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Neuroimaging of Pavlovian Fear Conditioning Processes in Patients With Pathological Anxiety

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. Identifier: NCT03498599
Recruitment Status : Recruiting
First Posted : April 13, 2018
Last Update Posted : April 13, 2018
Information provided by (Responsible Party):
University of Texas at Austin

Brief Summary:

The purpose of this study is to use functional magnetic resonance imaging to investigate how the human brain learns to form associations between neutral and emotional stimuli. The study is based on the basic principles of Pavlovian conditioning.

When someone learns that a neutral stimulus (such as the sound of a bell) predicts an unpleasant stimulus (such as a mild electrical shock), the neutral stimulus takes on the properties of an emotional stimulus.

The investigators are interested in the neural processes involved in this learning in people with a clinical anxiety disorder and posttraumatic stress disorder (PTSD).

Condition or disease Intervention/treatment Phase
Post Traumatic Stress Disorder Anxiety Disorders Panic Disorder Social Phobia Phobia Behavioral: Novelty facilitated extinction Behavioral: Standard Extinction Not Applicable

Detailed Description:

This study uses functional MRI in people with anxiety and stress-related disorders to evaluate the neural correlates of fear conditioning and extinction. During fear conditioning participants see a picture of a face that predicts a mild electrical shock to the wrist. Participants then return the next day to the scanner for a test of fear expression 24-hours after fear conditioning. The investigators are simultaneously measuring autonomic arousal in the scanner using measures of skin conductance responses (i.e., sweating).

The primary objective of this study is to evaluate different forms of Pavlovian fear extinction in patients who suffer from pathological anxiety. The investigators are interested in the effects of extinction and extinction retention over a delay in regions that are known to show abnormalities in anxiety populations. This includes the amygdala, ventromedial prefrontal cortex, and the hippocampus.

The study is testing behavioral strategies and does not include any pharmacological manipulations.

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 40 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Participant)
Primary Purpose: Basic Science
Official Title: Improving the Control of Fear: Healthy Adults to Pathological Anxiety
Actual Study Start Date : August 1, 2017
Estimated Primary Completion Date : June 2020
Estimated Study Completion Date : June 2020

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Anxiety

Arm Intervention/treatment
Experimental: Novelty facilitated extinction
Behavioral intervention. After Pavlovian fear conditioning, the shock is omitted and replaced by a novel, surprising, and neutral auditory tone.
Behavioral: Novelty facilitated extinction
In the novelty-facilitated extinction design, the aversive outcome (i.e., mild unpleasant electrical pulse) is omitted and replaced by a low volume auditory tone.

Standard extinction
The shock is omitted during standard extinction
Behavioral: Standard Extinction
During standard fear extinction the expected aversive outcome is omitted.

Primary Outcome Measures :
  1. Changes in functional magnetic resonance imaging (fMRI)-BOLD (blood-oxygen-level dependent) signal in sensory, prefrontal, and limbic regions during a study on the neurobiology of Pavlovian fear conditioning in humans [ Time Frame: Only on the day of the experiment ]
    We are measuring increases in the BOLD signal in response to visual stimuli during a Pavlovian conditioning task in humans.

Secondary Outcome Measures :
  1. Skin conductance responses evoked during a Pavlovian fear conditioning task in humans as an index of physiological arousal. [ Time Frame: Only on the day of the experiment ]
    Electrodermal activity collected from the hand that measures increases in sweating, taken as an indicator of Pavlovian fear conditioning

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   18 Years to 50 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  1. Male or female volunteer aged 18-50 years old
  2. Able to understand procedures and agree to participate in the study by giving written informed consent.
  3. Speaks fluent English.
  4. Not taking illicit drugs.
  5. No history of neurological problems.
  6. Eligible for MRI, including no metal in the body or body piercings that cannot be removed.

Exclusion Criteria:

  1. Current comorbid Axis 1 psychiatric disorder
  2. Women who are current pregnant or breastfeeding
  3. Lifetime diagnosis of any psychotic disorder, cognitive suicidal ideation, substance abuse or alcohol dependence, hoarding.
  4. Medications that act on the central nervous system that interfere with interpretation of the findings (e.g., painkillers, Adderall)
  5. Claustrophobia
  6. Patients who are unable to comply with procedures or assessments.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT03498599

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Contact: Joseph Dunsmoor, PhD 5124955114

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United States, Texas
The University of Texas at Austin Recruiting
Austin, Texas, United States, 78705
Contact: Joseph Dunsmoor, PhD    512-495-5114   
Sponsors and Collaborators
University of Texas at Austin

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Responsible Party: University of Texas at Austin Identifier: NCT03498599    
Other Study ID Numbers: UTfearconditioning
First Posted: April 13, 2018    Key Record Dates
Last Update Posted: April 13, 2018
Last Verified: April 2018
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: Yes
Plan Description: NIMH Data Archive
Supporting Materials: Study Protocol
Statistical Analysis Plan (SAP)
Informed Consent Form (ICF)
Time Frame: Less than 6 months after data is collected.
Access Criteria: We will upload data to the NIMH Data Archive and data will be accessible per their policy.

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by University of Texas at Austin:
fear conditioning
Additional relevant MeSH terms:
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Anxiety Disorders
Stress Disorders, Traumatic
Stress Disorders, Post-Traumatic
Phobic Disorders
Panic Disorder
Phobia, Social
Pathologic Processes
Mental Disorders
Trauma and Stressor Related Disorders