Neuroimaging of Pavlovian Fear Conditioning Processes in Patients With Pathological Anxiety
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|ClinicalTrials.gov Identifier: NCT03498599|
Recruitment Status : Recruiting
First Posted : April 13, 2018
Last Update Posted : April 13, 2018
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|
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.
|Study Type :||Interventional (Clinical Trial)|
|Estimated Enrollment :||40 participants|
|Intervention Model:||Parallel Assignment|
|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|
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.
The shock is omitted during standard extinction
Behavioral: Standard Extinction
During standard fear extinction the expected aversive outcome is omitted.
- 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.
- 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
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 ClinicalTrials.gov identifier (NCT number): NCT03498599
|Contact: Joseph Dunsmoor, PhDemail@example.com|
|United States, Texas|
|The University of Texas at Austin||Recruiting|
|Austin, Texas, United States, 78705|
|Contact: Joseph Dunsmoor, PhD 512-495-5114 firstname.lastname@example.org|