Cerebral Autoregulation, Brain Perfusion, and Neurocognitive Outcomes After Traumatic Brain Injury

Inclusion Criteria:

* Documented/Verified TBI (ACRM Criteria) (eg, motor vehicle (MV) occupant, MV pedestrian/cyclist, fall, other non-intentional, violence/assault)
* A documented moderate to severe TBI defined as: Glasgow Coma Scale (GCS) \< 13, or loss of consciousness (LOC) \> 30 minutes, or posttraumatic amnesia (PTA) \> 24 hours or intracranial neuroimaging abnormalities
* Between the age 18 - 80 year-old
* ≤ 1 week postinjury
* Acute brain CT for clinical care
* Admitted to the hospital for TBI
* Visual acuity/hearing adequate for testing
* Fluent in English or Spanish
* Patient or LAR ability to provide informed consent

Exclusion Criteria:

* Age greater or less than the range 18-80 years
* Significant polytrauma that would interfere with follow-up and outcome assessment
* Major debilitating baseline mental health disorders (e.g., schizophrenia, bipolar disorder, severe depression with active suicidal thoughts at the time of evaluation) that would interfere with follow-up and the validity of outcome assessment.
* Major debilitating neurological disease (e.g., stroke, CVA, dementia, tumor) impairing baseline awareness, cognition, or validity of follow-up and outcome assessment.
* Significant history of pre-existing conditions that would interfere with follow-up and outcome assessment (e.g., active substance abuse, alcoholism, HIV/AIDs, end-stage cancers, learning disabilities, developmental disorders)
* Patients on psychiatric hold
* Prisoners or patients in custody
* Pregnancy in female subjects
* Low likelihood of follow-up (e.g., participants or family indicating low interest, residence in another state or country, homeless or lack of reliable contacts)
* Current participant in an interventional trial (e.g., drug, device, behavioral)
* Penetrating TBI
* Spinal cord injury with ASIA score of C or worse
* Contraindications to MRI