Jonathan S. Emens, M.D., F.A.A.S.M., D.F.A.P.A.

  • Professor of Psychiatry, School of Medicine
  • Affiliate Faculty, Oregon Institute of Occupational Health Sciences
  • Clinical Director of Mental Health & Chief of Psychiatry, VA Portland Health Care System
  • Vice Chair for VHAPORHCS


Dr. Emens is a Professor of Psychiatry at Oregon Health & Science University. He received his B.A. from Oberlin College, M.D. from University of Massachusetts Medical School, and completed his Internship and Psychiatry Residency at OHSU.

Dr. Emens' clinical focus is on the diagnosis and treatment of sleep disorders in the Portland VA Sleep Medicine Program. He is board certified in Psychiatry and Sleep Medicine.

Dr. Emens’ research has focused on circadian rhythm sleep disorders (in particular, Non-24-Hour Sleep-Wake Rhythm Disorder), sleep and circadian physiology in mood disorders, and circadian physiology in sleep apnea and obesity.

Education and training

    • B.A., 1992, Oberlin College
    • M.D., 1998, University of Massachusetts Medical School
  • Residency

    • OHSU, Department of Psychiatry

Memberships and associations:

  • Distinguished Fellow
  • Sleep Research Society
  • American Psychiatric Association


Selected publications

  • Czeisler CA, Shanahan TS, Klerman EB, Martens H, Brotman DJ, Emens JS, Klein T, Rizzo JF.  Suppression of Melatonin Secretion in Some Blind Patients by Exposure to Bright Light.  New England Journal of Medicine 1995; 332: 6-11. PMID: 7990870
  • Czeisler CA, Duffy JF, Shanahan TL, Brown EN, Mitchell JF, Rimmer DW, Ronda JM, Silva EJ, Allan JS, Emens JS, Dijk DJ, Kronauer RE.  Stability, Precision, and Near-24-Hour Period of the Human Circadian Pacemaker.  Science 1999; 284: 2177-81. PMID: 10381883
  • Lewy AJ, Emens JS, Sack RL, Hasler BP, Bernert RA.  Low, but not high doses of melatonin entrained a free-running blind person with a long circadian period.  Chronobiology International 2002; 19: 649-658. PMID: 12069043
  • Emens JS, Lewy AJ, Lefler BJ, Sack RL.  Relative Coordination to Unknown “Weak Zeitgebers” in Free-Running Blind Individuals.  Journal of Biological Rhythms 2005, 20: 159-167. PMID: 15834112
  • Emens JS, Yuhas K, Rough J, Kochar N, Peters D, Lewy AJ. Phase Angle of Entrainment in Morning- and Evening-Types under Naturalistic Conditions. Chronobiology International 2009; 26: 474-493. PMID: 19360491
  • Emens JS, Lewy AJ, Kinzie JM, Arntz D, Rough J.  Circadian Misalignment in Major Depressive Disorder.  Psychiatry Research 2009; 168: 259-261. PMID:19524304
  • Emens JS, Lewy AJ, Laurie AL, Songer JB.  The Rest/Activity Cycle and the Melatonin Rhythm in Blind Free-runners Have Similar Periods.  Journal of Biological Rhythms 2010, 25: 381-384.  PMID: 20876818
  • Emens JS, Laurie AL, Songer JB, Lewy AJ.  Non-24-Hour Disorder in Blind Individuals Revisited: Variability and the Influence of Environmental Time Cues.  Sleep 2013, 36: 1091-1100. PMID: 23814347
  • Emens JS and Burgess HJ.  Effect of Light and Melatonin and Other Melatonin Receptor Agonists on Human Circadian Physiology.  Sleep Medicine Clinics 2015;10: 435-453.  PMID: 26568121
  • Emens JS and Eastman CI.  Diagnosis and Treatment of Non-24-h Sleep–Wake Disorder in the Blind.  Drugs 2017; 77: 637-650.  PMID: 28229310


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