Development of a Photo-realistic Virtual Reality Exposure Therapy System using Smartphone

Abstract

Exposure therapy has been used as one of the effective tool to treat anxiety disorder in several studies. As one of the tool for enhancing the effectiveness of exposure therapy, Virtual Reality (VR) has been used in some studies, and this combination has been called Virtual Reality Exposure Therapy (VRET). VRET had a greater effectiveness in anxiety disorder, compared from conventional in-vivo exposure therapy which means exposure therapy with stimuli in real world. Photo-realistic Virtual Environments (VEs) is the methodology of virtual reality based on capturing environments, instead of modeling virtual objects. It has been used as one of the important tool for exposure therapy. Photo-realistic VEs have been using spherical texture for 360-degree full immersive view of virtual environments. Conventional studies for VRET with photo-realistic VEs used expensive device with experts, but current smartphone can operate virtual reality with its own computing power and simple head-mounted display (HMD) with relative cheap price. Moreover, capturing device or mobile application like Google Street View for photo-realistic VEs can make spherical texture of the environment with simple process. However, research of photo-realistic VRET using mobile devices as a tool for exposure therapy was hardly found, despite mobile device has a benefit for photo-realistic VRET. This study suggested the system of mobile application for photo-realistic VRET using smartphone, from capturing environments wherever user want to experience directly. It also contained head movement simulator for analyzing user pattern and questionnaire tool to check emotional status with questionnaires. This study hypothesized that the system can make significant emotional differences with different environments. To examine whether the system could make significant emotional difference, The experiment was designed with different environments classified with familiarity and place, based on previous studies. Participants was exposed at different and asked to complete questionnaires, which assessed arousal, valence, immersion, anxiety, and familiarity. Results showed that the system can make significant emotional difference with different environments in both familiarity and place. participants reported higher valence and lower anxiety in familiar virtual environments, and higher valence and higher immersion in outdoor virtual environments. This study discussed about the effectiveness of the system with smartphone, as one of the useful tool for photo-realistic VRET. Future study might contain a study for patients who have personal anxiety disorder.