1. Mental Illness Research, Education, and Clinical Center, VA Puget Sound Health Care System (VA Puget Sound), Seattle, WA 98108, USA.
2. Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA 98195, USA.
3. VA Jamaica Plain, Department of Neurology, Boston University School of Medicine, Jamaica Plain, MA 02130, USA.
4. Department of Radiology, University of Washington, Seattle, WA 98195, USA.
5. Department of Radiology, University of Utah, Salt Lake City, UT 84132, USA.
6. Geriatric Research Education and Clinical Center, VA Puget Sound Health Care System, Seattle, WA 98108, USA.
7. Department of Medicine, University of Washington, Seattle, WA 98195, USA.
8. Department of Pharmacology, University of Washington, Seattle, WA 98195, USA.