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hole in the sheet of photoreceptors, known as the optic disc, through which the wires leave the eye. You can see this on the photo of the back of my eye that at the top of this guide ? that light disc is the gap in the eye the wires disappear through; you can see the blood vessels converging there too. For that part of the retina where the hole is, there are no photoreceptors, so any light that falls on this space is effectively ignored
by the brain and so cannot be turned into perceptual signals.
You don't notice this hole in your vision normally, because you have two eyes and these both move around, covering up their own blind spots and compensating for each other's. But close one eye, and keep it still, and you can prove to yourself that you normally live with large gaps in your vision.
The Journey
+1 point: find
