Overcoming Phobias by Virtual Exposure

Abstract

These studies indicate VR scenes can produce a variety of phobic symptoms. While vision alone in a headset appears to create phobic anxiety, most of the researchers mentioned introduced sound into their later research and found it heightened the effect. Where applicable, haptic cues such as a hand bar in an elevator or a furry spider seems to add to the experience greatly. Although these studies provide encouragement, they raise many questions the research is just beginning to address: • How do patients treated with VR therapy compare to control groups using standard exposure therapies? • How well do any positive benefits transfer to the real world, and how long do these benefits last once the patient is no longer receiving therapy? Early research indicates the sense of fear in the virtual headset scene is measurably different from the actual experience. In a study with 40 undergraduates at two universities in Germany, Thomas Schubert and Frank Friedmann developed a questionnaire to assess feelings and experiences after headset immersion on a 15-foot diameter platform at a 25-foot height. After 20 minutes of immersion, the users answered the questionnaire assessing the fear they experienced. Their preliminary results indicate fear of height is higher if a person perceives his or her own body as a part of the VE, but that the effect varies depending on other factors. Several phobia researchers have mentioned similar anecdotal results. • Is the headset critical to the effect, or could the same results be obtained with less-expensive flat screen VR systems? James Patten at the University of Virginia has measured how HMD-based VR differs from desktop 3D graphics in inducing physiological responses. Using heart rate variability to compare arousal in the nervous system when a subject rides a virtual platform attached to the side of a building in both types of systems, they found greater sympathetic arousal in the head-tracked condition, though subjects exhibit this change to differing degrees. • What are the different effects of the lengths of exposures for the various tests? Is one, 50-minute exposure as beneficial as eight, 15-minute exposures? For safety reasons, can most patients tolerate 50 continuous minutes in a virtual scene? At least one researcher had to redesign his tests to shorten patient exposure times after several subjects became violently ill from spending an hour wearing the headset. Hopefully future phobia research will benefit from the ongoing safety research (see Viire, Stanney and Kennedy articles in this section). Despite these and other questions, phobia treatment appears to be the most easily implemented and convincing example of a beneficial use of VR therapy. When compared to training spiders and renting airplanes, the computer is more controllable and inexpensive than the conventional in vivo treatment technique. A common thread in all the present applications is the ease with which they can be implemented on present computers. Most researchers are now using PCs in their labs to create the phobia images. Several groups are developing customized low-cost systems for sale to clinicians. With these more affordable VR tools, the best measure of the effectiveness of exposure therapy may take place in doctor's offices across the country.