Our eyes are constantly reading visual information, but the brain is often in a hurry to draw conclusions. This quality developed in us thousands of years ago, at a time when we had to fight fast, bloodthirsty predators, but made us absolutely helpless in the face of simple visual effects.
The moment we look at light, it is immediately converted into electrical signals, which then our brain turns into images. This takes about 1/10 of a second, so we are talking about huge amounts of visual information perceived by us.
One example is the so-called Hering's illusion, when 2 identical parallel straight lines are perceived as having changed their shape, size and angle. When faced with a radial pattern, they appear deformed, although in reality they are perfectly straight.
And here are 2 other parallel lines, but it is worth drawing multidirectional arrows on their edges, as an illusion arises that one of them is larger than the other.
Looking at these 6 coils, it seems that they are rotating, although they remain stationary. The effect is best seen on peripheral vision. When we concentrated our attention on one coil, then it is really stationary, and its “neighbors” are rotating.