Virtual Reality Exposure Therapy for the Treatment of Social Phobia

This randomized clinical trial compares virtual reality exposure therapy to exposure group therapy to a waiting list control group.

Virtual reality exposure therapy (VRE) for the treatment of anxiety disorders has received considerable attention. During VRE, a person encounters a feared stimulus in a computer-generated environment, often through the use of a head mounted display and motion tracker that allows for multisensory input and natural movement. Several advantages of VRE have been noted - both clinical, such as treatment acceptability, and methodological, such as the ability to conduct exposure in a tightly controlled environment. Empirical support for VRE varies across anxiety disorders. Specifically, randomized controlled trials support the efficacy of VRE with fear of flying and acrophobia and show that it is equally effective as in vivo exposure. These phobias lend themselves well to VRE; the feared stimulus is circumscribed and contains powerful physical cues that can be produced within a virtual environment. There is less controlled research on the use of VRE for other anxiety disorders. The current study examines VRE for social anxiety disorder, which is characterized by fear of negative evaluation, and thus may be more difficult to evoke and treat using a virtual environment. Further, no research to date has compared VRE and the gold standard treatment for social anxiety disorder - cognitive behavioral therapy in a group format.

The purpose of the current study is to compare VRE and Exposure Group Therapy to wait list in a sample of adults meeting criteria for social anxiety disorder with a primary fear of public speaking. It is hypothesized that, relative to wait list, those receiving treatment will improve on standardized measures of public speaking fears and fears of negative evaluation, as well as a behavioral avoidance task. Participants also are expected to maintain treatment gains at 3 and 12-month follow-up. Comparisons between the two active treatments also will be made.

Procedure

Following consent, study candidates completed a phone interview to screen for obvious exclusion criteria (e.g., current treatment for social anxiety disorder) and then an in-person, pretreatment assessment consisting of the Structured Clinical Interview for the DSM-IV (SCID), speech task, and the battery of self-report measures. Eligible participants were randomly assigned to virtual reality exposure therapy, exposure group therapy, or wait list by simple randomization using a computerized random number generator. Concealment procedures were used to prevent foreknowledge of treatment assignment from influencing enrollment. Each potential participant had a participant number, which was only known by the study coordinator. The first author kept a hard copy of a list linking participant number to condition assignment in a locked file drawer. Once a participant was enrolled, the study coordinator asked for the treatment condition for a particular participant number. The first author had no knowledge of which participant was linked with a participant number, and the study coordinator had no knowledge of which participant number was linked with treatment condition. Participants assigned to wait list were re-randomized to virtual reality exposure therapy or exposure group therapy following the waiting period (Figure 1). Participants completed all assessment and treatment sessions at a psychology clinic within at an urban research university that is accessible by public transportation.

Assessments

Participants completed assessments at pretreatment, posttreatment, and follow-up. Self-report outcome measures were completed at each assessment point. Participants were asked to complete the behavioral avoidance task at pretreatment and posttreatment. The anxiety, mood, and substance use modules of the SCID were administered at pretreatment, and the anxiety module was administered at the 3-month follow-up.

All assessments were conducted by doctoral students who were blind to the type of treatment to be received. All pretreatment and follow-up diagnostic assessments were videotaped, and a randomly selected subset (N=10) were reviewed by a licensed psychologist to calculate the inter-rater reliability of pretreatment assessment (100% agreement for primary diagnosis, with one disagreement on severity). Compensation was provided to participants who completed the self-report battery of measures administered at posttreatment, 3- and 12-month follow-up.

Treatment

Prior to administering therapy, study therapists attended two day training workshops for each treatment, led by the developers of the respective treatments. Each study therapist also received weekly supervision by the first author. There were 5 study therapists: 2 licensed clinical psychologists with experience in manualized treatment, and 3 doctoral students with no experience with manualized treatments. All therapists administered both treatments.

Both treatments were administered according to a manualized protocol for 8 sessions. The VRE and EGT treatment groups were designed to be as similar as possible, with the exception of the modality for the delivery of exposure. Both treatments began with a treatment rationale and psychoeducation about social anxiety disorder. During sessions 2- 8, both treatments addressed specific aspects of social anxiety disorder identified in psychopathology literature, including self-focused attention, perceptions of self and others, perceptions of emotional control, rumination, realistic goal setting for social situations through the use of such techniques as cognitive preparation, and challenging of cost and probability biases. Session 8 also included relapse prevention. Homework was assigned for both treatments, including a daily mirror task, daily record of social situations, and identification of cognitive biases.

Virtual Reality Exposure (VRE)

Virtual environments included a virtual conference room (\~5 audience members), a virtual classroom (\~35 audience members), and a virtual auditorium (100+ audience members). Therapists could manipulate audience reactions in a number of ways including making them appear interested, bored, supportive, hostile, distracted (i.e., cell phone ringing). Virtual audience members could also pose questions, either standardized (e.g., "I don't understand, could you explain again") or tailored to the client using therapist voice-over. Virtual environments were manipulated according to the participants fear hierarchy. Participants were exposed to each item on their hierarchy until their fear decreased.

Exposure Group Therapy (EGT)

EGT was co-led by a licensed clinical psychologist and an advanced doctoral student. Groups consisted of up to five participants. During exposure, participants gave a videotaped speech in front of the group. Group members were also asked to provide each other with positive feedback when the videotaped speeches were reviewed.

Every effort was made to equate time in exposure across treatment group. Participants receiving VRE completed 4 trials of exposure. Because of the risk of simulator sickness (e.g., headaches, nausea), exposure trials lasted no longer than 30 minutes, for a total of up to 120 minutes. Participants receiving EGT received 6 trials of exposure. The amount of time spent on each group member varied according to the number of participants in the group. On average, for a group with 4 participants, participants completed 6 trials of exposure for 20 minutes for a total of 120 minutes.

Wait List

After 8 weeks, wait list participants completed the self-report battery. Wait list participants were re-randomized to either virtual reality exposure or exposure group therapy following the waiting period and received the same 8-week treatment protocol described above.

Eligibility Criteria:
Inclusion Criteria:

* Speakers of English meeting DSM-IV (APA, 2000) criteria for a primary diagnosis of social anxiety disorder
* Self-identifying public speaking as their primary social fear
* Participants were required to be stabilized on psychoactive medication(s) and dosage(s) for 3 months.

Exclusion Criteria:

* history of mania, schizophrenia, or psychosis
* current suicidal ideation, alcohol, or substance dependence
* inability to tolerate the virtual reality helmet/environment
* history of seizures
* concurrent psychotherapy for social anxiety disorder