PSYC 100 Lecture Notes - Lecture 21: Visual Cortex, Occipital Lobe, Optic Chiasm

• School: McGill University
• Department: Psychology
• Course: PSYC 100
• Professor: Jens Pruessner

Document Summary

Light 1st passes though the cornea (the clear outer covering of the eye). The cornea focuses incoming light in a process called refraction. Lights rays then enter and are bent farther inward by the lens, which focuses the light to form a single image on the retina, the inner surface of the back of the eyeball. Although more refraction occurs at the cornea than at the lens, the lens is adjustable whereas the cornea is not. The pupil is a small opening in front of the lens that determines how much light can enter by dilating or contracting. The iris is a coloured muscular circle on the surface of the eye that changes shape to let in more or less light by controlling the pupil"s size. Behind the iris, muscles change the shape of the lens, flattening it to see distant objects and thickening it to see close objects, this process is called accommodation.