Normally, the photoreceptor nerve cells of the retina change the light rays
into electrical impulses and send them through the optic nerve to the brain
where an image is perceived. But any stray electrical impulses in the optic
nerve or in the area of the brain that processes vision, may also cause
images to be perceived by the brain.

The fact that the images you see are "dimly flickering dots" is not
surprising, sort of like a really bad TV signal connection that only
contains random noise, and not a clear image on the TV set.