Over the past twenty years, new types of exposure therapy using virtual reality technologies have been developed for the treatment and rehabilitation of emotional disorders, including phobias. Virtual Reality (VR) offers a very powerful control of the sensory and spatial presentation of stimuli, allowing better control of the emotional impact of anxiety-inducing situations to which the patient is exposed. However, in order to exploit these unique benefits of VR, more knowledge is needed about the links between the presentation characteristics of stimuli and their emotional effect.
We explored these links in virtual crowds. Fear of crowds is a symptom found in several emotional disorders (agoraphobia, social phobia, fear of falling...) and has both sensory (auditory and visual) and spatial components, making crowds an ideal stimulus for our studies.
A study was conducted on two groups of participants (with a fear of crowds or not), immersed in a visuo-auditory environment containing virtual crowds, who were asked to indicate the intensity of their discomfort.
The sensory presentation of the crowds was either visual or auditory, or both visual and auditory. The results indicate that the visual-auditory presentation amplified negative feelings in participants who were sensitive to crowd fear. However, this effect was only observed when the crowd was close to the participant. This result reveals the interaction of the spatial and sensory characteristics of the anxiogenic stimulus on the emotional impact.
This spatial dependence has motivated the initiation of a research component devoted to the study of peri-personal space. Humans do not perceive space in a homogeneous way: the brain codes space close to the body differently from far space. Peri-personal space (near the body) is coded by multisensory neurons. We seek to highlight the plasticity of the limits of this space according to the nature of the sound and the emotional or social context.
IRCAM's Team : Acoustic and Cognitive Spaces
VR device in IRCAM’s studio 4. Visual stereo is projected on a large screen. The visual and auditory information is updated by a position tracking system.