The Link Between Mental Imagery and the Reduction of Fear in Imaginal Extinction

NCT03989518 | Completed

• 1 other identifier: 2019-00524
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

Imaginal exposure is a widely used psychological treatment technique. Imaginal extinction is an experimental analogue of imaginal exposure, that allows the study of this treatment technique under controlled circumstances (Agren, Björkstrand, \& Fredrikson, 2017). During imaginal extinction, experimentally induced fear is diminished through repeated exposure to mental imagery of the feared (conditioned) stimulus. However, it is not known to what extent fear reduction depends on the mental imagery produced during this procedure. A better understanding of the mechanisms driving the effects of imaginal exposure and the factors moderating fear reduction could have significant clinical utility, by suggesting mechanistically informed ways to improve this treatment.

Conditions

Healthy Subjects

Keywords

Imaginal extinction, imaginal exposure, mental imagery

Outcome Measures

Primary Outcomes (3)

• Skin conductance response (SCR)

  SCR is used as a measure of physiological fear responses. Differences in fear responses are used to assess fear learning during fear acquisition and to explore main effects and interactions between fear learning, stimulus complexity and capacity for mental imagery.

  Day 1

• Skin conductance response (SCR)

  SCR is used as a measure of physiological fear responses.Differences in fear responses are used to assess fear reduction during imaginal extinction, and to explore main effects and interactions between fear reduction, stimulus complexity and capacity for mental imagery.

  Day 2 (24 h after day1)

• Skin conductance response (SCR)

  SCR is used as a measure of physiological fear responses.Differences in fear response are used to assess return of fear during reinstatement, and to explore main effects and interactions between return of fear, stimulus complexity and capacity for mental imagery.

  Day 3 (48 h after day 1)

Secondary Outcomes (11)

• Fear ratings

  Day 1

• State-Trait Anxiety Inventory

  Day 1

• Difficulties in emotion regulation scale

  Day 1

• Fear ratings

  Day 2 (24 h after day 1)

• Vividness of mental imagery during imaginal extinction

  Day 2 (24 h after day 1)

Other Outcomes (3)

• Task compliance

  Day 1

• Task compliance

  Day 2 (24 h after day 1)

• Task compliance

  Day 3 (48 h after day 1)

Study Arms (2)

Simple stimuli

EXPERIMENTAL

Two perceptually simple stimuli are used during all experimental phases (geometrical figures).

Behavioral: Fear acquisition; Behavioral: Imaginal extinction; Behavioral: Reinstatement

Complex stimuli

EXPERIMENTAL

Two complex stimuli are used in all experimental phases. Stimuli consist of photographs of real objects of the same size and shape as the simple stimuli, but include perceptually more complex patterns, details and colors.

Behavioral: Fear acquisition; Behavioral: Imaginal extinction; Behavioral: Reinstatement

Interventions

Fear acquisition BEHAVIORAL

Day 1. Participants are exposed to two different visual stimuli. One of these stimuli is paired with a mild electric shock (i.e. conditioned stimuli).

Complex stimuli; Simple stimuli

Imaginal extinction BEHAVIORAL

Day 2 (24 hours after Day 1). Participants are exposed to mental imagery of the stimuli used during fear conditioning. Imagery is prompted through different verbal instructions presented in a pseudo-randomized order. No shocks are delivered. Prior to imaginal extinction, participants receive task specific training.

Complex stimuli; Simple stimuli

Reinstatement BEHAVIORAL

Day 3 (48 h after day1). Participants are exposed to the same stimuli used during fear conditioning (day 1) and imaginal extinction (day 2). Two unsignaled shocks are delivered at the beginning of the experiment, prior to the presentation of the first visual stimulus. No further shocks are delivered. This procedure allows the study of long term effects of imaginal extinction.

Complex stimuli; Simple stimuli

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18 or over
• Fluent in Swedish
• Willing and able to provide informed consent and complete study procedures

You may not qualify if:

• Current psychiatric disorder
• Use of psychotropic medication within 6 months prior to study start
• Receiving psychological treatment within 6 months prior to study start
• Current neurological condition

Sponsors & Collaborators

• Uppsala University: lead

Study Sites (1)

Uppsala University, Departement of Psychology

Uppsala, Sweden

Location

Related Publications (1)

• Agren T, Bjorkstrand J, Fredrikson M. Disruption of human fear reconsolidation using imaginal and in vivo extinction. Behav Brain Res. 2017 Feb 15;319:9-15. doi: 10.1016/j.bbr.2016.11.014. Epub 2016 Nov 10.

  PMID: 27840245 BACKGROUND

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: June 13, 2019
• First Posted: June 18, 2019
• Study Start: February 25, 2019
• Primary Completion: October 30, 2019
• Study Completion: October 30, 2019
• Last Updated: November 4, 2019

Record last verified: 2019-10

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, ICF
• Time Frame: Data will be available upon publication.

Locations

SE (1)