Neural Mechanisms of Imaginal and in Vivo Exposure

NCT05193383 | Completed

• 1 other identifier: 2020-06930a
• Study Type: interventional
• Target: 87
• Locations: 1 country
• Sites: 1

Brief Summary

Imaginal exposure is a widely used and effective psychological treatment technique. Recent research suggests that neural activations and emotional responses during imaginal exposure are similar to those elicited during in vivo exposure. However, to the investigators knowledge, no direct comparison between in vivo and imaginal exposure has been performed during neuroimaging. This study compares neural activations and emotional responses during imaginal and in vivo exposure. This study also explores the generalizability of fear reduction achieved through imaginal exposure to fear responses elicited by in vivo stimuli, and vice versa, in a follow-up session approximately one week later. A better understanding of the mechanisms behind both types of exposure could have significant clinical utility, as well as elucidate the differences between fear created from outward stimuli and fear created from inward stimuli, such as mental imagery.

Conditions

Fear of Spiders

Keywords

Imaginal exposure; Exposure; Mental Imagery

Outcome Measures

Primary Outcomes (5)

• Blood oxygen level dependent contrast (BOLD-signal) during exposure to fearful stimuli (in vivo or imaginal).

  BOLD-signal is assessed using functional magnetic resonance imaging.

  Day 1

• Physiological arousal response during exposure (in vivo or imaginal).

  Skin-conductance responses are used as a measure of physiological arousal response, i.e. event-related rise in electrodermal activity as a response to stimulus. Unit of measure is microSiemens.

  Day 1

• Physiological arousal response during follow-up exposure

  Skin-conductance responses are used as a measure of physiological arousal response, i.e. event-related rise in electrodermal activity as a response to stimulus. Unit of measure is microSiemens.

  One week after Day 1

• Ratings of subjective fear experienced during exposure to fearful stimuli and neutral stimuli

  Scale 0-100; no fear at all - extreme fear

  Day1

• Ratings of subjective fear experienced during exposure to fearful stimuli and neutral stimuli

  Scale 0-100; no fear at all - extreme fear

  One week after Day 1

Secondary Outcomes (6)

• Ratings of subjective fear participants expect to experience during exposure to fearful stimuli

  Day 1 & one week after Day 1

• Number of approach-avoidance decisions during an approach-avoidance behaviour task using fearful stimuli (spiders)

  One week after Day 1

• Task-specific mental imagery vividness ratings to fearful and neutral stimuli during imaginal exposure, and follow-up exposure (not applicable during in vivo exposure).

  Day 1 & one week after Day 1

• Spielberger State-Trait Anxiety Inventory (STAI-T)

  One week after Day 1

• Vividness of visual imagery Questionnaire (VVIQ)

  One week after Day 1

Study Arms (2)

Imaginal exposure

EXPERIMENTAL

Exposure to mental imagery including a fearful stimulus (spider) and corresponding scenes including a neutral stimulus (leaf)

Behavioral: Imaginal exposure; Behavioral: Exposure; Behavioral: Approach-avoidance conflict

In vivo exposure

EXPERIMENTAL

Exposure to video clips including a fearful stimulus (spider) and corresponding clips including a neutral stimulus (leaf)

Behavioral: Exposure; Behavioral: Approach-avoidance conflict; Behavioral: In vivo exposure

Interventions

Imaginal exposure BEHAVIORAL

Session 1 (Day 1): Participants receive repeated exposure to mental imagery of fear-provoking stimuli (spiders) and neutral stimuli (leaves) while undergoing brain imaging med fMRI.

Imaginal exposure

Exposure BEHAVIORAL

Session 2 (Ca one week): Participants receive both imaginal and in vivo exposure to fear-provoking stimuli and neutral stimuli (both arms are exposed to both video clips (in vivo exposure) and mental imagery (imaginal exposure). Session 2 is conducted in the laboratory, i.e., no brain imaging.

Imaginal exposure; In vivo exposure

Approach-avoidance conflict BEHAVIORAL

Session 2 (Ca one week): Spider fear is probed by an approach-avoidance conflict task. Participants can receive varying small rewards for watching pictures of spiders, or avoid the spider pictures at the cost of not receiving a reward (neutral pictures are shown instead).

Imaginal exposure; In vivo exposure

In vivo exposure BEHAVIORAL

Session 1 (Day 1): in vivo exposure. Participants receive repeated exposure to film clips of fear-provoking stimuli (spiders) and neutral stimuli (leaves) while undergoing brain imaging med fMRI.

In vivo exposure

Eligibility Criteria

• Age: 18 Years - 60 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Willing and able to provide informed consent and complete study procedures
• Fear of spiders

You may not qualify if:

• Current psychiatric disorder other than spider phobia
• Current use of psychotropic medication
• Current neurological conditions
• MRI-contraindications (i.e metal implants in skull)

Sponsors & Collaborators

• Uppsala University: lead

Study Sites (1)

The Swedish 7T facility

Lund, 22242, Sweden

Location

Related Publications (1)

• Hoppe JM, Holmes EA, Agren T. Exploring the neural basis of fear produced by mental imagery: imaginal exposure in individuals fearful of spiders. Philos Trans R Soc Lond B Biol Sci. 2021 Feb;376(1817):20190690. doi: 10.1098/rstb.2019.0690. Epub 2020 Dec 14.

  PMID: 33308073 RESULT

MeSH Terms

Conditions

Arachnophobia

Interventions

Implosive Therapy

Intervention Hierarchy (Ancestors)

Desensitization, Psychologic; Behavior Therapy; Psychotherapy; Behavioral Disciplines and Activities

Study Officials

• Thomas Ågren, PhD

  Uppsala University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 9, 2021
• First Posted: January 14, 2022
• Study Start: April 7, 2022
• Primary Completion: March 1, 2023
• Study Completion: March 1, 2023
• Last Updated: August 26, 2024

Record last verified: 2024-08

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF
• Time Frame: Data will be available from completion of analysis and publication, and onwards.
• Access Criteria: Anonymous behavioural and brain imaging data, training material, Statistical Analysis plan, and informed consent form will be made public on the project site on Open Science Framework (https://osf.io/vmrpw/).

Locations

SE (1)