Each retina carries a patch with no photoreceptors at all, where the optic nerve leaves the eye, and yet we never notice a hole in the world. In brighter light the pupil constricts, always with its faint restless hippus; as an object comes closer the lens bulges to accommodate. Every disorder eats the visual field in its own way: glaucoma takes the periphery first, while macular degeneration bends straight lines and darkens the very centre.
Each retina carries a patch with no photoreceptors at all, where the optic nerve leaves the eye, and yet we never notice a hole in the world. In brighter light the pupil constricts, always with its faint restless hippus; as an object comes closer the lens bulges to accommodate. Every disorder eats the visual field in its own way: glaucoma takes the periphery first, while macular degeneration bends straight lines and darkens the very centre.
Related topics in Human Body