Your lyin' eyes - 2

The blue and the green. Take a look at this optical illusion, which proves that the images we perceive are not direct input from the eyes, but considerably processed by the brain before reaching the conscious mind. In other words, what you see is not necessarily what you are looking at.

And do take a look at the site whence it came, that of Akiyoshi Kitaoka. Much more of this there. There is a warning on the front page: "Warning: This page contains some works of 'anomalous motion illusion', which might make sensitive observers dizzy or sick. Should you feel dizzy, you had better leave this page immediately." So be warned. I will not be responsible for your keyboard if you toss your cookies. By way of Rand Simberg.

Your lyin' eyes

Eyes not always the most reliable witnesses:

The three best visual illusions in the world were chosen at a gathering last weekend of neuroscientists and psychologists at the Naples Philharmonic Center for the Arts in Florida.

Go see them. See all the finalists. (The "Tilt Illusion" is not working for me, though the Silverlight test page says it's installed correctly. I don't know.) Thanks to Jonah Goldberg.

Related: Perception test.

Perception test

Here. As John Derbyshire says, "Don't read anything, just watch the video." (via)

Update: It didn't take long for that to get yanked from Youtube. The original is still online, but you'll need a little setup: You will see some people in white shirts and some people in black shirts. Each group has a basketball. Try to count the number of times the people in white shirts pass the basketball. OK, now watch the video. (Java is required.) What was the number? Now read the first comment.

Update: Here is another version of this, with Simon Baker as Patrick Jane doing the setup. Regular Youtube, no Java required, only the usual FlashPlayer.

Update, Dec. 12, 2010: Big Think has an interview with Prof. Christopher Chabris of Union College on our illusions about our ability to perceive and remember. Chabris has written a book, with Daniel Simons, called The Invisible Gorilla, inspired by the perception test that inspired this post. At the book's website are a number of videos with this among them.