Daylight vision beyond cone photoreceptors

The ability of cones to detect small differences in light intensity over fine spatiotemporal scales is the basis of high acuity vision. However, high amplitude and coarse patterns are common in visual scenes. An ‘intelligent designer’ may thus include a separate photoreceptor optimised for detecting such features. Our latest data leads to the striking conclusion that such a function is indeed provided by the inner retinal photopigment, melanopsin. I present an inventive and original programme of work to test this hypothesis, built upon my laboratory’s world-leading technological expertise in multi-primary visual display design (allowing us to produce images visible to melanopsin for the first time), and its multi-disciplinary infrastructure spanning molecular biology and cell culture to electrophysiology and behaviour. I will employ new and existing transgenic mouse lines and our colony of Rhabdomys, a diurnal mouse with strong cone vision. I will define melanopsin’s contribution to vision in healthy animals with fully intact visual systems, and in mouse models of photoreceptor degeneration. I will determine whether enhancing melanopsin’s activity in retinal degeneration can augment residual vision. My project holds the promise of a step-change in our understanding of daytime vision with wide-ranging practical applications.