Acid Trip Illusion

Whoa.

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When it tells you to look away at the end, look at something with contrast and texture, like with lettering. Not the wall. You can keep looking at the video — the effect you see is in your mind, not in the video.

Illusions: Tricking the Eye or Fooling the Brain?

Optical illusions: caused by eye or brain?

For the past 200 years, researchers have debated whether the illusion of motion in a static image is caused by mechanisms in the eye, in the brain, or by a combination of both. Because measuring these kinds of physiological responses is difficult, no study has successfully measured direct and tightly timed correlations between a kinetic illusion and a physiological precursor.