When we look straight at an object we see not only the object focused on, but also the objects to the side of it, which is defined by limits on all directions. this is the visual field.
Scotoma is a non seen area within a seeing area. it can be due to disorders of the optic nerve, the nerve which connects the eye to the brain or macular problem-the central area within the eye which is responsible for central fixation of the eye.
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