Anxiety activating virtual environments for investigating social phobias

摘要

Social phobia has become one of the commonest manifestations of fear in any society. This fear is often accompanied by major depression or social disabilities. With the awareness that fear can be aggravated in social situations, virtual reality researchers and psychologists have investigated the feasibility of a virtual reality system as a psychotherapeutic intervention to combat social phobia. Virtual reality technology has rapidly improved over the past few years, making for better interactions. Nevertheless, the field of virtual reality exposure therapy for social phobia is still in its infancy and various issues have yet to be resolved or event uncovered. The key concept of virtual reality exposure therapy in the treatment of social phobia is based on its characteristic of perceptual illusion - the sense of presence - as an anxiety-activating system, instead of conventional imaginal or in-vivo exposure techniques. Therefore, in order to provoke a significant level of anxiety in virtual environments, it is very important to understand the impact of perceptual presence factors in virtual reality exposure therapy. Hence, this research mainly aims to investigate all the aspects of the correlation between anxiety and the components of the virtual environment in a computer-generated social simulation. By understanding this, this thesis aims to provide a framework for the construction of effective virtual reality exposure therapy for social phobia care which enables anxiety stimuli to be controlled in a gradual manner as a conventional clinical approach. This thesis presents a series of experimental studies that have been conducted with a common theme: the function of 3D inhabitants and visual apparatus in anxiety-activating virtual social simulation, a job-interview. However, each study is conducted using different research objectives. The experimental results are presented in this thesis, with psycho-physiological approach, revealing a variation of the distribution of participants' anxiety states across various VR conditions. The overall conclusion of this research is that an appropriate realism of VR stimuli is essential in sustaining the state of anxiety over the course of VR exposure. The high fidelity of virtual environment generally provoke a greater degree of anxiety, but this research also shows that aspects of VR fidelity is more related to the mental representation of individuals to the context of the stressful situation rather than any technology that is being used.