🎡 Anomalous Motion Rings
Stare at the central red dot and move your head forward and backward. The rings will magically rotate! Or just click "Auto-Pulse" below.
🧠Pinna anomalous motion
This image is completely static. The "rotation" happens entirely inside your brain. This is known as the Pinna-Brelstaff Illusion.
It works because of the tilt and high-contrast borders of the individual squares. Your visual cortex processes motion orientation. When you move your head toward the screen (or the auto-pulse scales the image), the diagonal edges "shift" locally on your retina.
Because the inner squares tilt one way and the outer squares tilt the other, your brain miscalculates the signals from your peripheral vision and erroneously interprets that local movement as two distinct rings rotating in opposite directions. Try dragging the tilt slider to negative numbers to watch the direction reverse!