Dancing Dots

Between the black squares, which form a sort of network in the image, black dots appear among the lighter circles where the white lines meet. When we look more carefully, we see the corners of the square pattern more clearly. The distance between the pupil of the eye and the various visual cells of the retina affect what we see. Vision cells known as “rods” are located out towards the periphery of the retina. The rods are visual cells used to see in the dark. The strong contrasts and the continuous motion of the eye are two factors that cause this illusion.