Showing papers by "Benoît G. Bardy published in 2013"

Getting Your Sea Legs

Abstract: Sea travel mandates changes in the control of the body. The process by which we adapt bodily control to life at sea is known as getting one's sea legs. We conducted the first experimental study of bodily control as maritime novices adapted to motion of a ship at sea. We evaluated postural activity (stance width, stance angle, and the kinematics of body sway) before and during a sea voyage. In addition, we evaluated the role of the visible horizon in the control of body sway. Finally, we related data on postural activity to two subjective experiences that are associated with sea travel; seasickness, and mal de debarquement. Our results revealed rapid changes in postural activity among novices at sea. Before the beginning of the voyage, the temporal dynamics of body sway differed among participants as a function of their (subsequent) severity of seasickness. Body sway measured at sea differed among participants as a function of their (subsequent) experience of mal de debarquement. We discuss implications of these results for general theories of the perception and control of bodily orientation, for the etiology of motion sickness, and for general phenomena of perceptual-motor adaptation and learning.

Social motor coordination in unaffected relatives of schizophrenia patients: a potential intermediate phenotype.

Abstract: Intermediate endophenotypes emerge as an important concept in the study of schizophrenia. Although research on phenotypes mainly investigated cognitive, metabolic or neurophysiological markers so far, some authors also examined the motor behavior anomalies as a potential trait-marker of the disease. However, no research has investigated social motor coordination despite the possible importance of its anomalies in schizophrenia. The aim of this study was thus to determine whether coordination modifications previously demonstrated in schizophrenia are trait-markers that might be associated with the risk for this pathology. Interpersonal motor coordination in 27 unaffected first-degree relatives of schizophrenia patients and 27 healthy controls was assessed using a hand-held pendulum task to examine the presence of interpersonal coordination impairments in individuals at risk for the disorder. Measures of neurologic soft signs, clinical variables and neurocognitive functions were collected to assess the cognitive and clinical correlates of social coordination impairments in at-risk relatives. After controlling for potential confounding variables, unaffected relatives of schizophrenia patients had impaired intentional interpersonal coordination compared to healthy controls while unintentional interpersonal coordination was preserved. More specifically, in intentional coordination, the unaffected relatives of schizophrenia patients exhibited coordination patterns that had greater variability and in which relatives did not lead the coordination. These results show that unaffected relatives of schizophrenia patients, like the patients themselves, also present deficits in intentional interpersonal coordination. For the first time, these results suggest that intentional interpersonal coordination impairments might be a potential motor intermediate endophenotype of schizophrenia opening new perspectives for early diagnosis.

Nonverbal expressive behaviour in schizophrenia and social phobia

Abstract: Expressive behaviour plays a crucial role in the success of social interactions. Abnormality of expressive behaviour has been reported in interpersonal interactions of patients suffering from schizophrenia and social phobia, two debilitating mental disorders with important social deficits. However, no study has compared the expressive behaviour in these two disorders. Thirty schizophrenia patients, 21 social phobia patients and 30 healthy controls were evaluated and compared on expressive, cognitive and clinical dimensions. Expressive behaviour was assessed using the Motor Affective subscale of the MotorAffective-Social-Scale (MASS). Covariables include the Positive and Negative Syndrome Scale (PANSS), the anxiety level Liebowitz-Social-Anxiety-Scale (LSAS) and cognitive tasks. After controlling for depression, schizophrenia and social phobia patients both exhibited significantly fewer expressive behaviours compared to healthy controls. Moreover, our results showed specific signatures: schizophrenia patients performed fewer spontaneous gestures (hand gestures and smiles) whereas social phobia patients had an impaired ability to produce voluntary smiles in comparison to healthy controls. Interestingly, poor social functioning was significantly correlated with a decrease of expressive behaviour for schizophrenia patients. Expressive behaviour is impaired in different ways in social phobia and schizophrenia and is associated in schizophrenia with poorer social functioning. The Motor Affective subscale of the MASS is an interesting tool for assessing the dysfunction of interpersonal expressive behaviour in mental disorders.

Virtual Reality as a Tool to Learn Interpersonal Coordination: Example of Team Rowing

Abstract: The success of interpersonal activities strongly depends on the coordination between our movements and those of others. Learning to coordinate with other people requires a long training time and is often limited by the difficulty of having people available at the same time and of giving them accurate and real-time feedback about their coordination. The goal of the present study was to determine in an indoor team rowing situation whether virtual-reality and motion-capture technologies can help the acquisition of interpersonal coordination. More specifically, we investigated the possibility for participants to (1) learn the skill of interpersonal coordination when training with a virtual teammate, (2) accelerate learning with real-time visual feedback, and (3) transfer this skill to synchronizing situations with a real teammate. Our results show that participants improved their coordination with both virtual and real teammates, and that this improvement was better for participants who received the ...

Design and evaluation of a multimodal virtual reality platform for rowing training

Abstract: Introduction............................................................................................................ 164 Sport.Training.in.Virtual.Reality............................................................................ 164 The.SPRINT.Platform............................................................................................ 165 Design................................................................................................................ 165 System................................................................................................................ 165 Orchestration...................................................................................................... 167 Training.Model.................................................................................................. 167 Protocol.Design................................................................................................. 168 Learning.Technique.Optimization.......................................................................... 168 Objective............................................................................................................ 168 Evaluation.......................................................................................................... 168 Accelerating.the.Management.of.Energetic.Resources.......................................... 170 Objective............................................................................................................ 170 Learning.Team.Coordination.Using.a.Virtual.Partner............................................ 172 Objective............................................................................................................ 172 Evaluation.......................................................................................................... 173 Perspectives.and.Conclusions................................................................................. 174 Acknowledgments.................................................................................................. 175 References.............................................................................................................. 175