HSC 350 Lecture Notes - Lecture 4: Visual Field, Lateral Geniculate Nucleus, Visual Cortex
Document Summary
Comprises complex neural circuitry that converts the graded electrical activity of photoreceptors into action potentials that travel to the brain via axons of the optic nerve (cranial nerve ii). A direct three neuron chain photoreceptor cell to bipolar cell to ganglion cell is the major route of information flow from photoreceptors to the optic nerve. Horizontal cells and amacrine cells mediate lateral interactions. There are two types of photoreceptors: rods and cones. The short axonal processes of bipolar cells make synaptic contacts in turn on the dendritic processes of ganglion cells, the large axons of which form the optic nerve and carry information about retinal stimulation to the brain. Refer to slides for details on receptive fields etc . Ganglion cells axons in the optic nerve project to the optic chiasm at the base of the diencephalon. About 60% of these fibers cross in the chiasm, the other 40% continue on the same side.
