Advanced MRI Applications for Mild Traumatic Brain Injury

Segment 1: Inclusion Criteria for mTBI subjects Subjects included in the main part of this study (Segment 1) will: 1. Be aged ≥15 and ≤50 years old at the time of enrollment; 2. Be diagnosed with mTBI according to the standard diagnostic procedures at the investigational site in a timeframe that meets enrollment criteria for enrollment in one of the first two intervals of the study, as follows: 1. Meets criteria for enrollment in Encounter 1 (within 72 hours) OR 2. Meets criteria for enrollment in Encounter 2 (within 8±2 days) 3. Be capable of sufficiently clear communication to allow the subject to provide written informed consent, or assent with parental or guardian consent for minors as described in Section 6.3 - Protection of Vulnerable Subjects, for participation in all parts of the study. Segment 1: Exclusion Criteria for mTBI subjects Subjects will be excluded that have: 1. Loss of consciousness (LOC) ≥15 minutes; 2. Posttraumatic amnesia lasting ≥24 hr following a recent TBI event; 3. Diagnosis of moderate to severe TBI or GCS \<13; 4. Structural brain injury indicated by previous neuroimaging findings; 5. Previous history of moderate to severe TBI; 6. Any previous history of mild TBI within the past 12 months; 7. Previously diagnosed brain white matter disease; 8. History of seizures within the past 10 years; 9. History of self-reported illicit drug abuse (except marijuana) in past 10 years; 10. History of alcohol abuse or dependence (per DSM-IV-TR Diagnostic Criteria); 11. Current primary Axis I or II psychiatric disorders, except for disorders classified as minor and not expected to impact study conduct or integrity (as detailed in Appendix D - Screening for Exclusion based on Axis I or II Disorders): 12. History of brain mass 13. History of neurosurgery 14. History of stroke 15. History of dementia 16. Known cognitive dysfunction 17. Known structural brain disease or malformation 18. Current anti-psychotic or antiepileptic medication usage 19. That are unable or unwilling to complete study procedures accurately or have any conflict of interest that could affect study results, in the opinion of the investigator; 20. Contraindications to MRI scanning, including: 1. Current or suspected pregnancy per site clinical practice; 2. Other conditions that may constitute a hazard to the subject during study participation, determined by the investigator; 3. Inability to comply with any part of the site's MR safety policy. Inclusion Criteria for Non-TBI subjects (Segment 2) All included subjects will: 1. Aged ≥15 and ≤50 years old at the time of enrollment; 2. Be well matched to one or more mTBI patients in Segment 1, in the opinion of the Principal Investigator, with regards to: 1. Age, 2. Gender, 3. Sociodemographic characteristics, and 4. Handedness. 3. Be capable of sufficiently clear communication to allow the subject to provide written informed consent, or assent with parental or guardian consent for minors as described in Section 6.3 - Protection of Vulnerable Subjects, for participation in all parts of the study. Exclusion Criteria for Non-TBI subjects (Segment 2) Subjects will be excluded that: 1. Are currently pregnant based on subject self-report of pregnancy status; 2. Are currently enrolled in another Segment of this study; 3. Require medical care that would be adversely affected or delayed by participating, in the opinion of a physician investigator; 4. Prior diagnosis of mild TBI within the past 12 months; 5. Have structural brain injury indicated by previous neuroimaging findings; 6. Previous history of moderate to severe TBI within the past 10 years; 7. Previously diagnosed brain white matter disease; 8. History of seizures within the past 10 years; 9. History of illicit drug abuse (except marijuana) within the past 10 years 10. History of alcohol abuse or dependence (per DSM-IV-TR Diagnostic Criteria); 11. Current primary Axis I or II psychiatric disorders, except for disorders classified as minor and not expected to impact study conduct or integrity (as detailed in Appendix D - Screening for Exclusion based on Axis I or II Disorders): 12. History of brain mass; 13. History of neurosurgery; 14. History of stroke; 15. History of dementia; 16. Known cognitive dysfunction;