Use number keys to change the picture: 1. Blue Circles 2. Hearts 3. Tilted Square 4. Circle 5. Snakes 6. Cone and Sphere 7. Waves 8. Rollers 9. Staircase 0 (Bonus). Fading Picture Pictures 1-4: Gently shake your device, and the circles, hearts, or square should appear to jiggle, this is not a video, just a picture. You can screenshot this and look at the picture to prove it. 1-2: If you get closer to the image quickly, the circles or hearts appear to grow slightly, if you back away quickly, they appear to shrink slightly. Pictures 5-9: Slowly move your eyes around the image, the snakes rotate, the waves flow around, the rollers roll, the staircase rotates, and the cone and sphere roll as well. If you stop moving your eyes, the image stops moving (most images move in the places where you are not looking). 0 (Bonus): Do not look away, do not let your eyes become unfocused, do not blink, do not squint too hard, do not focus too hard. Look at the blurry image for about 20 seconds, and it will slowly fade away (stare about in the center of the image). Not many people can do this one, can you?
The reason for this happening is that your visual system struggles to separate your eye and device movement from image movement, causing the picture to appear shaking, jiggling, or moving. The image itself does not move. On the bonus one, as you continue to stare at the image, the neurons in your nervous system stop responding to stimulation. This is called the Troxler Effect, and it was discovered in 1804 by physician Ignaz Paul Vital Troxler.