206 IEEE TRANSACTIONS ON INFORMATION TECHNOLOGY IN BIOMEDICINE, VOL. 6, NO. 3, SEPTEMBER 2002 Virtual Reality Treatment of Flying Phobia Rosa M. Baños, Cristina Botella, Concepción Perpiñá, Mariano Alcañiz, Jose Antonio Lozano, Jorge Osma, and Myriam Gallardo Abstract—Flying phobia (FP) might become a very incapac- itating and disturbing problem in a person’s social, working, and private areas. Psychological interventions based on exposure therapy have proved to be effective, but given the particular nature of this disorder they bear important limitations. Exposure therapy for FP might be excessively costly in terms of time, money, and efforts. Virtual reality (VR) overcomes these difficulties as different significant environments might be created, where the patient can interact with what he or she fears while in a totally safe and protected environment—the therapist’s consulting room. This paper intends, on one hand, to show the different scenarios designed by our team for the VR treatment of FP, and on the other, to present the first results supporting the effectiveness of this new tool for the treatment of FP in a multiple baseline study. Index Terms—Anxiety disorders, flying phobia (FP), virtual ex- posure, virtual reality (VR). I. INTRODUCTION F LYING phobia (FP) is an important problem affecting a great percentage of the general population. Approximately 25% of adult people experience a significant anxiety level when required to fly; from those, 10% avoid such a situation [1]. How- ever, these data contrast with the evidence shown by the statis- tics on airplane safety. According to the U.S. Department Trans- portation Document report of 1985 [1], air transportation is safer that any other such as car, boat, bus, etc. Despite all these data, the number of persons suffering from FP is much greater than the corresponding figure of persons suffering from phobias to other much more insecure transportation means [1]. According to DSM-IV [2] this problem would be diagnosed as a specific situational phobia, since what characterizes FP is an intense fear experienced in situations related to flying by plane. It is important to consider that the feared situations may not only include flying, but also taking somebody to the airport, for in- stance. Anticipatory anxiety may also appear, e.g., when buying the plane ticket, confirming the flight, waiting at the boarding area, or even at home while packing for the trip. Such a fear makes the person try to avoid airplane related situations or, in case he/she does not avoid, endure them with great distress. The person may face those situations but experience a considerable amount of anxiety and perform some kind of safety behaviors Manuscript received December 18, 2000; revised April 15, 2002. This work was supported in part by the I+D FEDER Program under Grant 1FD97-0260-C02-01. R. M. Baños and C. Perpiñá are with the Departamento de Personalidad, Eval- uacion y Tratamientos Psicologicos, Universidad de Valencia, Valencia 46040, Spain. C. Botella, J. Osma, and M. Gallardo are with the Departamento de Psicologia Basica, Clinica y Psicobiologia, Universidad Jaume I, Castellón, Spain. M. Alcañiz and J. A. Lozano are with the MedicLaboratory, Universidad Po- litecnica de Valencia, Valencia 46040, Spain. Publisher Item Identifier 10.1109/TITB.2002.802380. such as taking tranquilizers or alcohol, choosing the seats next to the emergency exits or the aisle, not looking through the win- dows, etc. Despite that from this perspective FP seems to appear as an easy issue in terms of assessment and diagnosis, the truth is that we are dealing with a heterogeneous problem. The fears reported by the persons with FP are many and of diverse nature. Flying phobics may be afraid of having an airplane crash, of the physical sensations of anxiety they might experience, of heights, of moving away from a safe place such as home, of being closed, of “loosing control” or not having control over the situation, etc. That is, fear of flying appears not to be a unitary phenomenon [3], [4]. It can be a situational phobia or the expression of other phobias (such as claustrophobia, acrophobia, or agoraphobia) or even of panic disorder. Thus, it is of basic importance to ex- amine all these conditions because in the case FP is just a sign of a problem of greater magnitude, treatment should be aimed to the main disorder. Despite the high prevalence of this problem, well-designed and controlled treatment outcome studies are scarce [3], [5]–[9]. Actually, many authors have raised their complaints about the neglect suffered by this type of phobia [4]. One of the possible explanations to this fact may lie in the difficulty and high cost that any research or treatment would imply. The psychological treatment that has proven to be the most effective in the treat- ment of phobias is in vivo exposure. However, the resources and time necessary to carry out this type of exposure have daunted many researchers, therapists, and patients. The group of Rothbaum and Hodges was one of the pioneers in considering fear of flying as an ideal candidate for virtual reality (VR) exposure therapy [10]. They accounted for a series of reasons, to which we add some more. First, VR has demonstrated to be a useful tool for activating several fears, and some of them are of relevance for FP, such as acrophobia [11], [12] and claustrophobia [13]. Those fears were capable of being activated by means of VR and consequently they were extin- guished by repeated and controlled virtual exposure. Second, as mentioned above, in vivo exposure for FP is expensive and, furthermore, difficult to plan, as all the variables needed to manage a well-graded exposure cannot be controlled. That is why the alternative choice for treatment was imagination exposure. Compared with the latter, VR exposure creates a greater sense of presence and is much more immersive. This is a core issue since therapy is aimed at facilitating emotional pro- cessing, which requires activation of the fear structures in order for them to be modified [14], [15]. Third, it is not too difficult to design scenarios including the basic aspects of fear of flying and improving reality judgment by means of instigators such as real airplane seats or sound effects of real planes. Fourth, we believe that it is absolutely justified to invest resources in 1089-7771/02$17.00 © 2002 IEEE