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Summer Science Exhibition 2008

Why do we blink?









The Royal Society, London, 6-9 Carlton House Terrace, London, SW1Y 5AG


Tearscope image.

Cardiff University; Science & Technology Facilities Council

Blinking is something you rarely think about but is essential to keeping our eyes healthy. Each blink bathes the eyes in warm tears that remain on the surface of the eye as a tear film, preventing injury, regulating sensory input from the eye to the brain and providing, nutrition, comfort and clear vision. So what causes us to blink? Research at Cardiff University is testing a theory based on the temperature of tears.

‘The theory is that as the tear film evaporates from the surface of the eye, the eye gets cooler and this is what triggers the blink,’ explains Christine Purslow of the School of Optometry, Cardiff. ‘If we can determine what causes us to blink, then we could stimulate this natural process in those who suffer from dry eyes.’

Not all individuals blink as much as others and some conditions like Parkinson’s reduce the blink rate. Humans are therefore being studied to see what it is about their tear film that relates to their blinking pattern. There are also differences between different species. ‘Rabbits would definitely win a staring contest,’ says Christine. ‘They hardly ever blink, we think, due to differing properties of their anterior eye and tear film.’

At our Royal Society exhibit you will find out why we all blink at different rates – take part in a survey about blinking which will help us find out more about this topic. You will need a friend to record your blink rate in order to take part

Exhibitors' website - find out more about who we are and what our research is about:

Contact the exhibitors:
Why do we blink? The Royal Society, London 6-9 Carlton House Terrace London SW1Y 5AG UK