Extinction Generalization in Exposure Therapy

Study Overview
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Brief Summary
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Patients with anxiety disorders oftentimes express fear responses to more than only one fear-inducing object. The principal aim of this study is to examine whether the beneficial effects of exposure on fear reduction in spider phobia can extend to stimuli which are conceptually similar to spiders (i.e. cockroaches), but have never been presented during the respective treatment.

Detailed Description
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Fear extinction has evolved as the central mechanism underlying exposure-based treatments. Findings from conditioning studies indicate that fear reduction following a fear extinction procedure can generalize from the extinction stimulus to other conceptually and perceptually related stimuli. This study is aimed at translating these findings to a clinical application and will hence examine whether the basic principles of extinction generalization are applicable to exposure. Patients with spider phobia will either receive two sessions of in-vivo exposure with spiders or no treatment. Prior to as well as after treatment, patient's fear of spiders will be assessed using the Behavioral Approach Test (BATs) and self-report questionnaires. In addition, BATs with cockroaches will be conducted to examine the effects of exposure therapy on extinction generalization.

Official Title
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Extinction Generalization in Exposure Therapy for Spider Phobia

Conditions
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Specific Phobia

Intervention / Treatment
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* Behavioral: Exposure treatment for spider fear


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: spider phobia according to Diagnostic and Statistical Manual of Mental Disorders (DSM) -IV criteria Exclusion Criteria: any neurological or neuropsychiatric condition current behavioral or pharmacological treatment any mental disorder that is considered more severe than specific phobia

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Exposure Treatment<br>Participants of this arm receive two 60-minute sessions of exposure treatment for spider fear | Behavioral: Exposure treatment for spider fear<br>* Two sessions (each session = 60 minutes) of in-vivo exposure treatment (including psychoeducation) with two different spiders. Exposures comprise a hierarchy of 7 steps, to be completed with both spiders.<br>|
| No Intervention: No Exposure Treatment<br>Participants of this arm receive no exposure or other adequate treatment | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in the Behavioral Approach Test (BAT) from pre- to posttreatment | Behavioral Approach Tests with Spiders and Cockroaches will be conducted at pre- and posttreatment. Here, the closest proximity a participant is able to attain to the spider/cockroach will be measured. | Pre- and Posttreatment (with approximately 4 days between pre- and posttreatment) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Subjective Fear / Disgust during the Behavioral Approach Tests (BATs) using the Subjective Units of Distress Scale (SUDS) | Subjective Fear / Disgust during the Behavioral Approach will be assessed at the initial and final approach distances to the spider / cockroach during the respective BATs. | Pre-and Posttreatment (with approximately 4 days between pre- and posttreatment) | 
| Change in Heart Rate during the Behavioral Approach Tests (BATs) from pre- to posttreatment | During each BAT with spiders and cockroaches, heart rate will be measured. In addition, a 5-minute baseline will be recorded prior to the first BAT at each assessment. | Pre- and Posttreatment (with approximately 4 days between pre- and posttreatment) | 
| Change in the Fear of Spiders Questionnaire (FSQ) |  | Pre- and Posttreatment (with approximately 4 days between pre- and posttreatment) | 
| Change in the Spider Phobia Questionnaire (SPQ) |  | Pre- and Posttreatment (with approximately 4 days between pre- and posttreatment) | 
| Change in the Spider Beliefs Questionnaire (SBQ) |  | Pre- and Posttreatment (with approximately 4 days between pre- and posttreatment) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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exposure, spider phobia, generalization, extinction