Neuroimaging Memories of Fear and Safety in the Human Brain
- Conditions
- PTSDFear Anxiety
- Interventions
- Behavioral: Fear conditioning
- Registration Number
- NCT04975009
- Lead Sponsor
- University of Texas at Austin
- Brief Summary
The purpose of this research is to use functional magnetic resonance imaging (fMRI) to investigate how the brain forms associations between neutral and negative stimuli. The ultimate goal is to understand the neural systems involved in regulating negative emotional responses to fearful stimuli.
- Detailed Description
This study uses functional magnetic resonance imaging (fMRI) to investigate how the brain forms associations between neutral stimuli and a mildly uncomfortable electrical stimulation to the wrist. Referred to as Pavlovian fear conditioning. The goal is to compare brain activity between individuals with posttraumatic stress disorder (PTSD) and healthy control subjects without PTSD. PTSD is characterized by excessive fear and anxiety, including in harmless situations. The data here will help us better understand dysregulation in neural circuitry involved in fear recovery, which has implications for improving treatment.
Recruitment & Eligibility
- Status
- RECRUITING
- Sex
- All
- Target Recruitment
- 240
Not provided
Not provided
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description PTSD group Fear conditioning Participants will be screened and diagnosed using typical screening procedures and diagnostic criteria (e.g., the clinically administered PTSD scale). Participants also screened for contraindications for MRI. The learning paradigm inside the MRI scanner occurs over 3 days. The first two days are consecutive (back-to-back) and the third MRI visit is 1 month later. Participants are asked to look at a screen and listen to simple tones over headphones, while the experimenter measures brain activity and physiological measures of arousal (e.g., sweating from sensors on the hand). These visits will be scheduled within two weeks from the baseline and assessment visit. Healthy control group Fear conditioning Participants will be healthy adults without a history of psychiatric illness. Participants also screened for contraindications for MRI. The learning paradigm inside the MRI scanner occurs over 3 days. The first two days are consecutive (back-to-back) and the third MRI visit is 1 month later. Participants are asked to look at a screen and listen to simple tones over headphones, while the experimenter measures brain activity and physiological measures of arousal (e.g., sweating from sensors on the hand). These visits will be scheduled within two weeks from the baseline and assessment visit.
- Primary Outcome Measures
Name Time Method Change in physiological arousal throughout the experimental phases, compared between healthy controls and PTSD participants through study completion, an average of 1 month. Skin conductance responses measure sweating throughout the experiment. We compare the magnitude of this response during each phase of the experiment between groups.
Change in functional MRI data in fear-learning circuitry throughout the experimental phases, compared between healthy controls and PTSD participants through study completion, an average of 1 month. Participants undergo scanning on a 3-Tesla MRI during all experimental phases. Blood-oxygen-level-dependent (BOLD) signal in key brain regions will be compared between groups.
- Secondary Outcome Measures
Name Time Method Individual differences in brain-behavior responses through study completion, an average of 1 month. Individual participants arousal, as well as trait variable of anxiety and symptom severity, will be used as a covariate in neuroimaging analyses to assess brain-behavior correlations.
Trial Locations
- Locations (2)
The University of Texas at Austin
🇺🇸Austin, Texas, United States
Biomedical Imaging Center
🇺🇸Austin, Texas, United States