The tissue at the back of the vertebrate eye is the retina, which contains photoreceptors and several other classes of visual cells. The two classes of photoreceptors are rods, for dim light, and cones, for color vision in bright light. It now appears that there is a suppressive effect by the rods on the cone cell responses, depending on the level of dark adaptation of the rods. The mechanisms for these suppressive rod-cone interactions (SCRI) are not clear. This project will combine neurophysiological recording of membrane properties from retinal neurons, and pharmacological probing of the communication at synapses which are the functional contacts for neurochemical transmission between cells. Using the amphibian retina as a model, results will be compared to the features known from psychophysical studies on cone-mediated sensitivity and its interaction with dark adaptation in humans. Results from study of this novel phenomenon are expected to have an impact on visual science in general, on signal processing, and on network neuroscience.
