BiographyDr. Welsh earned his undergraduate degree at Stanford University, where he began a long-standing interest in circadian rhythms and sleep. In graduate work at Harvard Medical School, he discovered that individual brain cells can generate circadian rhythms. He received a Ph.D. in Neurobiology and an M.D. from Harvard in 1997, then completed a residency in general psychiatry at Western Psychiatric Institute and Clinic, in Pittsburgh. After two years as a postdoctoral research fellow, he joined the faculty of the UCSD Department of Psychiatry in 2003. He is currently an Associate Professor in the Department, and a Staff Psychiatrist at the VA San Diego Healthcare System.
Research InterestsIn mammals, a hierarchical system of circadian clock cells in the brain and throughout the body orchestrates daily patterns of physiology and behavior. These daily patterns persist under constant conditions as "circadian rhythms". Dr. Welsh studies circadian rhythms in single cells using bioluminescence imaging to monitor clock gene expression. He is interested in the autonomy, heterogeneity, and coupling of cellular circadian clocks, particularly the "master" clock cells of the brain, the neurons of the suprachiasmatic nucleus. He is also interested in how defects in these mechanisms may contribute to sleep and circadian rhythm disorders in humans.
Clinical FocusDr. Welsh is a Staff Psychiatrist at the VA San Diego Healthcare System. He practices general adult psychiatry in the mood disorders clinic.