Prof Shanthakumar Wilson Rajaratnam - Researcher Profile

Shanthakumar Wilson Rajaratnam

Address

School of Psychology and Psychiatry
Building 17

Contact Details

Tel: +61 3 990 53934

Email: Shantha.Rajaratnam@monash.edu


Biography

Sleep is increasingly recognised as the third pillar of good health, along side diet and exercise. Poor sleep quality and sleep deficiency are linked to a number of serious health problems, including depression and cardiovascular disease, as well as impaired alertness and neurocognitive functioning, reduced productivity and increased accident risk.

Our research program aims to investigate the role of the internal biological clock in the regulation of the sleep-wake cycle, and how disruption of the clock leads to sleep disorders and other physiological consequences (for example, in shift workers). We are developing novel treatment approaches for sleep disorders that are caused by biological clock disruption. These include light and melatonin treatments. We are also investigating the contribution of sleep disturbances and fatigue to mood disorders and impaired cognition in clinical populations.

Sleep loss and impaired alertness adversely affect occupational safety, health and productivity, and also road safety. About 20 percent of serious car crash injuries are associated with driver sleepiness. Our research is examining innovative technologies to monitor alertness in occupational and transportations settings, and is developing and testing intervention strategies aimed at reducing the burden associated with impaired alertness in these contexts.

Related Links:

Research & Supervision Interests

    • Circadian regulation of sleep and wakefulness
    • Effects of melatonin and melatonin agonists on sleep and circadian rhythms
    • Effects of light on the human circadian system
    • Consequences of sleep loss and sleep disruption in neuropsychiatric disorders
    • Development of interventions for sleep loss and sleepiness in transport and occupational settings
    • Legal issues relating to sleep loss and sleepiness

Keywords

Circadian rhythms, Insomnia, Light, Melatonin, Shift work, Sleep, Sleep disorders, Sleep loss, Sleepiness-related crashes

Qualifications

LLB(HONS)
Institution: Monash University
Year awarded: 2000
PHD
Institution: Monash University
Year awarded: 1998
BSC(HONS)
Institution: Monash University
Year awarded: 1994

Publications

Book Chapters

Ftouni, S., Sletten, T., Barger, L., Lockley, S., Wilson Rajaratnam, S., 2012, Shift Worker Disorder, in Therapy in Sleep Medicine, eds TJ Barkoukis, JK Matheson, R Ferber, K Doghramji, Elsevier, US, pp. 378-389.

Wilson Rajaratnam, S., Jones, C., Lee, C., 2010, Sleep, law, and policy, in Sleep, Health, and Society: From aetiology to public health, eds Francesco P. Cappuccio, Michelle A. Miller and Steven W. Lockley, Oxford University Press, Oxford, UK, pp. 417-434.

Journal Articles

Ftouni, S., Sletten, T.L., Howard, M., Anderson, C., Lenne, M.G., Lockley, S.W., Wilson Rajaratnam, S.M., 2013, Objective and subjective measures of sleepiness, and their associations with on-road driving events in shift workers, Journal of Sleep Research [E], vol 22, issue 1, Wiley-Blackwell Publishing Ltd, United Kingdom, pp. 59-69.

Hassed, C.S., Antoniades, J., Jones, K.M., Wilson Rajaratnam, S.M., Kiropoulos, L.A., Naughton, M.T., Piterman, L., 2012, An examination of australian general practitioners' knowledge, attitudes and practices in relation to sleep disorders, Malaysian Family Physician [P], vol 7, issue 1, Academy of Family Physicians of Malysia, Malaysia, pp. 16-23.

Hassed, C.S., Antoniades, J., Jones, K.M., Wilson Rajaratnam, S.M., Kiropolous, L., Naughton, M.T., Piterman, L., 2012, An examination of australian general practitioners' knowledge, attitudes and practices in relation to sleep disorders, Malaysian Family Physician [P], vol 7, issue 1, 1985-207X, Malaysia, pp. 16-23.

Ogeil, R.P., Wilson Rajaratnam, S.M., Broadbear, J.H., 2012, Disturbed sleep in ecstasy users reported by partners/roommates, Australian and New Zealand Journal of Psychiatry [E], vol 46, issue 6, Sage Publications Ltd., Australia, pp. 587-588.

Ogeil, R.P., Wilson Rajaratnam, S.M., Broadbear, J.H., 2012, Ecstasy and sleep disturbance: progress towards elucidating a role for the circadian system, Sleep and Biological Rhythm [P], vol 10, issue 1, Wiley-Blackwell Publishing Asia, Australia, pp. 3-13.

Ponsford, J.L., Ziino, C.V., Parcell, D.L., Shekleton, J., Roper, M., Redman, J.R., Phipps-Nelson, B., Wilson Rajaratnam, S.M., 2012, Fatigue and sleep disturbance following traumatic brain injury - their nature, causes and potential treatments, Journal Of Head Trauma Rehabilitation [P], vol 27, issue 3, Lippincott Williams & Wilkins, United States, pp. 224-233.

Ogeil, R.P., Kennaway, D.J., Salkeld, M.D., Wilson Rajaratnam, S.M., Broadbear, J.H., 2012, MDMA induces Per1, Per2 and c-fos gene expression in rat suprachiasmatic nuclei, Psychopharmacology [P], vol 220, issue 4, Springer, Germany, pp. 835-843.

Barger, L., Ogeil, R.P., Drake, C.L., O'Brien, C.B., Ng, K.T., Wilson Rajaratnam, S.M., 2012, Validation of a questionnaire to screen for shift work disorder, Sleep [E], vol 35, issue 12, Associated Professional Sleep Societies Llc, United States, pp. 1693-1703.

Ponsford, J.L., Ziino, C.V., Parcell, D.L., Shekleton, J.A., Roper, M., Redman, J.R., Phipps-Nelson, B., Wilson Rajaratnam, S.M., 2012, igue and sleep disturbance following traumatic brain injury-their nature, causes, and potential treatments, Journal Of Head Trauma Rehabilitation [P], vol 27, issue 3, Lippincott Williams & Wilkins, USA, pp. 224-233.

Yeung, W., Sletten, T., Wilson Rajaratnam, S., 2011, A phase-advanced, extended sleep paradigm to increase sleep duration among early-morning shift workers: A preliminary investigation, Scandinavian Journal of Work, Environment and Health [P], vol 37, issue 1, Tyoterveyslaitos, Finland, pp. 62-69.

Ogeil, R., Wilson Rajaratnam, S., Broadbear, J., 2011, Assessing sleep disturbance in ecstasy users: A questionnaire study, The Open Addiction Journal [E], vol 4, issue special issue, Bentham Open, Netherlands, pp. 32-33.

Ogeil, R., Wilson Rajaratnam, S., Phillips, J., Redman, J., Broadbear, J., 2011, Ecstasy use and self-reported disturbances in sleep, Human Psychopharmacology-Clinical And Experimental [P], vol 26, issue 7, John Wiley & Sons Ltd, UK, pp. 508-516.

Gooley, J., Chamberlain, K., Smith, K., Khalsa, S., Wilson Rajaratnam, S., Van Reen, E., Zeitzer, J., Czeisler, C., Lockley, S., 2011, Exposure to room light before bedtime surpresses melatonin onset and shortens melatonin duration in humans, Journal of Clinical Endocrinology and Metabolism [P], vol 96, issue 3, The Endocrine Society, United States, pp. E463-E472.

Kevat, D., Davies, A., Cameron, P., Wilson Rajaratnam, S., 2011, Letters: Increased mortality associated with after-hours and the weekend admission to the intensive care unit: a retrospective analysis, Medical Journal Of Australia [P], vol 194, issue 11, Australasian Medical Publishing Company Pty. Ltd., Australia, p. 616.

Wilson Rajaratnam, S., Barger, L., Lockley, S., Shea, S., Wang, W., Landrigan, C., O'Brien, C., Qadri, S., Sullivan, J.P., Cade, B., Epstein, L., White, D., Czeisler, C., 2011, Sleep disorders, health, and safety in police officers, Jama-Journal Of The American Medical Association [P], vol 306, issue 23, American Medical Association, USA, pp. 2567-2578.

Ogeil, R., Rajaratnam, S.M.W., Redman, J., Broadbear, J., 2010, Acute MDMA administration alters the distribution and circadian rhythm of wheel running activity in the rat, Brain Research [P], vol 1359, issue C, Elsevier BV, Netherlands, pp. 128-136.

Jones, C., Wilson Rajaratnam, S., Dorrian, J., Dawson, D., 2010, Lay perceptions of responsibility and accountability for fatigue-related road crashes, Journal of the Australasian College of Road Safety [P], vol 21, issue 1, Australasian College of Road Safety, Australia, pp. 30-35.

Ferguson, S., Wilson Rajaratnam, S., Dawson, D., 2010, Melatonin agonists and insomnia, Expert Review of Neurotherapeutics [P], vol 10, issue 2, Expert Reviews Ltd, UK, pp. 305-318.

Cohen, D.A., Wang, W., Klerman, E.B., Rajaratnam, S.M.W., 2010, Ramelteon prior to a short evening nap impairs neurobehavioral performance for up to 12 hours after awakening, Journal of Clinical Sleep Medicine [P], vol 6, issue 6, The American Academy of Sleep Medicine, USA, pp. 565-571.

Shekleton, J., Rogers, N., Wilson Rajaratnam, S., 2010, Searching for the daytime impairments of primary insomnia, Sleep Medicine Reviews [P], vol 14, issue 1, Elsevier Masson, France, pp. 47-60.

Shekleton, J., Parcell, D., Redman, J.R., Phipps-Nelson, J., Wilson Rajaratnam, S., Ponsford, J., 2010, Sleep disturbance and melatonin levels following traumatic brain injury, Neurology [P], vol 74, issue 21, Lippincott Williams & Wilkins, USA, pp. 1732-1738.

Gooley, J., Wilson Rajaratnam, S., Brainard, G., Kronauer, R., Czeisler, C., Lockley, S., 2010, Spectral responses of the human circadian system depend on the irradiance and duration of exposure to light, Science Translational Medicine [P], vol 2, issue 31 (Art. No: 31ra33), American Association for the Advancement of Science, USA, pp. 1-9.

Phipps-Nelson, B., Redman, J., Rajaratnam, S.M.W., 2010, Temporal profile of prolonged, night-time driving performance: Breaks from driving temporarily reduce time-on-task fatigue but not sleepiness, Journal of Sleep Research [E], vol 20, issue 3, Wiley-Blackwell Publishing Ltd, UK, pp. 404-415.

Sletten, T., Vincenzi, S., Redman, J., Lockley, S., Wilson Rajaratnam, S.M., 2010, Timing of sleep and its relationship with the endogenous melatonin rhythm, Frontiers in Neurology [E], vol E, issue Art. No: 137, Frontiers Research Foundation, Switzerland, pp. 1-8.

Phipps-Nelson, B., Redman, J.R., Schlangen, L.J., Wilson Rajaratnam, S.M., 2009, Blue light exposure reduces objective measures of sleepiness during prolonged nighttime performance testing, Chronobiology International [P], vol 26, issue 5, Informa Healthcare, UK, pp. 891-912.

Rajaratnam, S., Polymeropoulos, M.H., Fisher, D.M., Roth, T., Scott, C., Birznieks, G., Klerman, E.B., 2009, Melatonin agonist tasimelteon (VEC-162) for transient insomnia after sleep-time shift: Two randomised controlled multicentre trials, The Lancet, vol 373, The Lancet Publishing Group, UK, pp. 482-491.

Wilson Rajaratnam, S.M., Cohen, D., Rogers, N.L., 2009, Melatonin and melatonin analogues, Sleep Medicine Clinics [P], vol 4, issue 2, WB Saunders Co., USA, pp. 179-193.

Barger, L., Lockley, S.W., Wilson Rajaratnam, S.M., Landrigan, C.P., 2009, Neurobehavioral, health, and safety consequences associated with shift work in safety-sensitive professions, Sleep [P], vol 9, issue 2, The American Academy of Sleep Medicine, USA, pp. 155-164.

Other

Antoniades, J., Jones, K., Hassed, C., Wilson Rajaratnam, S., Naughton, M., Kiropoulos, L., Piterman, L., 2012, The Sleep Study, Monash University, Australia.

Teaching Commitment

2011-present Director of Undergraduate Programs, School of Psychology and Psychiatry

Community Service

2011-present President, Australasian Sleep Association

http://www.sleep.org.au/

 

Grants

Title:
A 12-week, randomised, double-blind, placebo-controlled, parallel-group study to evaluate the efficacy and safety of CEP-10953 (150 mg) as treatment for adults with residual excessive sleepiness.
Investigators:
Wilson Rajaratnam, S, Redman, J, Kulkarni, J
Funding:
(2005 - 2009). Covance Pty Ltd.
Title:
A Comparative Study of Circadian Rhythms in Long-Evans Rats (Rattus Norvegicus), Israeli Sand Rats (Psammomys Obesus) and Indian Palm Squirrels (Funambulus Pennanti).
Investigators:
Redman, J, Wilson Rajaratnam, S, Horne, M
Funding:
(1999 - 1999). Australian Research Council (ARC).
Title:
A randomised controlled trial of melatonin to increase sleep duration in early shiftworkers.
Investigators:
Wilson Rajaratnam, S
Funding:
(2009 - 2013). Australasian Sleep Trials Network.
Title:
Acute alerting effects of daytime exposure to specific wavelengths of light.
Investigators:
Wilson Rajaratnam, S, Redman, J, Lockley, S
Funding:
(2007 - 2011). National Health & Medical Research Council (NHMRC).
Title:
Assessment of Circadian Phase for the Diagnosis and Treatment of Sleep Phase Insomnia.
Investigators:
Wilson Rajaratnam, S
Funding:
(2010 - 2014). The Brigham and Women's Hospital, Inc., USA.
Title:
Attentional Mechanisms in the Relationship Between Sleep Disruption and Academic Outcomes in Australian School Children.
Investigators:
Cornish, K, Wilson Rajaratnam, S, Rinehart, N, Conduit, R, Heussler, H, Hiscock, H
Funding:
(2012 - 2016). Australian Research Council (ARC).
Title:
Australia - Harvard Fellowship: Steven Lockley.
Investigators:
Lockley, S, Wilson Rajaratnam, S
Funding:
(2009 - 2013). Harvard Club of Australia Foundation.
Title:
Australia-Harvard Fellowship.
Investigators:
Wilson Rajaratnam, S, Barger, L
Funding:
(2012 - 2016). Harvard Club of Australia Foundation.
Title:
Circadian phase assessment in chronic insomnia and major depression.
Investigators:
Wilson Rajaratnam, S, Rogers, N, Kulkarni, J
Funding:
(2007 - 2011). Vanda Pharmaceuticals - USA.
(2007 - 2012). Vanda Pharmaceuticals - USA.
Title:
Developing a case for a National Fatigue Risk Management Standard.
Investigators:
Wilson Rajaratnam, S
Funding:
(2010 - 2014). CRC for Rail Innovation.
Title:
Developing the Field of Chronobiology in India and Australia.
Investigators:
Wilson Rajaratnam, S
Funding:
(2009 - 2013). Department of Foreign Affairs and Trade.
Title:
Development of an intervention plan to increase detection, diagnosis and appropriate management of sleep disorders in the Australian primary care setting.
Investigators:
Wilson Rajaratnam, S, Piterman, L, Naughton, M, Hassed, C, Kiropoulos, L
Funding:
(2008 - 2012). Philips Respironics.
Title:
Development of an intervention plan to increase detection, diagnosis and appropriate management of sleep disorders n the Australian primary care setting.
Investigators:
Wilson Rajaratnam, S, Piterman, L, Hassed, C, Kiropoulos, L, Naughton, M
Funding:
(2009 - 2013). ResMed Foundation.
Title:
Effects of Melatonin Administration on Sleep-wakefulness in the Palm Squirrel.
Investigators:
Wilson Rajaratnam, S
Funding:
(1999 - 2003). Australian Academy of Science.
Title:
Effects of Melatonin on Skeep-wakefulness in the Diurnal Indian Palm Squirrel.
Investigators:
Wilson Rajaratnam, S
Funding:
(1999 - 1999). Clive & Vera Ramaciotti Foundation.
Title:
Effects of short wavelength light on mental alertness and driving simulator performance.
Investigators:
Wilson Rajaratnam, S, Redman, J, Dijk, D, Conduit, R, Phipps-Nelson, B
Funding:
(2003 - 2007). Philips Lighting.
Title:
Efficacy of light therapy for sleepiness and fatigue following traumatic brain injury.
Investigators:
Ponsford, J, Wilson Rajaratnam, S, Lockley, S
Funding:
(2011 - 2015). Victorian Neurotrauma Initiative.
Title:
Efficacy of melatonin for sleep disturbance following traumatic brain injury.
Investigators:
Ponsford, J, Wilson Rajaratnam, S
Funding:
(2012 - 2016). National Health & Medical Research Council (NHMRC).
Title:
Enhancing the sleep/wake/work database that underpins fatigue-modelling algorithms.
Investigators:
Wilson Rajaratnam, S
Funding:
(2010 - 2014). CRC for Rail Innovation.
Title:
Evaluation of SmartCap technology to monitor drowsiness in healthy volunteers exposed to sleep restriction.
Investigators:
Wilson Rajaratnam, S, Sletten, T
Funding:
(2011 - 2015). EdanSafe Pty Ltd.
Title:
Fatigue, attention and sleep disturbance after traumatic brain injury.
Investigators:
Ponsford, J, Redman, J, Wilson Rajaratnam, S, O'Sullivan, R
Funding:
(2005 - 2009). National Health & Medical Research Council (NHMRC).
Title:
Non-24-Hour Sleep-Wake Disorder Screening Questionnaire: Development and Validation in a Patient Population.
Investigators:
Wilson Rajaratnam, S
Funding:
(2011 - 2015). Vanda Pharmaceuticals - USA.
Title:
Randomised Controlled Trial of Melatonin for Delayed Sleep Phase Disorder.
Investigators:
Wilson Rajaratnam, S, Lack, L, Grunstein, R, Lockley, S, Kennaway, D
Funding:
(2012 - 2016). National Health & Medical Research Council (NHMRC).
Title:
Randomised controlled trial of a light intervention to enhance alertness and performance in night shiftworkers.
Investigators:
Wilson Rajaratnam, S, Rogers, N, Ferguson, S, Lockley, S, Kennaway, D
Funding:
(2009 - 2012). National Health & Medical Research Council (NHMRC).
Title:
Randomised controlled trial of a light intervention to enhance alertness and performance in night shiftworkers: SUBSTUDY.
Investigators:
Wilson Rajaratnam, S, Sletten, T
Funding:
(2010 - 2014). Philips Respironics.
Title:
Randomized, double-blind, placebo-controlled, single-centre stujdy ofthe effects of VEC162 on circadian rhythm in healthy subjects.
Investigators:
Wilson Rajaratnam, S
Funding:
(2004 - 2008). Vanda Pharmaceuticals - USA.
Title:
Shift Work Disorder (SWD) Screening Questionnaire: Validation in Clinically Diagnosed and Population-Based Samples.
Investigators:
Wilson Rajaratnam, S, Ng, K, Ogeil, R
Funding:
(2010 - 2014). The Brigham and Women's Hospital, Inc., USA.
Title:
The Cambridge Neuropsychological Test Automated Battery (CANTAB).
Investigators:
Wilson Rajaratnam, S, Horne, R, Lenne, M, Hamilton, G, Stout, J, Sletten, T, Naughton, M
Funding:
(2009 - 2013). National Health & Medical Research Council (NHMRC).
Title:
The SenseWear PRO3 Armband and ancillary equipment.
Investigators:
Hamilton, G, O'Driscoll, D, Strauss, B, Wilson Rajaratnam, S
Funding:
(2009 - 2014). National Health & Medical Research Council (NHMRC).

Postgraduate Research Supervisions

Current Supervision

Program of Study:
(DOCTORATE BY RESEARCH).
Thesis Title:
A randomised controlled trial of cognitive behavioural therapy for insomnia (CBT-I) in co-morbid insomnia and depression..
Supervisors:
Rajaratnam, S (Main), Sletten, T (Associate).
Program of Study:
(DOCTORATE BY RESEARCH).
Thesis Title:
Efficacy of melatonin for sleep disturbance following traumatic brain injury.
Supervisors:
Ponsford, J (Joint-co), Rajaratnam, S (Joint).
Program of Study:
(DOCTORATE BY RESEARCH).
Thesis Title:
Relationship between sleep deficiency and poor behavior in children with autism.
Supervisors:
Cornish, K (Main), Conduit, R (Associate), Rajaratnam, S (Associate).
Program of Study:
(DOCTORATE BY RESEARCH).
Thesis Title:
Sleepiness and neurobehavioural impairments in shiftworkers.
Supervisors:
Rajaratnam, S (Main), Sletten, T (Associate).
Program of Study:
(DOCTORATE BY RESEARCH).
Thesis Title:
The effect of time of day and consecutive night shifts on medical error in the ICU environment.
Supervisors:
Cameron, P (Joint-co), Rajaratnam, S (Joint).
Program of Study:
(DOCTORATE BY RESEARCH).
Thesis Title:
Traumatic Brain Injury and Psychiatric Disorder.
Supervisors:
Ponsford, J (Main), Mckay, A (Associate), Rajaratnam, S (Associate).
Program of Study:
(DOCTORATE BY RESEARCH).
Thesis Title:
Work hours, sleep and sleep disorders in relation to mining health, safety and productivity.
Supervisors:
Rajaratnam, S (Main), Anderson, C (Associate).

Completed Supervision

Student:
Ogeil, R.
Program of Study:
MDMA: effects on sleep and the circadian system. (PHD) 2011.
Supervisors:
Broadbear, J (Main), Rajaratnam, S (Associate).
Student:
Parcell, D.
Program of Study:
SLEEP DISTURBANCE FOLLOWING TRAUMATIC BRAIN INJURY. (PHD) 2004.
Supervisors:
Ponsford, J (Main), Rajaratnam, S (Associate), Redman, J (Associate).
Student:
Phipps-Nelson, B.
Program of Study:
The temporal profile of prolonged nocturnal driving: counteracting sleepiness and fatigue with blue light and breaks. (PHD) 2011.
Supervisors:
Rajaratnam, S (Main), Redman, J (Associate).
Student:
Shekleton, J.
Program of Study:
Neurobehavioural performance in primary insomnia and healthy individuals: role of circadian rhythms, prior sleep and psychological well-being. (PHD) 2011.
Supervisors:
Rajaratnam, S (Main).
Student:
Sinclair, K.
Program of Study:
Fatigue and sleep disturbance following traumatic brain injury: a role for light therapy?. (PHD) 2012.
Supervisors:
Rajaratnam, S (Main), Ponsford, J (Associate).