A Mechanistic Trial of the Neurobiology of Extinction Learning and Intraparietal Sulcus Stimulation
University of Pennsylvania
Summary
This study will be the first of its kind to explore the impact of continuous theta burst stimulation (cTBS) to the intraparietal sulcus (IPS) on arousal symptoms among patients with posttraumatic stress disorder (PTSD). The investigators will demonstrate that IPS cTBS results in significant reduction in arousal (measured by startle response) compared to sham cTBS, that IPS cTBS interacts with extinction training to further improve arousal, and that there is a dose/response effect of cTBS on arousal. The investigators will also demonstrate that IPS cTBS significantly improves retention of extinction learning, the experimental analogue of exposure therapy.
Description
Posttraumatic stress disorder (PTSD) is associated with alterations in arousal that do not respond well to evidence-based practices. Patients with PTSD tend to fall into one of two groups in extinction training (and in exposure therapy): 1) over-engagers, where arousal is too high; and 2) under-engagers, where patients are so worried about becoming upset that they distract themselves from the task (which prevents learning). In this mechanistic clinical trial, the investigators will evaluate a strategy to augment extinction training with neuromodulation to reduce arousal and improve extinction…
Eligibility
- Age range
- 18–60 years
- Sex
- All
- Healthy volunteers
- No
Inclusion Criteria: * 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 Exclusion Criteria: * 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
Interventions
- DeviceContinuous Theta Burst Stimulation to the Intraparietal Sulcus
Continuous Theta Burst Stimulation delivered to the Intraparietal Sulcus
- DeviceSham Continuous Theta Burst Stimulation
Sham Continuous Theta Burst Stimulation
Location
- Center for the Treatment and Study of Anxiety, University of PennsylvaniaPhiladelphia, Pennsylvania