Cognitive Daily

Optical illusions!

Here are a few neat optical illusions.

1. Multi-colored X?

(via Grand Illusions)

It appears that the X is two different colors, but it’s actually made using just one shade of pink.

(more below)

2. Is this a circle?

(via eluzions)

It is indeed.

3. Some classic illusions embedded in an animated video:

Hope you enjoyed these!

[Mainly this is to distract you from the fact that there is no Casual Friday post today. There was a billing problem with our survey provider. I fully expect Casual Fridays to be back next week]


  1. #1 Michael Bach
    October 28, 2007

    It’s a little disappointing that this fine site follows the general trend in illusions to follow the crowd and neglect source and background — at least the original names could be given. The first is a variation of the Munker-White illusion, the second belongs to the angular illusion class (Hering, Orbison or Wundt illusion)… Having vented, chagrin is gone, thank’s for listening¬†;-), best, Michael.

  2. #2 Wicked Lad
    October 29, 2007

    That “Multi-colored X” reminds me of this same-color illusion from Edward H. Adelson at MIT. I literally didn’t believe that one when I first saw it. Had to cover up various parts of the screen before I conceded the two areas in question are the same shade. Amazing.

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