The Neural Mechanisms of Imaginal Extinction
- Conditions
- Fear of Spiders
- Interventions
- Behavioral: Threat conditioningBehavioral: Imaginal extinction
- Registration Number
- NCT05168592
- Lead Sponsor
- Uppsala University
- Brief Summary
Imaginal exposure is a widely used and effective psychological treatment technique in which patients are exposed to fearful stimuli and situations using mental imagery. This study examines imaginal extinction, an experimental analogue of imaginal exposure that allows the study of this treatment technique under controlled circumstances. During imaginal extinction, conditioned fear is diminished through repeated exposure to mental imagery of the feared (conditioned) stimulus. The neural underpinnings of imaginal extinction is not known, and hence, this study examines neural activations during imaginal extinction using psychophysiology and brain imaging.
- Detailed Description
In this study, participants undergo threat conditioning to two pictures (CS+, CS-) in order to acquire a conditioned threat response. After this, the conditioned threat response is diminished through imaginal extinction (i.e extinction to the mental imagery of CS+ and CS-). Functional magnetic resonance imaging (7T) is used to measure neural activations during threat conditioning and imaginal extinction. Skin conductance is used to measure arousal response. Subjective fear and mental imagery vividness ratings will also be collected. In this way, this study aims to characterize the neural underpinnings of imaginal extinction.
Note that this study employs participants fearful of spiders. This is because data collection is shared with a related study (ClinicalTrials.gov ID 2020-06930a).
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 87
- Willing and able to provide informed consent and complete study procedures
- Fear of spiders (due to data collection together with ID 2020-06930a)
- Current psychiatric disorder other than spider phobia. Current use of psychotropic medication. Current neurological conditions. MRI-contraindications (i.e metal implants in skull).
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- SINGLE_GROUP
- Arm && Interventions
Group Intervention Description Imaginal extinction Threat conditioning Conditioned fear will be diminished using imaginal extinction. Imaginal extinction Imaginal extinction Conditioned fear will be diminished using imaginal extinction.
- Primary Outcome Measures
Name Time Method Blood oxygen level dependent contrast (BOLD-signal) during threat conditioning and imaginal extinction. Day 1 BOLD-signal is assessed using functional magnetic resonance imaging.
Physiological arousal response during threat conditioning and imaginal extinction. Day 1 Skin conductance responses are used as a measure of physiological arousal response (i.e. event-related rise in electrodermal activity to stimuli).
- Secondary Outcome Measures
Name Time Method Task-specific mental imagery vividness during imaginal extinction Day 1 Vividness of Imagery (scale:1-5; no image at all - image as clear and vivid as real life)
Vividness of visual imagery Questionnaire (VVIQ) One week after Day 1 VVIQ is used to measure individual differences in the Vividness of Visual mental Imagery; scale: 16-80 where higher scores represent a higher ability for visual imagery.
Ratings of subjective fear experienced during threat conditioning and imaginal extinction. Day 1 Scale 0-100; no fear at all - extreme fear
Spielberger State-Trait Anxiety Inventory (STAI-T) One week after Day 1 STAI-T is a self-rated questionnaire included assess trait-anxiety in the participants. Scale: 20-80, where higher scores represent higher levels of trait anxiety.
Trial Locations
- Locations (1)
The Swedish 7T facility
🇸🇪Lund, Sweden