Actively Recruiting
Individualized Computational Assessment of the Effects of GABA Receptor Modulation in Posttraumatic Stress Disorder
Led by VA Office of Research and Development · Updated on 2025-07-14
150
Participants Needed
1
Research Sites
N/A
Total Duration
On this page
AI-Summary
What this Trial Is About
Researchers are studying Veterans with posttraumatic stress disorder (PTSD) to understand how different medications affect individuals with varying symptoms. The study focuses on a subgroup of Veterans with high anxious arousal who might respond to medications that enhance gamma-aminobutyric acid (GABA) signaling. The aim is to validate a clinical test using computational and neuroimaging methods combined with lorazepam, a GABA modulator, to better target treatments to these Veterans. Participants will receive two single doses in a randomized order: one dose of lorazepam 1 mg and one dose of placebo, each given during separate testing sessions spaced one week apart. During each session, participants will perform a computational goal-directed control task called the rapid assessment of motor processing (RAMP) to measure dynamic inhibition, which relates to GABA signaling. Functional neuroimaging will also be used to study brain activity related to GABAergic influence. Throughout the study, participants will be assessed on dynamic inhibition and neural activity about 1.5 hours after dosing. They will also complete questionnaires measuring fear levels. The study involves a randomized, quadruple-masked crossover design to compare the effects of lorazepam and placebo. Safety and eligibility will be closely monitored, and the total study participation includes these two testing sessions with a washout period between them.
CONDITIONS
Brief Title
Computational Assessment of GABA Receptor Modulation in PTSD
Who Can Participate
Eligibility Criteria
You may qualify if you...
- Veteran
- Between 18 and 65 years of age, inclusive
- Willing to abstain from alcohol 24 hours before and after each testing session
- Able and willing to give written informed consent and comply with study requirements
- Current diagnosis of PTSD based on CAPS-5 (for PTSD group)
You will not qualify if you...
- Uncontrolled significant neurologic, cardiovascular, pulmonary, hepatic, renal, metabolic, gastrointestinal, urologic, immunologic, endocrine, or psychiatric disorders that may affect participation or study results
- Pregnancy or lactation
- History of chronic psychotic disorder or bipolar disorder type I
- Current moderate or severe substance use disorder
- Positive urine test for drugs of abuse at screening and before dosing (with specific retesting rules for THC)
- Signs of drug or alcohol intoxication or withdrawal
- Current use of benzodiazepines or opioids
- Use of medications with unsafe interaction with lorazepam
- Past intolerance or allergy to lorazepam or benzodiazepines
- Active suicidal ideation or high suicidal risk
- History of traumatic brain injury with loss of consciousness over 30 minutes
- Insufficient English proficiency or other impairments preventing consent or study participation
- Contraindications to MRI or non-right-handedness (for fMRI participants)
- Axis I disorder in healthy control group
- Any other condition deemed unsafe or interfering by the study physician
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 - 2 weeks including a 1 week washout period between sessions
Participants receive a single dose of lorazepam or placebo in separate sessions to assess the effects of GABA receptor modulation using a computational task and fMRI.
2 visits (in-person), one for each dosing session
Trial Site Locations
Total: 1 location
1
VA San Diego Healthcare System, San Diego, CA
San Diego, California, United States, 92161-0002
Actively Recruiting
Research Team
V
Vitaliana R Vasquez, BA
How is the study designed?
Study Type
INTERVENTIONAL
Masking
QUADRUPLE
Allocation
RANDOMIZED
Model
CROSSOVER
Primary Purpose
BASIC_SCIENCE
Number of Arms
2
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