The retina of the eye is the tissue that contains the photoreceptor cells and a complex network of other nerve cells, or neurons. This network has to work properly over a huge range of light intensity, between the brightest daylight and the darkest night. Recent studies have suggested circadian, or daily, rhythmic changes in many bodily functions, driven by 'biological clocks' that may involve network properties or oscillating biochemical activity in single cells. This study uses the goldfish retina as a model of a complex circuit to explore how changes in chemistry and biochemical factors can regulate the light sensitivity of cells in the retina. Electrophysiological and pharmacological tools will be used to examine how local biochemistry affects circadian activity, in a novel approach using single cells in the retina to test hypotheses about cellular mechanisms for this regulation. Results will extend beyond visual neuroscience to have an impact on understanding regulation of neural circuits in general, and neurochemical modulation in general; better understanding of circadian rhythms could lead to possible future benefits to society including handling circadian aspects of shift-work and jet lag.
