Optometry academics attend International Pupil Colloquium
Professor Ron Douglas reflects on the recent International Pupil Colloquium held in Oxford
In Greek mythology Iris was the messenger of the Gods. She was the daughter of Thaumas, the God of wonder, and Electra, a sea nymph. The union of water and wonder is of course a rainbow, reflecting the multiple colours of the human iris which form the eye’s pupil. The pupil is of course also how light, the message from the Gods, enters the eye.
Given the pupil’s exotic mythical past, it is disappointing that in some ways it is the body’s least glamorous structure. How interesting can a hole really be? However, without it our vision would be much worse, as it not only controls the amount of light entering the eye, it also determines the quality of the image seen.
Furthermore, monitoring its response to various stimuli is of immense clinical importance. It is after all one of the ways of determining if someone is dead! Perhaps more usefully it is also a central component of most neurological examinations and, for example, helps pinpoint the location of intra-cranial tumours and aneurysms.
Consequently, every two years basic scientists and clinicians from around the world with an interest in the pupil gather for the International Pupil Colloquium. Two years ago the meeting was in Alabama. This year’s 31st meeting was hosted for three days in mid-September by Pembroke College in Oxford, birthplace of the Hobbit and Lord of the Rings.
Perhaps surprisingly, given the meeting’s location, Optometry’s Applied Vision Research Centre had a significant role to play. Professor John Barbur and Dr Hannah Gillespie-Gallery (a recent PhD graduate) were half of the organising committee. John was also a speaker at the meeting, as were Professor Chris Tyler and myself.
The meeting was attended by 62 delegates from 12 countries including Australia, Canada, Romania, Saudi Arabia, and the USA. The largest delegation, however, was from Japan, with 13 participants. This is in part explained by the strength of Japanese pupil research. However, the meeting was also very generously supported by the Japan Society for the Promotion of Science (JSPS). They sponsored the full costs of four scientists to attend the meeting and also contributed significantly to the running costs of the meeting. This association with the JSPS was a direct result of a JSPS sponsored visit by Professor Barbur to a dozen research institutions in Japan in 2014. A good example of the School of Health Sciences internationalisation activities.
A centre-piece of the meeting was the Loewenfeld lecture which honours one of the field’s most eminent figures, Irene Loewenfeld's, and is given by someone who has contributed significantly to pupil research in recent years.
The 2nd Lowenfeld lecture was in fact given by our own Professor Barbur in 2001. This year it was delivered by Professor Russell Foster, FRS, CBE, head of the Nuffield Laboratory of Ophthalmology and the Sleep and Circadian Neuroscience Institute in Oxford. It highlighted the importance of a recently discovered 3rd photoreceptor type in the mammalian retina in the pupil response. These melanopsin-containing photoreceptors, which represent one of the major discoveries in the field of vision research in the last 50 years, formed a large part of the meeting and were the subject of 18 of the 50 presented papers.
Although the majority of the meeting revolved around the human pupil response, the meeting ended with four papers on the odd shaped pupils of some animals. Delegates thus learned why the cat’s pupil is a vertical slit, while the pupil of sheep is elongated horizontally and the colour blind cuttlefish even has a pupil shaped like a W.
The talks were highly stimulating and although no definite answers emerged to account for the variety of optics and pupil geometries in different species, the recent progress made in understanding the function of the pupil response to light in humans and others animals and the properties of the mechanisms involved has been significant. The delegates were assured that much remains to be done to unravel the secrets of the pupil which guarantees many more pupil symposia in years to come.
Ron Douglas is a Professor in the Division of Optometry and Visual Science. His research covers mammalian pupillometry and ocular adaptations in lower vertebrates. You can also visit the Colloquium website for a full list of abstracts.