Motion Illusions

Here's a false motion illusion, caused by the cognitive effects of interacting color boundaries.

It looks to me like the tentacles of a colorful creature. The tentacle you're not looking at is the one that slithers forward. Or you might see it as the feet of an Oopsidoofus as he slides his feet into his knitted socks.

The effect usually happens best in the periphery of the retina.

In this peripheral drift illusion, the wheels seem to rotate when the eye scans text.

Thanks, Christopher!