Neural Activations During Imaginal Exposure in Individuals Fearful of Spiders

Study Overview
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Brief Summary
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This study explores the brain basis of imaginal exposure, a widely used psychological treatment technique. Specifically, this study uses functional magnetic resonance imaging to examine brain areas activated during imaginal exposure, in individuals fearful of spiders. Physiological responses and subjective fear experienced during imaginal exposure are also assessed. The primary aim of this study is to explore differences in neural activity during exposure to phobic, compared to neutral, mental imagery. The study will focus primarily on exploratory whole brain analyses, but will also include regions of interest analyses on brain areas previously associated with imaginal exposure. The experimental procedure consists of repeated exposure to mental imagery, i.e. imagery of short durations, including either highly emotion-provoking or neutral content, prompted by verbal instructions. A secondary aim is to explore the effects of repeated exposure to mental imagery, used during the experimental procedure, on subjective fear and physiological responses.

Detailed Description
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Results will elucidate if neural activity to phobic imagery differs from activity associated with the production of mental imagery per se. Findings will also increase our general understanding of the neural basis of imaginal exposure treatments.

Official Title
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Neural Activations During Imaginal Exposure in Individuals Fearful of Spiders

Conditions
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Individuals With Fear of Spiders

Intervention / Treatment
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* Behavioral: Imaginal exposure


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Significant fear of spiders Exclusion Criteria: Current psychiatric disorder other than spider phobia Substance abuse Neurological disease Psychological treatment or psychotropic medication within six months Magnetic resonance imaging contradiction

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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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Imaginal exposure<br>The experimental procedure consists of imaginal exposure to mental imagery of phobic and neutral stimuli, prompted through recorded verbal instructions. Participants' repeat the experimental procedure one week later in a follow-up session. Brain imaging data is only collected during day 1 | Behavioral: Imaginal exposure<br>* Imaginal exposure to mental imagery of phobic and neutral stimuli<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Blood oxygen level dependent contrast (BOLD-signal) | BOLD-signal is assessed using functional magnetic resonance imaging. | Day 1 | 
| Physiological response during exposure to mental imagery | Skin-conductance responses are used as a measure of physiological response. | Day 1 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Physiological response during exposure to mental imagery | Skin-conductance responses are used as a measure of physiological response. | Follow-up (one week after day 1) | 
| Differences in physiological response during exposure to mental imagery, during day 1 compared to the follow-up session. | Skin-conductance responses are used as a measure of physiological response. | Difference between day 1 and the follow-up session (one week after day 1) | 
| Ratings of subjective fear participants' expect to experience during exposure to mental imagery | Scale: 0-100; no fear at all - extreme fear. | Day 1 | 
| Ratings of subjective fear experienced during exposure to mental imagery | Scale: 0-100; no fear at all - extreme fear. Fear ratings are completed immediately after the imaginal exposure experimental procedure | Day 1 | 
| Spielberger State-Trait Anxiety Inventory (STAI-S) | STAI-S is a self-rated questionnaire included to assess state-anxiety experienced during exposure. High scores indicate high levels of state anxiety (range, total score: 20 - 80). | Day 1 | 
| Differences in ratings of subjective fear during exposure to mental imagery, during day 1 compared to the follow-up session. | Scale: 0-100; no fear at all - extreme fear. | Difference between day 1 and the follow-up session (one week after day 1) | 
| Vividness of mental imagery | Vividness of mental imagery of phobic stimuli (scale: 1-5; no image at all - image as clear and vivid as real life). | Day 1 | 
| Vividness of mental imagery | Vividness of imagery of phobic stimuli (scale: 1-5; no image at all - image as clear and vivid as real life). | Follow-up (one week after day 1) | 
| Differences in vividness of mental imagery, during day 1 compared to the follow-up session. | Vividness of imagery of phobic stimuli (scale: 1-5; no image at all - image as clear and vivid as real life). | Difference between day 1 and the follow-up session (one week after day 1) | 
| Difficulties in emotion regulation scale (DERS) | DERS is a self-rated questionnaire, included to explore potential relations between imaginal exposure and difficulties in emotion regulation. High scores indicate more difficulties in emotion regulation (range, total score: 36 - 180) | Day 1 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Imaginal exposure, brain imaging, mental imagery