Fear of Spiders
Conditions
Keywords
Threat conditioning, Extinction, Imaginal Extinction, Mental Imagery
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).
Interventions
BEHAVIORALThreat conditioning
Day 1: The participant is repeatedly shown two stimulus (CS+,CS-), one at a time. CS+ is paired with an electric shock. CS- acts as a control stimulus. The stimuli consist of photos of two different objects. Stimuli will be counterbalanced between participants.
BEHAVIORALImaginal extinction
Day 1: Participants are repeatedly instructed to produce mental imagery of the two stimuli used during threat conditioning. Imagery is prompted through different written instructions presented in pseudo-randomized order on a screen. No shocks will be delivered.
Sponsors
Uppsala University
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
* Willing and able to provide informed consent and complete study procedures * Fear of spiders (due to data collection together with ID 2020-06930a)
Exclusion criteria
* Current psychiatric disorder other than spider phobia. Current use of psychotropic medication. Current neurological conditions. MRI-contraindications (i.e metal implants in skull).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 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
| Measure | Time frame | Description |
|---|---|---|
| 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) |
| 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. |
| 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. |
Countries
Sweden
Outcome results
None listed