplored. This study aimed to analyse the impact of visuo-vestibular stimuli on the monitorin...

For more than 4 decades, it has been shown that humans are particularly sensitive to biological motion and extract socially relevant information from it such as gender, intentions, emotions or a person’s identity. A growing number of findings, however, indicate that identity perception is not always highly accurate, especially due to large inter-in...

The article Decoding identity from motion: how motor similarities colour our perception of self and others, written by Alexandre Coste, Benoît G, Bardy, Stefan Janaqi, Piotr Słowiński, Krasimira Tsaneva-Atanasova, Juliette Lozano Goupil, Ludovic Marin, was originally published electronically on the publisher's internet portal on 6th February 2020,...

Human rhythmic movements spontaneously synchronize with auditory rhythms at various frequency ratios. The emergence of more complex relationships—for instance, frequency ratios of 1:2 and 1:3—is enhanced by adding a congruent accentuation pattern (binary for 1:2 and ternary for 1:3), resulting in a 1:1 movement–accentuation relationship. However, t...

Humans spontaneously synchronize their movements with external auditory rhythms such as a metronome or music. Although such synchronization preferentially occurs toward a simple 1:1 movement–sound frequency ratio, the parameters facilitating spontaneous synchronization to more complex frequency ratios remain largely unclear. The present study inves...

Abstract Humans interact in groups through various perception and action channels. The continuity of interaction despite a transient loss of perceptual contact often exists and contributes to goal achievement. Here, we study the dynamics of this continuity, in two experiments involving groups of participants ( $$N=7$$ N = 7 ) synchronizing their mo...

Objective: We aimed to identify timing distortions in production and perception of rhythmic events in patients with idiopathic REM sleep behavior disorder (iRBD) as early markers of Parkinson's disease (PD). Methods: Rhythmic skills, clinical characteristics, dysautonomia, depression, and olfaction were compared in 97 participants, including 21...

Improvisation is not limited to the performing arts, but is extended to everyday life situations such as conversations and decision-making. Due to their ubiquitous nature, improvisation skills have received increasing attention from researchers over the last decade. A core challenge is to grasp the complex creative processes involved in improvisati...

Theorists have long postulated that facial properties such as emotion and sex are potent social stimuli that influence how individuals act. Yet extant scientific findings were mainly derived from investigations on the prompt motor response upon the presentation of affective stimuli, which were mostly delivered by means of pictures, videos, or text....

People walking side by side spontaneously synchronize their steps on some occasions but not on others, which poses a challenge to theories of perception-action based on interactive dynamic systems. How can action be spontaneously entrained by some sources of perceptual information while others are selectively ignored? The predictive processing fram...

Humans spontaneously synchronize their movements with external auditory rhythms such as a metronome or music. Although such synchronization preferentially occurs toward simple 1:1 movement-stimulus frequency ratio, the extent to which spontaneous synchronization can also occur toward more complex frequency ratios remains largely unclear. The presen...

Synchronization of behavior such as gestures or postures is assumed to serve crucial functions in social interaction but has been poorly studied to date in schizophrenia. Using a virtual collaborative environment (VCS), we tested 1) whether synchronization of behavior, i.e., the spontaneous initiation of gestures that are congruent with those of an...

Introduction/Background Rhythmic auditory cues can immediately improve gait in Parkinson's disease. However, this effect varies considerably across patients. The factors associated with this individual variability are not known to date. Patients’ rhythmic abilities and musicality (e.g., perceptual and singing abilities, emotional response to music,...

Bousquet J, Bourret R, Camuzat T, Augé P, Bringer J, Noguès M, Jonquet O, de la Coussaye JE, Ankri J, Cesari M, Guérin O, Vellas B, Blain H, Arnavielhe S, Avignon A, Combe B, Canovas G, Daien C, Dray G, Dupeyron A, Jeandel C, Laffont I, Laune D, Marion C, Pastor E, Pélissier JY, Galan B, Reynes J, Reuzeau JC, Bedbrook A, Granier S, Adnet PA, Amouya...

Gait dysfunctions in Parkinson's disease can be partly relieved by rhythmic auditory cueing. This consists in asking patients to walk with a rhythmic auditory stimulus such as a metronome or music. The effect on gait is visible immediately in terms of increased speed and stride length. Moreover, training programs based on rhythmic cueing can have l...

Rhythmic auditory cues can immediately improve gait in Parkinson’s disease. However, this effect varies considerably across patients. The factors associated with this individual variability are not known to date. Patients’ rhythmic abilities and musicality (e.g., perceptual and singing abilities, emotional response to music, and musical training) m...

EuroMov est un centre de recherche multidisciplinaire sur le mouvement humain situé à Montpellier, en France ; les chercheurs étudient une grande variété de comportements humains, en particulier, la posture et le mouvement, en utilisant des principes d’analyse de divers domaines de l’ingénierie, des mathématiques et des sciences du mouvement, cogni...

Contexte L’indiçage rythmique auditif peut améliorer la marche de façon immédiate au cours de la maladie de Parkinson (MP). Cependant, cet effet varie considérablement parmi les patients, pouvant même parfois être délétère chez certains. Les facteurs associés à la variabilité de cette réponse ne sont pas connus à ce jour. Les compétences rythmiques...

Contexte Les patients souffrant de la maladie de Parkinson (MP) présentent des déficits dans la sphère du rythme, largement documentés. Ils ont des difficultés dans la discrimination perceptuelle de rythmes auditifs et dans la synchronisation du mouvement avec des stimuli rythmiques (métronomes ou musique). Cependant, nous ne savons pas jusqu’ici s...

Rapid progress in the area of humanoid robots offers tremendous possibilities for investigating and improving social competences in people with social deficits, but remains yet unexplored in schizophrenia. In this study, we examined the influence of social feedbacks elicited by a humanoid robot on motor coordination during a human-robot interaction...

Although existing studies indicate a positive effect of interpersonal motor coordination (IMC) on likability, no consensus has been reached as for the effect of likability back onto IMC. The present study specifically investigated the causal effect of likability on IMC and explored, by tracking the natural gaze direction, the possible underlying me...

An important open problem in Human Behaviour is to understand how coordination emerges in human ensembles. This problem has been seldom studied quantitatively in the existing literature, in contrast to situations involving dual interaction. Here we study motor coordination (or synchronisation) in a group of individuals where participants are asked...

The dynamics of postural motion has been studied for decades, and the principal laws for postural control shared by all human beings have been derived. Yet, differences among individuals exist in the way people stand or move. Usually regarded as a source of noise, inter-individual variability (i.e., dissimilarity from person to person) is an outsta...

J. J. Gibson (1966) rejected many classical assumptions about perception but retained 1 that dates back to classical antiquity: the assumption of separate senses. We suggest that Gibson's retention of this assumption compromised his novel concept of perceptual systems. We argue that lawful, 1:1 specification of the animal–environment interaction, w...

Spontaneous synchronization is defined as the entrainment of human movement to a rhythmic stimulus without any instruction to do so (Repp & Su, 2013). Studies have shown that listening to an auditory rhythm can modulate the tempo of our own periodic movements, such as tapping, or rocking in a rocking chair (Demos et al. 2012; Hattori et al., 2015)....

Mirror game test could detect schizophrenia A new test of movement and social interaction could detect markers of schizophrenia, and help to diagnose and manage the condition. In an effort to establish reliable indicators of schizophrenia, Piotr Slowinski at the University of Exeter, UK and colleagues developed a test that could detect deficits in...

Human interaction often relies on socio-motor improvisation. Creating unprepared movements during social interaction is not a random process but relies on rules of synchronization. These situations do not only involve people to be coordinated, but also require the adjustment of their posture in order to maintain balance and support movements. The p...

Abstract: Background: The use of humanoid robots to play a therapeutic role in helping individuals with social disorders such as autism is a newly emerging field, but remains unexplored in schizophrenia. As the ability for robots to convey emotion appear of fundamental importance for human-robot interactions, we aimed to evaluate how schizophrenia...

Stride durations in gait exhibit long-range correlation (LRC) which tends to disappear with certain movement disorders. The loss of LRC has been hypothesized to result from a reduction of functional degrees of freedom of the neuromuscular apparatus. A consequence of this theory is that environmental constraints such as the ones induced during const...

An important open problem in Human Behaviour is to understand how coordination emerges in human ensembles. This problem has been seldom studied quantitatively in the existing literature, in contrast to situations involving dual interaction. Here we study motor coordination (or synchronisation) in a group of individuals where participants are asked...

Background: The ability to follow one another's gaze plays an important role in our social cognition; especially when we synchronously perform tasks together. We investigate how gaze cues can improve performance in a simple coordination task (i.e., the mirror game), whereby two players mirror each other's hand motions. In this game, each player is...

An example of desired trajectories for the avatar’s hand and gaze in two conditions. (EPS)

The results of the Repeated Measures ANOVA. In each condition (i.e., gaze cue and no-gaze cue), the three different measurements done are: 1) the reaction time, 2) the perception of the difficulty of the game, and 3) the perception of the human-similarity. In Model I, the effects of conditions and the order of the conditions are studied. In Model I...

Equality of variances. The Levene’s test of equality of error variances for Model I and Model II presented in S3 Table. For both models df1 = 28 and df2 = 8. (EPS)

Parameters used in the iCub gaze controller. (EPS)

The RT in gaze cue condition vs. attention. The RTg distribution of participants who found it hard to divide their attention between the avatar’s gaze and hand compared to the rest of the participants. The ANOVA analysis in S7 Table showed that the difference in these distributions is significant. (EPS)

The questionnaire used in this study. (EPS)

The split performed on age for the ANOVA analysis. (EPS)

Participants’ attentional workload. The distribution obtained from the answers to the questionnaire concerning the division of attention between avatar’s gaze and hand. (EPS)

Correlation between cooperation and realism. Contingency table for effect of gaze cues on participants’ opinion on the difficulty of the interaction and the realism of the avatar. (EPS)

Crosschecking the result of the motion capture (i.e., RT) with the result of the questionnaire using repeated measures ANOVA. In Model I, the effect of perception of difficulty on RT is studied. Diff_dummy is 0 for the participants who found it harder to follow the avatar with gaze cue, and 1 for the rest of the participants. In Model II, the effec...