Try staring at the black cross in the centre of the image. Now move your heard back and forth, towards and away from the screen in a quick motion. Do the circles move?
This is another simple optical illusion that uses black and white and perspective to trick our senses. Our eyes are focused on the centre point, which stays still, and on the periphery of our vision the black and white points of the circles will appear to move because we cannot lock them down in our vision and because they give the illusion of moving out towards us.
Stare at the cross and quickly move your head
forward and backward, towards and away from the
screen. The circles will appear to be moving.
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