Sleep and biological daily rhythms (circadian rhythms) are essential to maintaining the healthy balance and functioning of the mind and body. Our master internal circadian clock coordinates our body’s daily physiological and behavioural cycles to the Earth’s solar day (by a process known as entrainment) – including daytime alertness and sleep timing, synchronization of changes in cortisol, growth hormone and organ activity, and fluctuations in mood and cognitive ability.

Disruption of daily sleep and circadian rhythms is commonly experienced by individuals with severe visual impairment. This disruption is often due to a reduction or total loss of light being detected through the eyes to the brain. In humans, our internal circadian rhythms run in cycles slightly longer than 24-hours. These rhythms require daily resetting by external time cues to synchronise our sleep and wake timing to the Earth’s 24-h day and night cycle. External time cues include feeding, activity and exercise, but most importantly, light is the master time cue for resetting our daily rhythms.
Aims of our research studies
The aims of our research study are to examine the impact that sight loss has on sleep and circadian rhythms in the vision impaired community and to assess new methods to more simply diagnose underlying circadian rhythm disruption.
Meet the team

Dr Suzanne Ftouni: Study Coordinator. Researcher at the Sleep and Circadian Neuroscience Institute and Circadian Therapeutics. Specialising in the measurement of human sleep and circadian rhythms

Dr Iona Alexander: Postdoctoral Researcher. Researcher at the Sleep and Circadian Neuroscience Institute and Circadian Therapeutics. Specialising in the measurement of human sleep and circadian rhythms

Professor Russell Foster: Chief Investigator. Head of the Nuffield Laboratory of Ophthalmology, Director of the Sleep and Circadian Neuroscience Institute, University of Oxford

Dr Renata Gomes: Study Investigator. Chief Scientific Officer at the Blind Veterans UK

Professor Susan Downes: Study Investigator. Ophthalmic Surgeon at the Oxford Eye Hospital, specialising in ophthalmic eye disease

Professor Mariya Moosajee: Study Investigator. Consultant Ophthalmologist at Moorfields Eye Hospital and Great Ormond Street Hospital for Children specialising in Genetic Eye Disease.

Professor Maarten De Vos: Study Investigator. Professor of Engineering at KU Leuven University

Ms Ruby Warden: Research technician and recruiter