Showing papers by "Benoît G. Bardy published in 2014"

Difficulty leading interpersonal coordination: towards an embodied signature of social anxiety disorder

Abstract: Defined by a persistent fear of embarrassment or negative evaluation while engaged in social interaction or public performance, social anxiety disorder (SAD) is one of the most common psychiatric syndromes. Previous research has made a considerable effort to better understand and assess this mental disorder. However, little attention has been paid to social motor behavior of patients with SAD despite its crucial importance in daily social interactions. Previous research has shown that the coordination of arm, head or postural movements of interacting people can reflect their mental states or feelings such as social connectedness and social motives, suggesting that interpersonal movement coordination may be impaired in patients suffering from SAD. The current study was specifically aimed at determining whether SAD affects the dynamics of social motor coordination. We compared the unintentional and intentional rhythmic coordination of a SAD group (19 patients paired with control participants) with the rhythmic coordination of a control group (19 control pairs) in an interpersonal pendulum coordination task. The results demonstrated that unintentional social motor coordination was preserved with SAD while intentional coordination was impaired. More specifically, intentional coordination became impaired when patients with SAD had to lead the coordination as indicated by poorer (i.e., more variable) coordination. These differences between intentional and unintentional coordination as well as between follower and leader roles reveal an impaired coordination dynamics that is specific to SAD, and thus, opens promising research directions to better understand, assess and treat this mental disorder.

Energy management using virtual reality improves 2000-m rowing performance

Abstract: Elite-standard rowers tend to use a fast-start strategy followed by an inverted parabolic-shaped speed profile in 2000-m races This strategy is probably the best to manage energy resources during the race and maximise performance This study investigated the use of virtual reality (VR) with novice rowers as a means to learn about energy management Participants from an avatar group (n = 7) were instructed to track a virtual boat on a screen, whose speed was set individually to follow the appropriate to-be-learned speed profile A control group (n = 8) followed an indoor training programme In spite of similar physiological characteristics in the groups, the avatar group learned and maintained the required profile, resulting in an improved performance (ie a decrease in race duration), whereas the control group did not These results suggest that VR is a means to learn an energy-related skill and improve performance

Influence of stimulus velocity profile on rhythmic visuomotor coordination.

Abstract: Every day, we visually coordinate our movements with environmental rhythms. Despite its ubiquity, it largely remains unclear why certain visual rhythms or stimuli facilitate such visuomotor coordination. The goal of the current study was to investigate whether the velocity profile of a rhythmic stimulus modulated the emergence and stability of this coordination. We examined both intended (Experiment 1) and unintended or spontaneous coordination (Experiment 2) between the rhythmic limb movements of participants and stimuli exhibiting different velocity profiles. Specifically, the stimuli oscillated with either a sinusoidal (harmonic), nonlinear Rayleigh, or nonlinear Van der Pol velocity profile, all of which are typical of human or biological rhythmic movement. The results demonstrated that the dynamics of both intended and unintended visuomotor coordination were modulated by the stimulus velocity profile, and that the Rayleigh velocity profile facilitated the coordination, suggesting a crucial role of the slowness to the endpoints or turning points of the stimulus trajectory for stable coordination. More generally, these findings open promising research directions to better understand and improve coordination with artificial agents and people with social deficits.

Just the sight of you: postural effects of interpersonal visual contact at sea.

Abstract: The control of standing body posture is affected by mechanical perturbations, such as motion of the support surface. Postural activity also is responsive to subtle social factors: When 2 people interact there is spontaneous interpersonal coordination of their movements. We asked whether interpersonal postural coordination based on visual contact would be robust in the presence of mechanical perturbations that characterize sea travel. During an ocean voyage, pairs of participants stood facing together or facing apart. Interpersonal coordination of body sway was stronger when participants faced each other than when they faced apart. Furthermore, overall body movement was reduced when individuals faced together, suggesting that the sight of another person improved individuals' ability to compensate for ship motion. These findings provide the first evidence that the "soft" constraint of interpersonal visual contact can influence interpersonal postural coordination as people simultaneously adjust postural sway in response to powerful mechanical (i.e., "hard") constraints.

Movement similarities and differences during social interaction: The scientific foundation of the ALTEREGO European project

Abstract: Schizophrenia, autism, or social phobia are typically accompanied by social interaction deficits. The objective of the AlterEgo European project is the creation of an interactive cognitive architecture, implementable in various artificial agents, allowing a continuous interaction with patients suffering from social disorders by virtue of changes in behavioral (robot-based) as well as morphological (avatar-based) properties of that agent. Here we present the scientific foundations of the project and its four main experimental steps. The results of the first similarity experiments are reported, which show that healthy participants functionally adapt their social motor interaction when they interact with agents (real or artificial) morphologically and behaviorally similar to, or different from, them. These results obtained with healthy participants have consequences for the rehabilitation of socially deficient patients.

Social priming increases nonverbal expressive behaviors in schizophrenia

Abstract: Semantic priming tasks are classically used to influence and implicitly promote target behaviors. Recently, several studies have demonstrated that prosocial semantic priming modulated feelings of social affiliation. The main aim of this study was to determine whether inducing feelings of social affiliation using priming tasks could modulate nonverbal social behaviors in schizophrenia. We used the Scrambled Sentence Task to prime schizophrenia patients according to three priming group conditions: pro-social, non-social or anti-social. Forty-five schizophrenia patients, diagnosed according to DSM-IV-TR, were randomly assigned to one of the three priming groups of 15 participants. We evaluated nonverbal social behaviors using the Motor-Affective subscale of the Motor-Affective-Social-Scale. Results showed that schizophrenia patients with pro-social priming had significantly more nonverbal behaviors than schizophrenia patients with anti-social and non-social priming conditions. Schizophrenia patient behaviors are affected by social priming. Our results have several clinical implications for the rehabilitation of social skills impairments frequently encountered among individuals with schizophrenia.