Faculty Profile

Division of Sleep Medicine, Brigham and Women's Hospital
Circadian Physiology Program
Harvard Work Hours Health and Safety Group

The Circadian Physiology Program focuses on basic and applied aspects of human circadian biology. Our translational approach includes use of a range of techniques including epidemiology, field-based physiological studies and inpatient intensive physiological monitoring. We have a particular interest in human circadian photoreception and the effects of light on the circadian pacemaker and other non-image forming responses. Our studies include investigations of the effects of timing, duration, intensity and wavelength of light exposure on circadian resetting, melatonin suppression and the acute alerting effects of light. We also study visually impaired individuals under field and laboratory conditions to examine the effects of the severity and type of blindness on circadian photoreception, the periodicity of the circadian pacemaker and development of circadian rhythm sleep disorders. These basic studies have led to the development of novel therapeutic strategies to treat non-24-hour sleep wake disorder, Advanced- and Delayed Sleep Phase Syndrome with appropriately-timed melatonin administration in blind patients. We have also recently begun to examine the role of visual impairment on endocrinology and breast cancer risk in blind women.

With the Harvard Work Hours Health and Safety Group, we assess the impact of extended work hours on health and safety of workers and the public. Our studies include the development of interventions that reduce extended duration work hours, fatigue and medical errors in hospital residents, and the implementation of large-scale occupational fatigue management and sleep disorders screening programs in several police forces nationwide.

Undergraduate students
University of Surrey, UK
Laura J. Butler, 1997; Sophie A. Rocks, 1998; Vanessa Sands, 1998; Charlotte E. Killer, 1999; Ourania Kosti, 1999; Amina Baksh, 1999; Marina Tsaoussouglou, 2004; Matthew Hurst, 2004; Mia Jacobsen, 2004

Imperial College, UK
Theresa Momberger, 1999; Victoria L. Revell, 2000

Harvard University
Clark J. Lee, 2003; Naila Ramji, 2007-date

Postgraduate students
University of Surrey, UK
Anna Zachirou, Masters student, 2000

Brigham and Women’s Hospital
Joseph T. Hull, Graduate student, 2002-date;
Shana E. McCormack, M.D., Masters student, 2002-date;
Erin E. Evans, Graduate student, 2004-date;
Christopher Pechacek,  Masters student (in collaboration with MIT), 2006-date;
Ahuva Y. Segal, Graduate student (in collaboration with Monash University), 2007-date
Catherine J. Hanley, Masters student (in collaboration with University College Dublin), 2007-date

Fellows
Joshua J. Gooley, Ph.D., Post-doctoral fellow, 2005-date
Adriana Lira-Oliver, D.Des., Post-doctoral fellow, 2007
Melanie Rüger, Ph.D., Post-doctoral fellow, 2007-date
Eliza Van Reen, Ph.D., Post-doctoral fellow, 2007-date

Dept of Defense PI: S.W. Lockley, PhD, Reproductive and hormonal risk factors for breast cancer in blind women

NSBRI/NASA PI: G.C. Brainard, PhD, Optimizing light spectrum for long duration space flight

NIH/NCCAM PI: PI: S.W. Lockley, PhD, Mechanism underlying the effects of blue light in humans

NIH/NIJ PI: C.A. Czeisler, PhD, MD, Testing the effectiveness of a comprehensive police fatigue management program

NIH/CDC PI: C.A. Czeisler, PhD, MD, Sleep disorders management, health and safety in police

NIH/AHRQ PI: C.P. Landrigan, MD, Implementing reduced work hours for all ICU staff to improve patient safety

NIH/NINDS PI: C.A. Czeisler, PhD, MD, Photic and nonphotic input to the human circadian system

NIH/NIOSH PI: E.S. Schernhammer, MD, Effects of light at night on the circadian system in nurses

NIH/NIMH PI: C.A. Czeisler, PhD, MD, Treatment of circadian rhythm sleep disorders with bright light

ResMed Foundation. PI: S.W. Lockley, PhD, Testing the effectiveness of a comprehensive police fatigue management program “Operation Healthy Sleep”.

NHMRC (Australia). PI: S.M.W. Rajaratnam, PhD. Acute alerting effects of daytime light exposure to specific wavelengths of light

NIH/NINDS: PI: C.A. Czeisler, PhD, MD, Desensitization of circadian responses to light

NHS (UK). PI: F.C. Cappuccio, MD. Effects on patient safety and physician well-being of implementing an EWTD-compliant rota reducing junior doctors’ weekly work hours from 56 to 48

NASA. PI: G.C. Brainard, PhD. Blue light for enhancing alertness in space missions.

ResMed Foundation. PI: S.W. Lockley, PhD, Assessment of AHI by ApneaLink under laboratory and home-based conditions in police officers with and without obstructive sleep apnea.

AFOSR. PI: D. Adams. Short wavelength countermeasure for circadian desynchrony

NSBRI: PI:  S.W. Lockley, PhD, Characteristics of light exposure necessary for development of optimal countermeasures to facilitate circadian adaptation and Enhance alertness and cognitive performance in space.

Faculty, Harvard University MCB186 Circadian Biology
Co-Director, Harvard University NSF Chautauqua Course for College Teachers Circadian Biology
Faculty, Sleep Medicine Special Study Module, Warwick Medical School, UK

In the News
Researchers discover second light-sensing system in human eye, 2007 article in Harvard Science
When the blues keep you awake, 2006 article in the Harvard Gazette
Overworked interns prone to medical errors, 2004 article in the Harvard Gazette
When light has you singing the blues, 2003 article in the Harvard Gazette

Cappuccio FP, Lockley SW. Safety and the flying doctor. (Letter).
British Medical Journal. 2008; 336 (7637): 218.

Zaidi FH, Hull JT, Peirson SN, Wulff K, Aeschbach D, Gooley JJ, Brainard GC, Gregory-Evans K, Rizzo III JF, Czeisler CA, Foster RG, Moseley MJ, Lockley SW. Short-wavelength light sensitivity of circadian, pupillary, and visual awareness in humans lacking an outer retina.
Current Biology. 2007 Dec 18;17(24):2122-8. [PMID: 18082405 - in process]

Zeitzer JM, Duffy JF, Lockley SW, Dijk D-J, Czeisler CA. Plasma melatonin rhythms in young and older humans during sleep, sleep deprivation, and wake.
Sleep. 2007 30(11):1437-1443. [PMID: 18041478 - in process]

Lockley SW, Barger LK, Ayas NT, Rothschild JM, Czeisler CA, Landrigan CP. Effects of healthcare provider work hours and sleep deprivation on safety and performance.
Jt Comm J Qual Patient Saf. 2007; 33(11, Suppl 1): 7-18. [PMID:18173162 - in process]

Landrigan CP, Czeisler CA, Barger LK, Ayas NT, Rothschild JM, Lockley SW. Reducing fatigue-related errors and injuries in healthcare: Effective implementation of work hour limits and systemic improvements.
Jt Comm J Qual Patient Saf. 2007; 33(11, Suppl 1): 19-29. [PMID: 18173163 - in process]

Lockley SW, Arendt J, Skene DJ. Visual impairment and circadian rhythm disorders. Dialogues Clin Neurosci. 2007; 9(3):301-314. [PMID: 17969867]

Stevens RG, Blask DE, Brainard GC, Hansen J, Lockley SW, Provencio I, Rea MS, Reinlib LE. The role of environmental lighting and circadian disruption in cancer and other diseases.
Environ Health Perspectives. 2007; 2007;115(9):1357-62.  [PMID: 17805428]

Lockley SW. Safety considerations for the use of blue-light blocking glasses in shift-workers.
J Pineal Res. 2007;42(2): 210-211. [PMID: 17286754]

Lockley SW, Landrigan CP, Barger LK, Czeisler CA; Harvard Work Hours Health and Safety Group. When policy meets physiology: the challenge of reducing resident work hours.
Clinical Orthopaedics and Related Research. 2006 Aug;449:116-27. Review. [PMID: 16770285]

Lockley SW. Safety considerations for the use of blue-light blocking glasses in shift-workers.
J Pineal Res. 2007;42(2): 210-211. [PMID: 17286754]

Lockley SW, Gooley JJ. Circadian photoreception: spotlight on the brain.
Current Biology. 2006 Sep 19;16(18):R795-7. [PMID: 16979545]

Lockley SW, Evans EE, Scheer FA, Brainard GC, Czeisler CA, Aeschbach D. Short-wavelength sensitivity for the direct effects of light on alertness, vigilance, and the waking electroencephalogram in humans.
Sleep. 2006 Feb 1;29(2):161-8. [PMID: 16494083]

Horrocks N, Pounder R, Royal College of Physicians Short-Term Working Group on Medical Nocturnal Shiftwork. Working the night shift: preparation, survival and recovery - a guide for junior doctors.
Clinical Medicine. 2006 Jan-Feb;6(1):61-7. [PMID: 16521358]

Lockley SW. Timed melatonin treatment for delayed sleep phase syndrome: the importance of knowing circadian phase.
Sleep. 2005 Oct 1;28(10):1214-6. [PMID: 16295202]

Rothschild JM, Landrigan CP, Cronin JW, Kaushal R, Lockley SW, Burdick E, Stone PH, Lilly CM, Katz JT, Czeisler CA, Bates DW. The Critical Care Safety Study: The incidence and nature of adverse events and serious medical errors in intensive care.
Crit Care Med. 2005 Aug;33(8):1694-700. [PMID: 16096443]

Landrigan CP, Rothschild JM, Cronin JW, Kaushal R, Burdick E, Katz JT, Lilly CM, Stone PH, Lockley SW, Bates DW, Czeisler CA. Effect of reducing interns' work hours on serious medical errors in intensive care units. 
N Engl J Med. 2004 Oct 28;351(18):1838-48. [PMID: 15509817]

Lockley SW, Cronin JW, Evans EE, Cade BE, Lee CJ, Landrigan CP, Rothschild JM, Katz JT, Lilly CM, Stone PH, Aeschbach D, Czeisler CA; Harvard Work Hours, Health and Safety Group. Effect of reducing interns' weekly work hours on sleep and attentional failures.
N Engl J Med. 2004 Oct 28;351(18):1829-37. [PMID: 15509816]


Hack LM, Lockley SW, Arendt J, Skene DJ. The effects of low-dose 0.5-mg melatonin on the free-running circadian rhythms of blind subjects.
J Biol Rhythms. 2003 Oct;18(5):420-9. [PMID: 14582858]

Lockley SW, Brainard GC, Czeisler CA. High sensitivity of the human circadian melatonin rhythm to resetting by short wavelength light.
J Clin Endocrinol Metab. 2003 Sep;88(9):4502-5. [PMID: 12970330]

Robilliard DL, Archer SN, Arendt J, Lockley SW, Hack LM, English J, Leger D, Smits MG, Williams A, Skene DJ, Von Schantz M. The 3111 Clock gene polymorphism is not associated with sleep and circadian rhythmicity in phenotypically characterized human subjects.
J Sleep Res. 2002 Dec;11(4):305-12. [PMID: 12464098]

Dijk DJ, Lockley SW. Integration of human sleep-wake regulation and circadian rhythmicity.
J Appl Physiol. 2002 Feb;92(2):852-62. Review. [PMID: 11796701] 

Skene DJ, Lockley SW, Arendt J. Use of melatonin in the treatment of phase shift and sleep disorders.
Adv Exp Med Biol. 1999;467:79-84. Review. [PMID: 10721041]

Lockley SW, Skene DJ, James K, Thapan K, Wright J, Arendt J. Melatonin administration can entrain the free-running circadian system of blind subjects.
J Endocrinol. 2000 Jan;164(1):R1-6. [PMID: 10607943]

Lockley SW, Skene DJ, Arendt J. Comparison between subjective and actigraphic measurement of sleep and sleep rhythms.
J Sleep Res. 1999 Sep;8(3):175-83. [PMID: 10476003]

Skene DJ, Lockley SW, James K, Arendt J. Correlation between urinary cortisol and 6-sulphatoxymelatonin rhythms in field studies of blind subjects.
Clin Endocrinol (Oxf). 1999 Jun;50(6):715-9. [PMID: 10468942] 

Lockley SW, Skene DJ, Butler LJ, Arendt J. Sleep and activity rhythms are related to circadian phase in the blind.
Sleep. 1999 Aug 1;22(5):616-23. [PMID: 10450596]

Skene DJ, Lockley SW, Thapan K, Arendt J. Effects of light on human circadian rhythms.
Reprod Nutr Dev. 1999 May-Jun;39(3):295-304. [PMID: 10420432]

Skene DJ, Lockley SW, Arendt J. Melatonin in circadian sleep disorders in the blind.
Biol Signals Recept. 1999 Jan-Apr;8(1-2):90-5. Review. [PMID: 10085469] 

Tabandeh H, Lockley SW, Buttery R, Skene DJ, Defrance R, Arendt J, Bird AC. Disturbance of sleep in blindness.
Am J Ophthalmol. 1998 Nov;126(5):707-12. [PMID: 9822235]

Lockley SW, Skene DJ, Thapan K, English J, Ribeiro D, Haimov I, Hampton S, Middleton B, von Schantz M, Arendt J. Extraocular light exposure does not suppress plasma melatonin in humans.
J Clin Endocrinol Metab. 1998 Sep;83(9):3369-72. [PMID: 9745457]

Arendt J, Skene DJ, Middleton B, Lockley SW, Deacon S. Efficacy of melatonin treatment in jet lag, shift work, and blindness.
J Biol Rhythms. 1997 Dec;12(6):604-17. Review. [PMID: 9406036]


Lockley SW, Skene DJ, Arendt J, Tabandeh H, Bird AC, Defrance R. Relationship between melatonin rhythms and visual loss in the blind.
J Clin Endocrinol Metab. 1997 Nov;82(11):3763-70. [PMID: 9360538]

Lockley SW, Skene DJ, Tabandeh H, Bird AC, Defrance R, Arendt J. Relationship between napping and melatonin in the blind.
J Biol Rhythms. 1997 Feb;12(1):16-25. [PMID: 9104687]

Lockley S, Tabandeh H, Skene D, Buttery R, Bird A, Defrace R, Arendt J. Day-time naps and melatonin in blind people.
Lancet. 1995 Dec 2;346(8988):1491. Erratum in: Lancet 1996 Jan 20;347(8995):206. [PMID: 7491012]