Actively Recruiting
A Mechanistic Trial of the Neurobiology of Extinction Learning and Intraparietal Sulcus Stimulation
Led by University of Pennsylvania · Updated on 2025-10-30
120
Participants Needed
1
Research Sites
13 weeks
Total Duration
On this page
AI-Summary
What this Trial Is About
Researchers are investigating the effects of continuous theta burst stimulation (cTBS) to the intraparietal sulcus (IPS) on arousal symptoms in patients with posttraumatic stress disorder (PTSD). This mechanistic clinical trial aims to show that IPS cTBS reduces arousal, measured by startle response, better than sham cTBS, enhances extinction training effects, and improves retention of extinction learning, which is similar to exposure therapy. The study also seeks to find the optimal dose of IPS cTBS and understand its neural mechanisms through brain imaging. Participants will be randomly assigned to receive either real IPS cTBS or sham cTBS. The cTBS will be delivered using a device targeting the IPS at a set intensity. Some participants will also undergo extinction training or neutral training to evaluate combined effects. The treatment involves multiple sessions over a defined period, including intensity adjustments to find the best dose. Brain scans such as resting state fMRI will be performed to assess neural changes. During the study, participants will undergo several assessments including electromyography to measure startle response on specific days, subjective distress ratings, and brain imaging. Researchers will monitor changes in arousal and retention of extinction learning over time. This study includes detailed safety and eligibility evaluations, and participants will be followed up for several weeks to observe lasting effects. Total participation time spans multiple visits with evaluations before, during, and after treatment.
CONDITIONS
Brief Title
A Mechanistic Trial of the Neurobiology of Extinction Learning and Intraparietal Sulcus Stimulation
Who Can Participate
Eligibility Criteria
You may qualify if you...
- Adult aged 18-60
- Meets Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria for PTSD according to the Clinician-Administered PTSD Scale for DSM-5
- No metal implants
You will not qualify if you...
- Pregnancy
- Seizure disorder or epilepsy
- Increased risk of seizure
- Non-English speaking
- Any medical condition that increases risk for fMRI or cTBS
- Medical implant
- Hearing loss sufficient to interfere with startle
- Claustrophobia
- Recent medication or therapy changes (in the past 8 weeks)
- Current severe substance use disorder
AI-Screening
AI-Powered Screening
Complete this quick 3-step screening to check your eligibility
Your Study Journey
Duration - 2 to 4 weeks
Participants are screened for eligibility to participate in the trial.
1 visit (in-person)
Duration - 5 days
Participants receive continuous theta burst stimulation or sham stimulation targeted to the intraparietal sulcus along with extinction or neutral training to evaluate effects on arousal and learning.
Daily visits on Days 2, 4, and 5 including stimulation and training sessions
Duration - Up to 35 days
Participants undergo follow-up assessments including startle response, subjective distress, negative outcome expectancy, and fMRI scans to evaluate neural changes and retention of extinction learning.
Visits on Days 34 and 35 for follow-up assessments and fMRI
Trial Site Locations
Total: 1 location
1
Center for the Treatment and Study of Anxiety, University of Pennsylvania
Philadelphia, Pennsylvania, United States, 19104
Actively Recruiting
Research Team
L
Lily A Brown, PhD
How is the study designed?
Study Type
INTERVENTIONAL
Masking
TRIPLE
Allocation
RANDOMIZED
Model
SINGLE_GROUP
Primary Purpose
BASIC_SCIENCE
Number of Arms
2
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