PSYA01H3 Chapter Notes - Chapter 4: Receptive Field, Peripheral Vision, Visual Acuity
Document Summary
The retina is the interface between the world of light outside the body and the world of vision inside the central nervous system. Two types of photoreceptor cells in the retina contain light-sensitive pigments that transduce light into neural impulses. Cones detect color, operate under normal daylight conditions, and allow us to focus on fine detail. Rods become active under low-light conditions for night vision (see figure 4. 6) Rods are much more sensitive photoreceptors than cones, but this sensitivity comes at a cost. Because all rods contain the same photopigment, they provide no information about color and sense only shades of gray. Think about this the next time you wake up in the middle of the night and make your way to the bathroom for a drink of water. Rods and cones differ in several other ways as well, most notably in their numbers.
