1. Mental Illness Research, Education, and Clinical Center (MIRECC), VA Puget Sound Health Care System (VA Puget Sound), Seattle, Washington, USA.
2. Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA.
3. Department of Radiology, University of Washington, Seattle, Washington, USA.
4. Department of Rehabilitation Medicine, School of Medicine, University of Washington, Seattle, Washington, USA.
5. Geriatric Research, Education, and Clinical Center (GRECC), VA Puget Sound Health Care System (VA Puget Sound), Seattle, Washington, USA.
6. United States Army Special Operations Command, Fort Liberty, North Carolina, USA.
7. Matthew Gfeller Center, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, Stallings-Evans Sports Medicine Center, Chapel Hill, North Carolina, USA.
8. Division of Biostatistics, Department of Family Medicine & Public Health, University of California San Diego, La Jolla, California, USA.