Augmenting Virtual Reality Exposure Therapy for Acrophobia

Study Overview
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Brief Summary
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This study will examine whether tactile feedback and point-based rewards can be used to improve outcomes from virtual reality exposure therapy for acrophobia.

Detailed Description
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Exposure therapy is one of the most potent techniques available for treating anxiety-related disorders, including specific phobia. However, estimates suggest that 10-48% of anxiety patients do not fully respond to exposure therapy. Meta-analyses demonstrate that virtual reality exposure therapy (VRET) is equally effective as traditional, in vivo ('in life') exposure therapy. Furthermore, individuals with anxiety disorders report greater preference (and lower likelihood of treatment refusal) for VR, rather than in vivo, exposure therapy. Although VRET has well-established efficacy and is rapidly growing in popularity, there has been very little research evaluating how specific elements of VR game design might be used to improve outcomes from VRET. This study evaluates two game design elements that we hypothesize will improve VRET outcomes: tactile feedback and a point-based reward system. Tactile feedback (TF; i.e., touching a real object that matches an element in the VR environment) enhances sense of presence in VR. Higher presence activates anxiety during VRET, which is essential for promoting the active mechanisms of exposure therapy and may also improve treatment retention. On the other hand, point-based rewards (PR) in games enhance sense of competence (i.e., sense of progress and achievement), and increase both enjoyment and likelihood of future use of games. Furthermore, several studies demonstrate that PR improves traditionally difficult-to-change health behaviors, such as increasing exercise frequency and reducing misuse of pain medications. Although this research is promising, the impact of PR on VRET is unknown. To test the influence of TF and PR on VRET outcomes, we will randomize participants with acrophobia to receive (a) standard virtual reality exposure therapy, (b) VRET with tactile feedback, (c) VRET with a point-based reward system, or (d) VRET with tactile feedback and a point-based reward system. Participants' fear reactivity will be assessed with behavioral, physiological, and subjective/self-report measures at baseline, post-treatment, and follow-up.

Official Title
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Augmenting Virtual Reality Exposure Therapy for Acrophobia With Tactile Feedback and Point-based Rewards

Conditions
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Specific Phobia, Anxiety Disorders, Fear of Heights, Acrophobia

Intervention / Treatment
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* Behavioral: Virtual Reality Exposure Therapy
* Behavioral: Tactile Feedback
* Behavioral: Point-based Rewards


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Fluent in English Indicates sufficient fear of heights based on responses (a) on a self-report questionnaire (the Acrophobia Questionnaire) administered at prescreening, and (b) on Behavioral Avoidance Tests administered at baseline. Exclusion Criteria: Already receiving exposure therapy for height phobia

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Participants will be randomly assigned to receive virtual reality exposure therapy with tactile feedback, point-based rewards, both tactile feedback and point-based rewards, or neither tactile feedback nor point-based rewards.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Exposure with Tactile Feedback<br>Participant completes virtual reality exposure therapy for acrophobia involving walking across a plank at higher and higher levels in a virtual city environment. In the real world, the participant walks across an actual wooden plank on the floor, which mirrors the plank in the virtual world. | Behavioral: Virtual Reality Exposure Therapy<br>* Participant completes virtual reality exposure therapy for acrophobia involving walking across a plank at higher and higher levels in a virtual city environment.<br>Behavioral: Tactile Feedback<br>* In the real world, the participant walks across an actual wooden plank on the floor, which mirrors the plank in the virtual world.<br>|
| Experimental: Exposure with Point-based Rewards<br>Participant completes virtual reality exposure therapy for acrophobia involving walking across a plank at higher and higher levels in a virtual city environment. The participant has the opportunity to pop balloons upon reaching the ends of the plank to gain points. Participant's popping instrument in the virtual world upgrades as more points are accumulated. | Behavioral: Virtual Reality Exposure Therapy<br>* Participant completes virtual reality exposure therapy for acrophobia involving walking across a plank at higher and higher levels in a virtual city environment.<br>Behavioral: Point-based Rewards<br>* Participant has the opportunity to pop balloons upon reaching the ends of the plank to gain points. Participant's popping instrument in the virtual world upgrades as more points are accumulated.<br>|
| Experimental: Exposure with Tactile Feedback and Point-based Rewards<br>Participant completes virtual reality exposure therapy for acrophobia involving walking across a plank at higher and higher levels in a virtual city environment. In the real world, the participant walks across an actual wooden plank on the floor, which mirrors the plank in the virtual world. Also, the participant has the opportunity to pop balloons upon reaching the ends of the plank to gain points. Participant's popping instrument in the virtual world upgrades as more points are accumulated. | Behavioral: Virtual Reality Exposure Therapy<br>* Participant completes virtual reality exposure therapy for acrophobia involving walking across a plank at higher and higher levels in a virtual city environment.<br>Behavioral: Tactile Feedback<br>* In the real world, the participant walks across an actual wooden plank on the floor, which mirrors the plank in the virtual world.<br>Behavioral: Point-based Rewards<br>* Participant has the opportunity to pop balloons upon reaching the ends of the plank to gain points. Participant's popping instrument in the virtual world upgrades as more points are accumulated.<br>|
| Other: Virtual Reality Exposure Therapy Alone<br>Participant completes virtual reality exposure therapy for acrophobia involving walking across a plank at higher and higher levels in a virtual city environment. | Behavioral: Virtual Reality Exposure Therapy<br>* Participant completes virtual reality exposure therapy for acrophobia involving walking across a plank at higher and higher levels in a virtual city environment.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Behavioral approach test (BAT)- generalization context | Participants will walk up a staircase until they reach the highest level they can complete. During each BAT, we will assess fear response behaviorally (highest step reached up to 101 steps), physiologically (heart rate and electrodermal activity), and subjectively (self reported levels of anticipated and peak fear). | Change from baseline to one-month follow-up | 
| Behavioral approach test (BAT) -treatment context | Participants will stand on a plank in virtual reality and raise the plank until they reach the highest level they can complete. During each BAT, we will assess fear response behaviorally (highest step reached up to 70 steps), physiologically (heart rate and electrodermal activity), and subjectively (self reported levels of anticipated and peak fear). | Change from baseline to one-month follow-up | 
| Acrophobia Questionnaire (AQ) | Participants will complete the AQ, a 40-item questionnaire that assesses self-reported anxiety and avoidance related to acrophobia. Scores for each subscale are summed, and totals range from 0 to 120 for each subscale, with higher scores indicating greater anxiety or avoidance. | Change from baseline to one-month follow-up | 
| Heights Interpretation Questionnaire (HIQ) | Participants will complete the HIQ, a 16-item questionnaire that assesses self-reported interpretations of an imagined experience of heights. Items are summed scored, and totals ranged from 16 to 80, with higher scores indicating greater height fear-relevant interpretation bias. | Change from baseline to one-month follow-up | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Anxiety Disorders Interview Schedule for the Diagnostic and Statistical Manual of Mental Disorders (DSM)-5 - Specific Phobia Module | Participants will be given a structured interview to determine whether they meet diagnostic criteria for specific phobia. | Change from baseline to one-month follow-up | 
| Treatment Drop-out Questionnaire | Experimenters will record whether or not participants drop out of treatment. This will be operationalized as beginning virtual reality exposure therapy, but discontinuing the study before the two-session treatment is complete. | Post-treatment (about 1 week) | 
| Willingness to continue exposure therapy | This scale will assess assess whether participants would be willing (from 0% to 100%) to use the heights exposure program at home, or to return to the lab for another therapy session. | Post-treatment (about 1 week) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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exposure therapy, virtual reality, acrophobia, fear of heights