PHYSL405 Lecture Notes - Lecture 8: Torsten Wiesel, Visual System, Lateral Geniculate Nucleus

• School: University of Alberta
• Department: Physiology
• Course: PHYSL405
• Professor: Yves Sauve

Document Summary

Brain uses edges for conscious vision; are single cells tuned to specific orientation. Orie(cid:374)tatio(cid:374) sele(cid:272)ti(cid:448)e: i(cid:373)age of parallel li(cid:374)es (cid:271)ut (cid:449)e thi(cid:374)k it"s (cid:271)e(cid:374)t. Illusions show you flaws in brain; brain has evolved to detect enviro for survival (not perfect) Lateral geniculate nucleus (lgn): do direct output of retina to cortex; part of thalamus. Only output of retina = rgc = only way to send info to cortex. Recall gates: synapses and formation may or may not make it at synapse. Conscious vision (for vision to be conscious, need lgn) A -no direct projection of rgc to cortex; axons of relay neurons of lgn = optic radiations and synapse most of them on layer 4 of visual cortex (are exceptions) B (cid:862)differe(cid:374)t re(cid:272)ipes(cid:863): differe(cid:374)t i(cid:374)gredie(cid:374)ts: par(cid:448)o(cid:272)ellular, ko(cid:374)io(cid:272)ellular a(cid:374)d (cid:373)ag(cid:374)o(cid:272)ellular. Koniocellular = mixing of the various types of cones into yellow and blue; go between the layers.