EMDR in Spider Phobia: Work Mechanisms and Treatment Outcome

Study Overview
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Brief Summary
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The goal of this study is to increase the efficiency of exposure in virtual reality (VR). Based on the EMDR research the investigators would like to show that the implementation of eye movements during the VR exposure results in a faster physiological relaxation response among probands with spider phobia, which has a positive effect on the subjective and behavioral efficacy of the VR exposure.

Detailed Description
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The VR paradigm consists of one room with a spider in it. The proband is supposed to look at it for a few minutes. This exposure is repeated several times. In the experimental group a ball appears during the exposure, that moves horizontally across the room. The probands are supposed to follow this movement with their eyes. EDA, EKG and respiration are being recorded. Furthermore the subjective and behavioral spider phobia is measured before, during and after the exposure to determine occurring changes.

Official Title
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EMDR in Spider Phobia: Work Mechanisms and Treatment Outcome

Conditions
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Spider Phobia

Intervention / Treatment
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* Behavioral: Eye Movement Desensitization and Reprocessing Therapy
* Behavioral: Virtual Reality Exposure Therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: the Structured Clinical Interview for DSM-IV (SCID, First et al., 2002; applied German translation: Strukturiertes Klinisches Interview für DSM-IV, Achse I, SKID I, Wittchen et al., 1997), in order to get a reliable diagnosis of spider phobia Exclusion Criteria: pregnancy current psychopharmacological medication current involvement in psychiatric- or psychotherapeutic treatment cardiovascular or neurological diseases color blindness hearing disorders

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 55 Years

Sexes Eligible for Study
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Female

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: Eye movements<br>Eye Movement Desensitization and Reprocessing Therapy + virtual reality exposure therapy | Behavioral: Eye Movement Desensitization and Reprocessing Therapy<br>* In 1989, Shapiro discovered that while talking about negative life events or thoughts, rhythmic eye movements on a horizontal axis can alleviate the associated vividness and burden (Shapiro, 1989). She established the psychodynamic-behavioral Eye Movement Desensitization and Reprocessing (EMDR) Therapy, which includes the induction of rhythmic eye movements as a central feature. EMDR is regarded as an efficient treatment tool. Several times it has also been successfully applied in the field of specific phobias (de Jongh, ten Broeke, & Renssen, 1999; de Jongh, Holmshaw, Carswell, & van Wijk, 2011; Lapsekili & Yelboga, 2014; Muris, Merckelbach, van Haaften, & Mayer, 1997) and there is a standard protocol for using EMDR on specific fears and phobias (de Jongh, 2015).<br>Behavioral: Virtual Reality Exposure Therapy<br>* Exposure to fear-evoking stimuli is conducted more often in virtual environments using simulators or similar computer-technologies (Virtual Reality Exposure Therapy, VRET). One great advantage of using VR-technologies is that it is possible to create an environment which is highly controllable by its creators. Feared stimuli or scenarios can be varied on individual purposes and presented several times. This facili- tates the practice of exposure-based treatments especially for situations or places diffi- cult to access or requiring a considerable amount of time and/or money (e.g. being in war zones or a passenger on a flight), where in vivo exposures have often not been con- ducted or only in a limited manner (Mühlberger & Pauli, 2011).<br>|
| Active Comparator: Control<br>virtual reality exposure therapy | Behavioral: Virtual Reality Exposure Therapy<br>* Exposure to fear-evoking stimuli is conducted more often in virtual environments using simulators or similar computer-technologies (Virtual Reality Exposure Therapy, VRET). One great advantage of using VR-technologies is that it is possible to create an environment which is highly controllable by its creators. Feared stimuli or scenarios can be varied on individual purposes and presented several times. This facili- tates the practice of exposure-based treatments especially for situations or places diffi- cult to access or requiring a considerable amount of time and/or money (e.g. being in war zones or a passenger on a flight), where in vivo exposures have often not been con- ducted or only in a limited manner (Mühlberger & Pauli, 2011).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Behavioral Assessment Test (BAT) in vivo | expected fear just before getting started and actually present fear just before finishing | 5 minutes before, 5 minutes after intervention and during folow up (2 weeks post Intervention) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Skin Conductance Reactivity (SCR) |  | during the VR-session | 
| Electrocardiogram (ECG) | providing the Heart Rate (HR) | during the VR-session | 
| manipulation check electrode below the right eye (M. orbicularis oculi) | for registering eye movements | during the VR- exposure sessions (5 min x 4 sessions) | 
| Change in Subjective Fear Ratings | Subjective Units of Disturbance Scale | 1 min before and during ( each minute) exposure in Virtual Reality |