Brain Indices of Risk for Posttraumatic Stress Disorder (PTSD) After Mild Traumatic Brain Injury (mTBI)

Inclusion Criteria: 1. Injured while deployed or stateside 2. Must be diagnosed TBI positive or certified as TBI negative by a licensed medical practitioner using Department of Defense (DoD) criteria 3. For mTBI subjects, an initial score of 13-15 on the Glasgow Coma Scale 4. Aged 18-50 5. Defense Enrollment Eligibility Reporting System (DEERS) eligible Exclusion Criteria: 1. Unable or unwilling to provide informed consent and Health Insurance Portability and Accountability Act (HIPAA) authorization ("unable" includes cases in which the potential subject cannot read and understand English well enough to provide informed consent) 2. Penetrating head injury 3. Medical chart reveals a history of significant neurological condition(s) (reviewed on a case by case basis) 4. Diagnosis with or undergoing treatment for an illness that could affect brain function (reviewed on a case-by-case basis) 5. History of major psychiatric condition(s) that interfere with daily functioning as revealed in the medical chart or by the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID) 6. Record of drug or alcohol abuse or dependence in the past six months as documented in medical history review 7. Medical chart or SCID reveals current or lifetime PTSD diagnosis related to non-combat life events that occurred prior to most recent deployment