PSYC1004 Lecture Notes - Lecture 1: Lateral Geniculate Nucleus, Optic Chiasm, Superior Colliculus
26 Oct 2018
School
Department
Course
Professor
Document Summary
Transduction in the eye: image is focused on the retina, photoreceptors bleach, bipolar cells are excited, ganglion cells fire, information is transmitted from the retina to the brain through the ganglion cells which form the optic nerve. Impulses from the optic nerve first pass through the optic chiasm where the optic nerve splits. Information from the left side of the retina goes to the left hemisphere and vice versa. Once past the optic chasim, combined info from the two eyes travel to the brain via the optic tracts (a continuation of the axons of the ganglion cells). From the optic nerve, visual information travels along two pathways: superior colliculus in the midbrain (short pathway): projects clumps of neurons in the midbrain known as the superior colliculus, which in humans is involved in controlling eye movements. Its neurons respond to the presence or absence of visual stimulation in parts of the visual flied but cannot identify specific objects.
