Psychology 1000 Lecture Notes - Lecture 3: Rhodopsin, Stapes, Visual Phototransduction

• School: Western University
• Department: Psychology
• Course: Psychology 1000
• Professor: Dr.Mike

Document Summary

A photoreceptor is a specialized nerve that can take light and convert to neural impulse. Inside rod are optic discs, which are large membrane bound structures thousands of them. In membrane of each optic disc are proteins that fire aps to the brain. Cones are also specialized nerves with same internal structure as rod. Rods contain rhodopsin, cones have similar protein photopsin. If light hits a rhodopsin, will trigger the phototransduction cascade. Differences: 120 m rods vs. 6 million cones, cones are concentrated in the fovea, rods are 1000x more sensitive to light than cones. Better at detecting light telling us whether light is present, ie. bw vision: cones are less sensitive but detect color (60% red, 30% green, 10% blue, rods have slow recovery time, cones have fast recovery time. Takes a while to adjust to dark rods need to be reactivated. Where optic nerve connects to retina, blind spot no cones or rods.