Neuromodulation of the Fear Extinction Circuit Using Temporally and Anatomically Specific TMS in Humans
The University of Texas Health Science Center, Houston
Summary
This study aims to explore the mechanisms of how transcranial magnetic stimulation (TMS) impacts fear circuits. The overarching objectives are to understand how varying TMS parameters affect targeted brain regions in order to optimize its impact on enhancing fear extinction memory consolidation in a population with known fear extinction deficiencies: post-traumatic stress disorder (PTSD). 250 subjects will take part in this research study across UTHealth Houston. The study will include preliminary screenings, baseline visits, and experimental visits across four days
Description
The experiments proposed are aimed to understand how timing and location of transcranial magnetic stimulation (TMS) in humans will impact their ability to reduce conditioned fear responses and impact the activation of their brain regions involved in fear regulation. The researchers will use a novel TMS approach to vary timing and location of its delivery so that the researchers can characterize and establish best time and location to obtain optimal impact on fear inhibition, and then test these parameters in PTSD patients and see if such can rescue extinction deficits in PTSD. The anticipated…
Eligibility
- Age range
- 18–70 years
- Sex
- All
- Healthy volunteers
- Yes
Inclusion Criteria: * Willing and able to provide informed consent. * Inclusion Criteria for PTSD Subjects - Diagnosis of current PTSD * Inclusion Criteria: Healthy Controls (HC) - no current psychiatric disorders ("Axis I" disorders) Exclusion Criteria: * Lifetime history of seizure or significant head trauma or other significant neurologic disease (e.g., tic disorder) * History of serious/significant psychiatric diagnoses ("Axis I" diagnoses) * Current significant suicidal ideation, plan or intent or suicidal behavior in past 6 months based on CSSRS and clinical judgment or Self-injurious…
Interventions
- DeviceTranscranial magnetic stimulation (TMS)
Research subjects will undergo non-invasive TMS, with a frequency of 20Hz and intensity of 120% of their resting motor threshold (rMT) at varying time points and locations.
- BehavioralFear Conditioning and Extinction Paradigm
Participants will undergo a 3-day experimental paradigm. On day 1, participants will undergo a resting-state and structural scans in the fMRI scanner. The data from this scan will be used to determine the specific location of the TMS target for each participant. And participants will be aversively conditioned to two cues in the fMRI scanner. Task based and resting-state scans will occur on this day. On day 2, subjects will undergo extinction training outside of the scanner where one of the conditioned cues will be paired with TMS in a temporally and anatomically specific manner. A resting-state scan will occur before and after inside the scanner. On day 3, conditioned cues will be presented during the extinction recall phase of the study. This phase will be conducted in the fMRI scanner. Task-based and resting-state scans will occur on this day.
Location
- UTHealth HoustonHouston, Texas