This is a common optical illusion that I have seen in any number of books. It was tweeted out this morning by Brain Games. Normally, I wouldn’t present it to you because it really isn’t that interesting. I mean, some optical illusions are more interesting to certain kinds of people than others. Personally, I most like optical issues that look different depending upon how you approach them (eg two faces and a vase). So in the past, I’ve passed it (and similar ones) off as, “Oh, it disorients the eye.” But I noticed something different this morning.

For the record, this is not an animated gif or anything like that. It is one stagnant image. How it seems to work (and I have done no research whatsoever) is by confusing our binocular vision. Try this. Don’t look at the image generally. Stare are one spot in the image. It will stop moving. It is quite interesting to see what happens when you move your focus to another spot on the image. It starts to move and then again stops. This also happens if you focus on a spot outside the image. The same thing happens if you focus your gaze at infinity, the image stops moving. But that is effectively doing the same thing: you are focusing on a single place.

What is most interesting to me is how my perception of the image has changed. When I first looked it, the image moved so much that it was dizzying—and annoying in the extreme. But now, I have a real hard time getting the image to move at all. About the only way I can get it to move is by focusing on a spot in one corner and then moving my focus to another corner. And even then, it moves in fits and starts. It has lost all of its kaleidoscopic charm.

It will be interesting to see if I stop looking at it for a day or so, if the original dizzying quality will come back. Or even more interesting, if other types of these optical illusions would now have the same problems for me. My guess is that they are all ruined for me right now, but that within a day or even an hour my brain will be back to normal.