for people ages 18-50 (full criteria)
healthy people welcome
study started
estimated completion



The ability to regulate impulses enables us to plan for the future, to maintain focus in the face of distractions (i.e. to encode memories), and to manage emotions. This self regulation can be compromised in individuals who have a history of mild traumatic brain injury and co-occurring disorders. In this study the investigators are using functional MRI scanning to understand how memory and self regulation are expressed in the brains of people with a history of mild traumatic brain injury. The investigators are also testing whether the medication tolcapone may improve memory and self regulation.


In this randomized, double-blind, placebo-controlled, crossover cognitive neuroscience study, the investigators are evaluating whether the COMT inhibitor tolcapone impacts memory and self regulation, as measured both behaviorally (via cognitive testing) and neurophysiologically (via functional MRI).


Mild Traumatic Brain Injury concussion traumatic brain injury MRI memory tolcapone Brain Injuries Brain Injuries, Traumatic Brain Concussion


You can join if…

Open to people ages 18-50

  • Veteran ages 18-50 and in general good health;
  • Able to read English at a 6th grade level;
  • Able to provide written informed consent;
  • Normal or corrected to normal visual acuity;
  • Stable doses of all medications (2 weeks or greater);
  • History of mild traumatic brain injury greater than 6 months prior to participation

You CAN'T join if...

  • Contraindications to MRI scanning;
  • Inability to complete basic fMRI requirements;
  • History of brain surgery or penetrating brain injury;
  • Uncontrolled blood pressure (low or high);
  • Contraindications to tolcapone use;
  • Use of medications or drugs with dopamine-related actions within 30 days;
  • Active substance abuse or dependence;
  • Clinically severe medical illness requiring treatment;
  • History of psychiatric hospitalization (past 1 year) or suicide attempt (past 5 years);
  • Seizures greater than 4 weeks after TBI event or seizures requiring active treatment;
  • History of brain tumor, stroke, Alzheimer's disease, aneurysm rupture, or multiple sclerosis;
  • History of schizophrenia, ADHD or psychiatric diagnosis EXCEPT depression or PTSD


  • VA Northern California Health Care System, Mather, CA
    Sacramento California 95655 United States


accepting new patients by invitation only
Start Date
Completion Date
VA Office of Research and Development
Study Type
Last Updated