Dr Nayantara Santhi

Researcher

Associate Professor in the School of Psychology at Northumbria University. Research spans non-visual effects of light, circadian timing and temperature as zeitgebers, insomnia interventions, and sleep in microgravity. Previously at Surrey Sleep Research Centre and Harvard Medical School.

Scholar ORCID

Biography

I am an Associate Professor in the School of Psychology at Northumbria University, with a research career spanning the Surrey Sleep Research Centre and Harvard Medical School’s Division of Sleep Medicine. My work sits at the intersection of chronobiology, sleep science, and individual differences, with a focus on how circadian timing and sleep are regulated across diverse populations. I am particularly interested in the non-visual effects of light, the role of temperature and behaviour as circadian timing cues, and the interaction between sleep homeostasis and the circadian clock in shaping cognition and mood.

My current projects include work on light sensitivity in bipolar disorder (HELIOS-BD), sleep and circadian disruption in microgravity environments, insomnia interventions, and circadian regulation in people with visual impairments. I also contribute to international efforts to standardise light exposure research, including the ENLIGHT reporting checklist and wearable light dosimetry metadata standards.

Education

PhD in Psychology - August 2000

Experience

Associate Professor - School of Psychology, Northumbria University (Newcastle upon Tyne, UK | Current)

Researcher - Surrey Sleep Research Centre, University of Surrey (UK)

Researcher - Division of Sleep Medicine, Brigham and Women’s Hospital / Harvard Medical School (Boston, USA)

Selected Publications

Lázár, A.S., Lazar, Z.I., Santhi, N., et al. (2025). Circadian and Sleep-Wake Modulation of Functional Connectivity Across Brain Oscillations and States Linked to Cognition in Humans. Preprint.

Ball, D.M., Mann, S.S., Santhi, N., et al. (2025). Temperature as a circadian timing cue in the visually impaired. Progress in Brain Research, 292.

Elder, G., Santhi, N., Robson, A., et al. (2024). An online behavioural self-help intervention rapidly improves acute insomnia severity and subjective mood during the COVID-19 pandemic. Sleep, 47(6).

Bonmatí-Carrión, M.Á., Santhi, N., Atzori, G., et al. (2024). Effect of 60 days of head down tilt bed rest on amplitude and phase of rhythms in physiology and sleep in men. npj Microgravity, 10, 42.

Spitschan, M., Hammad, G., Blume, C., Santhi, N., et al. (2024). Metadata recommendations for light logging and dosimetry datasets. BMC Digital Health.

Roguski, A., Needham, N., MacGillivray, T., Santhi, N., et al. (2024). Investigating light sensitivity in bipolar disorder (HELIOS-BD). Wellcome Open Research.

Spitschan, M., Kervezee, L., Lok, R., Santhi, N., et al. (2023). ENLIGHT: A consensus checklist for reporting laboratory-based studies on the non-visual effects of light in humans. EBioMedicine.

Polasek, D., Santhi, N., Alfonso-Miller, P., et al. (2023). Nutritional interventions in treating menopause-related sleep disturbances: a systematic review. Nutrition Reviews.

Groeger, J.A., Lo, J.C., Santhi, N., Lazar, A.S., Dijk, D.J. (2022). Contrasting Effects of Sleep Restriction, Total Sleep Deprivation, and Sleep Timing on Positive and Negative Affect. Frontiers in Behavioral Neuroscience.