Detection and Amelioration of Gamma Oscillation Abnormalities in Blast-Related Brain Injury

Combat Veterans of post-9/11 conflicts have experienced serious cognitive and emotional problems resulting from exposure to blasts. Recent work suggests that a critical factor influencing the consequences of blast exposure is distance from the blast, rather than the presence or absence of concussion symptoms. Exposure to blasts from a distance of \10 m. So far, the effects of blast-related brain injury on the brain are poorly understood, as to date the effects of blast exposure have received little research focus. The investigators propose to use oscillations in the gamma band (30-100 Hz) of the electroencephalogram (EEG; brain waves) to detect and remediate neural circuit dysfunction related to blast injury in Veterans. If successful, this project could lead to new approaches to detect and remediate the effects of blast exposure on Veterans and aid in their functional recovery.

Inclusion Criteria: * Research participants will be 50 veterans * Ages 18-65 years * Have experienced blast exposure * Recruited from the VA Translational Research Center for TBI and Stress Disorders (TRACTS) at the VA Boston Healthcare System (VABHS) * Half of the participants will have experienced blast exposure from a Close distance (\10 m) * These groups will be matched on age and female/male ratio Exclusion Criteria: Initial exclusion criteria for TRACTS are: * History of neurological illness * Huntington's * Parkinson's * dementia, etc * History of seizure disorders unrelated to head injury * Current diagnosis of schizophrenia, bipolar, or other psychotic disorder * Self-reported severe depression or anxiety requiring hospitalization overnight, or current active homicidal and/or suicidal ideation with intent requiring crisis intervention * Cognitive disorder due to general medical condition other than TBI * Unstable psychological diagnosis (suspected psychotic or personality disorder) that would interfere with accurate data collection, determined by consensus of at least three doctoral-level psychologists. Additional exclusion criteria for participants in the present project will be: * Current alcohol or drug dependence, or abuse within the last 6 months (DSM-IV criteria) * Hearing impairments as assessed by audiometry