Faculty Profile

Shantha M. W. Rajaratnam, PhD

Lecturer in Medicine (Academic, Part-time), Harvard Medical School
Associate Neuroscientist, Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital

Other Affiliation(s)

School of Psychology, Psychiatry and Psychological Medicine, Monash University, Australia

See publications


Division of Sleep Medicine, Brigham and Women's Hospital
221 Longwood Avenue, BLI-438
Boston, MA 02115

Inter-office Mail Address

BWH Division of Sleep Medicine, BLI-438

Phone 617-732-4013
Fax 617-732-4015

Email swrajaratnam@rics.bwh.harvard.edu

Society Memberships

Associate Fellow and Chartered Psychologist, British Psychological Society
Registered Psychologist, Psychologists Registration Board of Victoria (Australia)
Sleep Research Society
Society for Research on Biological Rhythms
Australian and New Zealand Association of Psychology, Psychiatry and Law

Research Unit(s)

Division of Sleep Medicine, Brigham and Women's Hospital
Harvard Work Hours, Health and Safety Group, Harvard Medical School

Research Interests

Research interests include the role of melatonin in circadian sleep-wake regulation, effects of sleep loss on performance and cognition, shift work, alerting effects of light, legal issues relating to sleepiness and work hours.

Selected Publications

Phipps-Nelson J, Redman JR, Schlangen LJ, Rajaratnam SM. Blue light exposure reduces objective measures of sleepiness during prolonged nighttime performance testing.
Chronobiol Int. 2009 Jul;26(5):891-912. [PMID: 19637049]

Rajaratnam SM, Polymeropoulos MH, Fisher DM, Roth T, Scott C, Birznieks G, Klerman EB. Melatonin agonist tasimelteon (VEC-162) for transient insomnia after sleep-time shift: two randomised controlled multicentre trials.
Lancet. 2009 Feb 7;373(9662):482-91. Epub 2008 Dec 4. Erratum in: Lancet. 2009 Apr 11;373(9671):1252. [PMID: 19054552]

Arendt J, Rajaratnam SM. Melatonin and its agonists: an update.
Br J Psychiatry. 2008 Oct;193(4):267-9. [PMID: 18827285]

Parcell DL, Ponsford JL, Redman JR, Rajaratnam SM. Poor sleep quality and changes in objectively recorded sleep after traumatic brain injury: a preliminary study.
Arch Phys Med Rehabil. 2008 May;89(5):843-50. [PMID: 18452730]

Vandewalle G, Middleton B, Rajaratnam SM, Stone BM, Thorleifsdottir B, Arendt J, Dijk DJ. Robust circadian rhythm in heart rate and its variability: influence of exogenous melatonin and photoperiod.
J Sleep Res. 2007 Jun;16(2):148-55. [PMID: 17542944]

Swann CE, Yelland GW, Redman JR, Rajaratnam SM. Chronic partial sleep loss increases the facilitatory role of a masked prime in a word recognition task.
J Sleep Res. 2006 Mar: 15(1):23-9. [PMID: 16489999]

Parcell DL, Ponsford JL, Rajaratnam SM, Redman JR. Self-reported changes to nighttime sleep after traumatic brain injury.
Arch Phys Med Rehabil. 2006 Feb; 87(2):278-85. [PMID: 16442985]

Steele DL, Rajaratnam SM, Redman JR, Ponsford JL. The effect of traumatic brain injury on the timing of sleep.
Chronobiol Int. 2005; 22(1):89-105. [PMID: 15865324]

Rajaratnam SM, Jones CB. Lessons about sleepiness and driving from the Selby rail disaster case: R v Gary Neil Hart.
Chronobiol Int. 2004; 21(6):1073-7. [PMID: 15646252]

Lenne MG, Dwyer F, Triggs TJ, Rajaratnam S, Redman JR. The effects of a nap opportunity in quiet and noisy environments on driving performance.
Chronobiol Int. 2004; 21(6):991-1001. [PMID: 15646244]

Rajaratnam SM, Middleton B, Stone BM, Arendt J, Dijk DJ. Melatonin advances the circadian timing of EEG sleep and directly facilitates sleep without altering its duration in extended sleep opportunities in humans.
J Physiol. 2004 Nov 15;561(Pt 1):339-51. Epub 2004 Sep 30. [PMID: 15459246]

Phipps-Nelson J, Redman JR, Dijk DJ, Rajaratnam SM. Daytime exposure to bright light, as compared to dim light, decreases sleepiness and improves psychomotor vigilance performance.
Sleep. 2003 Sep;26(6):695-700. [PMID: 14572122]

Rajaratnam SM. Legal issues in accidents caused by sleepiness.
J Hum Ergol (Tokyo). 2001 Dec;30(1-2):107-11. [PMID: 14564867]

Rajaratnam SM, Dijk DJ, Middleton B, Stone BM, Arendt J. Melatonin phase-shifts human circadian rhythms with no evidence of changes in the duration of endogenous melatonin secretion or the 24-hour production of reproductive hormones.
J Clin Endocrinol Metab. 2003 Sep;88(9):4303-9. Erratum in: J Clin Endocrinol Metab. 2004 Jun; 89(6):2997. [PMID: 12970302]

Rajaratnam SM, Redman JR. Circadian locomotor activity rhythms of the diurnal Indian palm squirrel in constant light.
Chronobiol Int. 2001 Jan; 18(1):47-60. [PMID: 11247113]

Rajaratnam SM, Redman JR. Social contact synchronizes free-running activity rhythms of diurnal palm squirrels.
Physiol Behav. 1999 Mar; 66(1):21-6. [PMID: 10222468]

Rajaratnam SM, Redman JR. Entrainment of activity rhythms to temperature cycles in diurnal palm squirrels.
Physiol Behav. 1998 Jan;63(2):271-7. [PMID: 9423969]

Rajaratnam SM, Redman JR. Effects of daily melatonin administration on circadian activity rhythms in the diurnal Indian palm squirrel (Funambulus pennanti).
J Biol Rhythms. 1997 Aug;12(4):339-47. [PMID: 9438882]


Barger LK, Lockley SW, Rajaratnam SM, Landrigan CP. Neurobehavioral, health, and safety consequences associated with shift work in safety-sensitive professions.
Curr Neurol Neurosci Rep. 2009 Mar;9(2):155-64. Review. [PMID: 19268039]

Jones CB, Dorrian J, Rajaratnam SM. Fatigue and the criminal law.
Ind Health. 2005 Jan; 43(1):63-70. Review. [PMID: 15732306]

Rajaratnam SM, Arendt J. Health in a 24-h society.
Lancet. 2001 Sep 22; 358(9286):999-1005. Review. [PMID: 11583769]

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