PSL300H1 Lecture Notes - Lecture 23: Retina, Suprachiasmatic Nucleus, Metabotropic Glutamate Receptor 6
Document Summary
Cones & rods bipolar retinal ganglion brain. Light-sensitive neurons: transduce photons electrical energy (phototransduction) 2 types: rods (120 million, cones (60 million) Point towards the back of the eye (counterintuitive layout) Each photoreceptor 1 pigment: rods rhodopsin, cones 3 different types, m-cones, s-cones, l-cones. Not equally distributed: high density in, macula (center of the retina, fovea (middle pit of macula) High density areas = more acute vision. Fovea- covers 2 of visual field: 5 away from centre 25% less acuity, 20 away from centre legal blindness. At the location the optic nerve leaves the eye: no photoreceptors in the hole. Different locations for each eye: information from 1 eye, can fill in the details lost in another eye. Brain very efficient in filling in logical information into the spot. Cones less sensitive: respond to bright lights, don"t operate in dim conditions. Rods very sensitive: single photons are detectable, operate only in dim light.
