Control Network Neuromodulation to Enhance Cognitive Training in Complex Traumatic Brain Injury

Inclusion Criteria: There will be no gender restrictions with regard to sample inclusion. Veterans and Warfighters will be enrolled in this study if they 1) are aged 18-59; 2) have suffered a mild TBI with documented evidence of alteration in neurological functioning or loss of consciousness (LOC) which was less than 30 minutes; 3) were injured between 3 months and 5 years ago; 4) experienced less than 24 hours of post-traumatic amnesia (PTA); 5) have subjective post-TBI cognitive deficits as assessed by the NSI, with at least 1 of 4 cognitive symptoms at a score of 3 or higher (severe disturbance) or at least 2 of 4 cognitive symptoms at a score of 2 or higher (moderate disturbance). This is the target population as identified by the grant mechanism, with chronic cognitive impairments from mild traumatic brain injury. The age range of 18-59 years was selected because the investigators did not want to include developmental processes in analyses and by 18 years old, many major neurodevelopmental changes in the brain will have taken place. Using similar rationale, the investigators chose to include participants up to the age of 59 because they do not want to include advancing age-related brain changes in our analyses. They will also be 6) fluent in English, as the testing and intervention are all conducted in English; and 7) will have been on stable doses of any psychotropic medications for the past 2 months, so as to avoid confounding of results by medication effects. It is expected that the sample included in this study will reflect the demographics of the greater Albuquerque and Twin Cities metropolitan communities. Exclusion Criteria: Veterans will be excluded from participation in this study if there is 1) a prior history of other neurological disease or any history of seizures beyond immediate post-traumatic seizure, so as to reduce risk of exacerbation of epilepsy or other neurological symptoms; 2) history of psychosis, so as to reduce risk of psychiatric decompensation; 3) history of current or recent (within two years) substance/alcohol dependence, to reduce confounding effects on cognition; 4) any discontinuity in skull electrical conductivity (i.e., unhealed burr holes in scalp) or artificially constructed (metal or plastic) craniotomy cover, to reduce risk of unimpeded electrical current; 5) presence of any implanted metal or electrical device (e.g. pacemaker), to reduce risk of heating during MRI, or device malfunction during neuromodulation; 6) recent medical hospitalization (within three weeks), to reduce risk of medical decompensation during the study; 7) any condition that would prevent the participant from completing the protocol, such as significant agitation; 8) appointment of a legal representative, as assessed via direct inquiry of the participant or a designated trusted other, to avoid coercion of a vulnerable population; 9) any significant hardness of hearing or blindness that would make completing the cognitive training not possible; 10) any ongoing litigation related to TBI, to prevent interference with legal proceedings; 11) any other contraindication to exposure to strong magnetic fields or MRI, such as severe claustrophobia; 12) pregnant women will be excluded as the effects of MRI and brain stimulation on developing fetuses are unknown; 13) membership in an identified vulnerable population, including minors, and prisoners, and adults unable to consent due to cognitive impairment will be excluded, as they will be unlikely to be able to complete study procedures. Prisoners will be excluded from the study to avoid coercion; 14)received a Glasgow coma scale (GCS) less than 13 or greater than 15 upon ED admission, if available in patient's records. The investigators do not intend to include adults who are unable to consent in this study. The investigators do not intend to include individuals who are not yet adults (infants, children, teenagers) in this study. The investigators do not intend to include pregnant women in this study. The investigators do not intend to include prisoners in this study.