Biomedical subjects

Stéphane Bouchard

Publications and source records attributed to Stéphane Bouchard.

10 recordsLinked to original sources

PubMed2006

Temporal relationship between dysfunctional beliefs, self-efficacy and panic apprehension in the treatment of panic disorder with agoraphobia.

The aim of this study is to assess if changes in dysfunctional beliefs and self-efficacy precede changes in panic apprehension in the treatment of panic disorder with agoraphobia. Subjects participated in a larger study comparing the effectiveness of cognitive restructuring and exposure. Four variables were measured: (a) the strength of each subject's main belief toward the consequence of a panic attack; (b) perceived self-efficacy to control a panic attack in the presence of panicogenic body sensations; (c) perceived self-efficacy to control a panic attack in the presence of panicogenic thoughts; and (d) the level of panic apprehension of a panic attack. Variables were recorded daily on a "0" to "100" scale using category partitioning. Multivariate time series analysis and "causality testing" showed that, for all participants, cognitive changes preceded changes in the level of panic apprehension. Important individual differences were observed in the contribution of each variable to the prediction of change in panic apprehension. Changes in apprehension were preceded by changes in belief in three cases, by changes in self-efficacy in six cases, and by changes in both belief and self-efficacy in the remaining three cases. This pattern was observed in participants in the exposure condition as well as those in the cognitive restructuring condition. These results provide more empirical support to the hypothesis that cognitive changes precede improvement. They also underlie the importance of individual differences in the process of change. Finally, this study does not support the hypothesis that exposure and cognitive restructuring operate through different mechanisms, namely a behavioral one and a cognitive one.

Adult↗

PubMed2006

Effectiveness of virtual reality exposure in the treatment of arachnophobia using 3D games.

Buying or creating a virtual reality (VR) software is very costly. A less expensive alternative could be to modify already existing 3D computer games. The goal of this study is to assess the effectiveness of in virtuo exposure in the treatment of arachnophobia using modified 3D games. Participants were 10 women and 1 man. Virtual worlds were created using the game editor of a 3D computer game (Half-Life), modified to offer graduals hierarchies of fearful stimuli (spiders). Analyses revealed significant improvement between pre and post results on the behavioral avoidance test, the Spider Beliefs Questionnaire, and perceived self-efficacy. These promising results suggest that therapy using virtual reality exposure via a modified computer game is useful in the treatment of arachnophobia.

Adult↗

PubMed2005

Documenting the efficacy of virtual reality exposure with psychophysiological and information processing measures.

Many outcome studies have been conducted to assess the efficacy of virtual reality in the treatment of specific phobias. However, most studies used self-report data. The addition of objective measures of arousal and information processing mechanisms would be a valuable contribution in order to validate the usefulness of virtual reality in the treatment of anxiety disorders. The goal of this study was to document the impact of virtual reality exposure (VRE) on cardiac response and automatic processing of threatening stimuli. Twenty-eight adults suffering from arachnophobia were assessed and received an exposure-based treatment using virtual reality. General outcome and specific processes measures included a battery of standardized questionnaires, a pictorial emotional Stroop task, a behavioral avoidance test and a measure of participants' inter-beat intervals (IBI) while they were looking at a live tarantula. Assessment was conducted before and after treatment. Repeated measures ANOVAs revealed that therapy had a positive impact on questionnaire data, as well as on the behavioral avoidance test. Analyses made on the pictorial Stroop task showed that information processing of spider-related stimuli changed after treatment, which also indicates therapeutic success. Psychophysiological data also showed a positive change after treatment, suggesting a decrease in anxiety. In sum, VRE led to significant therapeutic improvements on objective measures as well as on self-report instruments.

Adult↗

PubMed2005

Scene perception, gaze behavior, and perceptual learning in virtual environments.

More and more immersive environments are developed to provide support for learning or training purposes. Ecological validity of such environments is usually based on learning performance comparisons between virtual environments and their genuine counterparts. Little is known about learning processes occurring in immersive environments. A new technique is proposed for testing perceptual learning during virtual immersion. This methodology relies upon eye-tracking technologies to analyze gaze behavior recorded in relation to virtual objects' features and tasks' requirements. It is proposed that perceptual learning mechanisms engaged could be detected through eye movements. In this study, nine subjects performed perceptual learning tasks in virtual immersion. Results obtained indicated that perceptual learning influences gaze behavior dynamics. More precisely, analysis revealed that fixation number and variability in fixation duration varied with perceptual learning level. Such findings could contribute in shedding light on learning mechanisms as well as providing additional support for validating virtual learning environments.

Adult↗

PubMed2004

Delivering cognitive-behavior therapy for panic disorder with agoraphobia in videoconference.

Delivering psychotherapy by videoconference could significantly increase the accessibility of empirically validated treatments. The aim of this study was to compare the effectiveness of cognitive-behavior therapy (CBT) for panic disorder with agoraphobia (PDA) when the therapy is delivered either face-to-face or by videoconference. A sample of 21 participants was treated either face-to-face or by videoconference. Results showed that CBT delivered by videoconference was as effective as CBT delivered face-to-face. There was a statistically significant reduction in all measures, and the number of panic-free participants among those receiving CBT by videoconference was 81% at post-treatment and 91% at the 6-month follow-up. None of the comparisons with face-to-face psychotherapy suggested that CBT delivered by videoconference was less effective. These results were confirmed by analyses of effect size. The participants reported the development of an excellent therapeutic alliance in videoconference as early as the first therapy session. The importance of these results for treatment accessibility is discussed. Hypotheses are proposed to explain the rapid creation of strong therapeutic alliances in videoconferencing.

Adult↗

PubMed2004

The challenge of using virtual reality in telerehabilitation.

Continuing advances in virtual reality (VR) technology along with concomitant system cost reductions have supported the development of more useful and accessible VR systems that can uniquely target a wide range of physical, psychological, and cognitive rehabilitation concerns and research questions. VR offers the potential to deliver systematic human testing, training, and treatment environments that allow for the precise control of complex dynamic three-dimensional stimulus presentations, within which sophisticated interaction, behavioral tracking, and performance recording is possible. The next step in this evolution will allow for Internet accessibility to libraries of VR scenarios as a likely form of distribution and use. VR applications that are Internet deliverable could open up new possibilities for home-based therapy and rehabilitation. If executed thoughtfully, they could increase client involvement, enhance outcomes and reduce costs. However, before this vision can be achieved, a number of significant challenges will need to be addressed and solved. This article will first present three fictional case vignettes that illustrate the ways that VR telerehabilitation might be implemented with varying degrees of success in the future. We then describe a system that is currently being used to deliver virtual worlds over the Internet for training safety skills to children with learning disabilities. From these illustrative fictional and reality-based applications, we will then briefly discuss the technical, practical, and user-based challenges for implementing VR telerehabilitation, along with views regarding the future of this emerging clinical application.

Adult↗

PubMed2003

Anxiety and presence during VR immersion: a comparative study of the reactions of phobic and non-phobic participants in therapeutic virtual environments derived from computer games.

Virtual reality can be used to provide phobic clients with therapeutic exposure to phobogenic stimuli. However, purpose-built therapeutic VR hardware and software can be expensive and difficult to adapt to individual client needs. In this study, inexpensive and readily adaptable PC computer games were used to provide exposure therapy to 13 phobic participants and 13 non-phobic control participants. It was found that anxiety could be induced in phobic participants by exposing them to phobogenic stimuli in therapeutic virtual environments derived from computer games (TVEDG). Assessments were made of the impact of simulator sickness and of sense of presence on the phobogenic effectiveness of TVEDGs. Participants reported low levels of simulator sickness, and the results indicate that simulator sickness had no significant impact on either anxiety or sense of presence. Group differences, correlations, and regression analyses indicate a synergistic relationship between presence and anxiety. These results do not support Slater's contention that presence and emotion are orthogonal.

Adolescent↗

PubMed2003

Eye-tracking in immersive environments: a general methodology to analyze affordance-based interactions from oculomotor dynamics.

This paper aims at presenting a new methodology to study how perceptual and motor processes organized themselves in order to achieve invariant visual information picking-up in virtual immersions. From a head-mounted display, head and eye movements were recorded using tracking devices (magnetic and infrared) that render the six degrees-of-freedom associated with the position and orientation of head movements, and two degrees-of-freedom from one eye. We measured the continuous line of sight's deviation from a pre-selected area on a virtual stimulus. Some preliminary analyses of the dynamical properties of the emergent perceptual and motor patterns are presented as they are considered to be representative of the process of affordance extraction.

Adaptation, Physiological↗

PubMed2002

Measuring sexual preferences in virtual reality: a pilot study.

Virtual reality (VR), as a method to assess sexual preferences, is explored. Dynamics of the subjective point of view (POV), subjective affective state, and feeling of presence, as measured following the interaction with a virtual naked model, appear as promising ways to probe sexual preferences as expressed in immersion. Theoretical aspects of VR psychology and further steps in developing a sexual preferences assessment method are delineated.

Adult↗

PubMed2002

Behavioral avoidance dynamics in the presence of a virtual spider.

Tracking behavior with a virtual spider and a neutral target is compared in fearful and nonfearful subjects. Head-tracking in virtual environments appears to be a scale-free behavior with long-range fractal-like patterns. Moreover, these fractal patterns change according to what the target affords the tracker and the level of behavioral avoidance manifested by the subjects. Results are interpreted in terms of ecological psychology and nonlinear dynamics, and implications for virtual reality (VR) psychology are outlined.

Adult↗