pupillary light reflex plr or photopupillary reflex

adaptive anatomy aperture ciliary closeup detail drawing edinger eye eyeball eyelashes eyesight focus function ganglion geniculate health human illustration iris isolated lateral light look medical medicine nerve neurology nucleus ophthalmology optic optical organ parasympathetic pathway person photopupillary plr pretectal pupil pupillary red reduced reflex retinal schematic see tract vision westphal