CBM in the Context of Exposure for Acrophobia

Study Overview
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Brief Summary
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The proposed study will apply a one-session exposure treatment combined with CBM training modifying interpretational processing biases versus a sham training in acrophobic individuals. The main aim is to advance our understanding of the mechanisms underlying exposure treatment.

Detailed Description
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The present study will apply a one-session exposure treatment followed by a computerized interpretational training (CBM) or sham training in acrophobic individuals. By doing so, it aims to better understand the mechanisms underlying exposure, i.e., the role of cognitive change. Specifically, this study aims to enhance changes in disorder-relevant cognitive processing post-exposure, compared to a sham training. Further, we hope to improve both therapy outcomes and the generalization of therapeutic effects.

Official Title
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The Effects of Exposure in the Context of Anxious Thinking Styles

Conditions
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Acrophobia

Intervention / Treatment
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* Behavioral: One session exposure treatment
* Behavioral: Sham Cognitive Bias Modification training
* Behavioral: Active Cognitive Bias Modification training


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: Informed consent Sufficient German language skills to complete the experimental tasks and questionnaires Aged between 18 and 65 years Current primary diagnosis of acrophobia as defined by DSM-5 (based on DIPS) Lives within reasonable travelling distance of the research center Exclusion criteria: Currently in psychotherapeutic treatment Impaired therapy capability (as judged by researcher/clinician) Current diagnosis of substance use disorder (via DIPS) Current or past diagnosis of psychotic disorder or bipolar disorder (via DIPS) Acute suicidality (via DIPS) Diagnosis of chronical physical or neurological diseases (self-reported by participant) Personality Disorder (via DIPS or via clinical judgement) Attention-deficit hyperactivity disorder (self-reported by participant or via DIPS) Intellectual disability (self-reported by participant or via clinical judgment) Women: pregnancy or breast feeding (self-reported by participant) Intake of medication that could impede the effects of exposure therapy or CBM training (e.g., Lorazepam)

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: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: One session exposure treatment + active Cognitive Bias Modification training<br>The exposure treatment will be administered at the tower of the German Mining museum. The day after the exposure session, patients will complete the CBM training in the lab of the Mental Health and Research Center of Ruhr University Bochum. | Behavioral: One session exposure treatment<br>* One session exposure treatment during which patients will be confronted with a height-related situation.<br>Behavioral: Active Cognitive Bias Modification training<br>* Active Cognitive Bias Modification training targeting height-related, interpretational processing biases.<br>|
| Sham Comparator: One session exposure treatment + sham Cognitive Bias Modification training<br>The exposure treatment will be administered at the tower of the German Mining museum. The day after the exposure session, patients will complete the sham CBM training in the lab of the Mental Health and Research Center of Ruhr University Bochum. | Behavioral: One session exposure treatment<br>* One session exposure treatment during which patients will be confronted with a height-related situation.<br>Behavioral: Sham Cognitive Bias Modification training<br>* Sham Cognitive Bias Modification training procedure matched in format to active training but adapted to not target height-related, interpretational processing biases.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Acrophobia-related interpretational processing biases as measured using the Encoding Recognition Task | Acrophobia-related interpretational processing biases will be measured using a modified version of the Encoding Recognition Task (ERT, Salemink & van den Hout, 2010). Bias scores of the Encoding Recognition Task can range from -4 to +4, with lower scores indicating a more negative interpretation bias. The primary outcome is change in bias score from baseline to post-training. | baseline, post-training ( 1 week post-baseline) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Acrophobia-related interpretational processing biases as measured using the Encoding Recognition Task | Acrophobia-related interpretational processing biases will be measured using a modified version of the Encoding Recognition Task (ERT, Salemink & van den Hout, 2010). Bias scores of the Encoding Recognition Task can range from -4 to +4, with lower indicating a more negative interpretation bias. | baseline, pre-training ( 1 week post-baseline), follow-up ( 5 weeks post-baseline) | 
| Heights Interpretation Questionnaire (HIQ) | The Heights Interpretation Questionnaire (HIQ; Steinman & Teachman, 2011) asks participants to rate the likelihood of eight negative interpretations for two height-related, ambiguous scenarios. Scores can range from 16 to 80, with higher scores indicating a worse outcome. | baseline, post-training ( 1 week post-baseline), follow-up ( 5 weeks post-baseline) | 
| Scrambled Sentences Task (SST) | Modified version of the Scrambled Sentences Task (Wenzlaff & Bates, 1998), including 20 height-related items that can be unscrambled into positive or negative statements. | post-training ( 1 week post-baseline), follow-up ( 5 weeks post-baseline) | 
| Danger/ Anxiety Expectancy Scale (DES/AES) | The Danger/ Anxiety Expectancy Scale (DES/AES; Gursky & Reiss, 1987) asks participants to rate the likelihood of potential harmful events passing through their mind and the likelihood to experience anxiety symptoms if confronted with heights. Scores can range from 15 to 75, with higher scores indicating a worse outcome. | baseline, post-training ( 1 week post-baseline), follow-up ( 5 weeks post-baseline) | 
| Acrophobia Questionnaire (AQ) | The Acrophobia Questionnaire (AQ; Cohen, 1977) asks participants to rate their anxiety and avoidance behavior for 20 common height-related situations. Scores can range from 0 to 160, with higher scores indicating a worse outcome. | baseline, pre-training (1 day after exposure;  1 week post-baseline), follow-up ( 5 weeks post-baseline) | 
| Behavioral Approach Task (BAT) | With the Behavioral Approach Task (BAT), participants' behavioral approach tendencies to height-relevant situations will be assessed by instructing participants to go as high as possible at the emergency staircase at the therapy center and asking participants to rate their subjective fear with the Subjective Units of Distress Scale (SUDS; Wolpe 1973). Scores can range from 0 to 100, with higher scores indicating greater fear. | baseline, post-training ( 1 week post-baseline), follow-up ( 5 weeks post-baseline) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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anxiety disorders, acrophobia, exposure, cognitive bias modification, interpretational processing biases