PSYC 2390 Lecture Notes - Lecture 3: Retinal Pigment Epithelium, Ciliary Muscle, Wavelength
Document Summary
Electromagnetic radiation: amplitude - brightness, wave length (nm) colour. Cornea focus/bend light 80: corneal disease -> halos, rainbows. Retina gathered (upside down: photoreceptors pigment (colour) If isomerized retinal and opsin split causing bleaching clear. When split apart it cannot absorb anymore light. Chemical reactions that result in action potential: change in colour for a short period of time causes the action potential. Rods most common, good in low light. Have more spatial summation/convergence of rods onto one ganglion cell, allows ganglion to be more sensitive to low light (blur of light) Photopigment is rhodopsin (very sensitive: absorbs blue and green, therefore doesn"t a(cid:271)sor(cid:271) red, doesn"t pi(cid:272)k up long (cid:449)a(cid:448)e lengths (cid:448)ery (cid:449)ell, takes a long time to regenerate (after bleaching) Pigment regeneration (requires pigment epithelium to put retinal and opsin back together again) Takes about 30 min for rhodopsin to regenerate. No rods in the fovea, tons in the periphery.