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stevesnj · Jan 30, 2006, 12:31 AM

If your eyes follow the movement of the rotating pink dot, you will only see one color, pink.
If you stare at the black + in the center, the moving dot turns to green.
Now, concentrate on the black + in the center of the picture. After a short period of time,
all the pink dots will slowly disappear, and you will only see a green dot rotating if you're lucky!

It's amazing how our brain works. There really is no green dot, and the pink ones really don't disappear.

This should be proof enough, we don't always see what we think we see.

dcmacdaddy · Jan 30, 2006, 12:36 AM

Craziness. Good Find.

I think that is an illustration of the phenomena known as "Persistence of Vision". This idea says that if something occurs in our field of view repeatedly, after a while our brain will interpret it as being there even if it is not. After a while our brain "puts" the green dots in a circle even though they are not really there. or something like that.

spatterson · Jan 30, 2006, 01:22 AM

wow... thats crazy! I wouldn't imagine them disappearing! Neat find!

euchomai · Jan 30, 2006, 01:51 AM

That is great, I just passed the iBook around the room and blew my friends minds.

KeriVit · Jan 30, 2006, 02:01 AM

Very nice. Even though I am blind in one eye, it works for me- a lot of op stuff doesn't. Thx.

euchomai · Jan 30, 2006, 02:02 AM

Originally Posted by KeriVit

Very nice. Even though I am blind in one eye, it works for me- a lot of op stuff doesn't. Thx.

Man, we are learning a ton about you today!

KeriVit · Jan 30, 2006, 02:05 AM

Originally Posted by euchomai

Man, we are learning a ton about you today!

well , all ya had to do was ask...

- - e r i k - - · Jan 30, 2006, 06:41 AM

Bad ass illusion. Now does anyone have the Bug-eyed one with the spiral you had to stare at to make your vision all funky for a few seconds afterwards? It was available as a classic program years ago, but I haven't seen it online.

turtle777 · Jan 30, 2006, 10:06 AM

Wow, amazing.

-t

Mastrap · Jan 30, 2006, 10:09 AM

Pretty damn cool. I love how the dots disappear completely when you concentrate on the cross in the middle.

How does this work?

starman · Jan 30, 2006, 10:23 AM

Here's how it works - try this:

Stare at something, anything, that's a true color (blue, reg, green), now move your eye to a blank sheet of white paper and stare at it. You see the negative image. If you stared at green, you see red, stare at blue, you see yellow.

Notice how the dots don't show up until AFTER the first cycle?

wdlove · Jan 30, 2006, 10:35 AM

Very interesting, like the illusion.

wolfen · Jan 30, 2006, 10:43 AM

I can't explain all of it, but I think I remember that Red and Green are processed by different cones within the eye. This is why surgeons have green garb-- looking at green relaxes the eye after they've been staring at Red guts for too long.

You can see that this purplish tone and puke green tone share a similar relationship within the eye. Probably has something to do with some cones being turned off by the green dot, making the purple dots invisible.

turtle777 · Jan 30, 2006, 10:44 AM

Originally Posted by wdlove

Very interesting, like the illusion.

[hypnotic voice]
WDlove, listen to me.
You are a pancake now. With jelly on it. Do you copy ?
[/hypnotic voice]

-t

Doofy · Jan 30, 2006, 11:14 AM

Sweet.

BRussell · Jan 30, 2006, 12:12 PM

That is the coolest afterimage effect I've seen. I like the pacman effect, where it looks like the (non-existent) green dot is eating all of the (real) pink dots.

wolfen - the afterimage effect isn't in the cones in the eye, it's an effect on the neurons in the brain. You're tiring out the neurons that process color, resulting in the opposite color.

greenamp · Jan 30, 2006, 12:31 PM

Originally Posted by BRussell

That is the coolest afterimage effect I've seen. I like the pacman effect, where it looks like the (non-existent) green dot is eating all of the (real) pink dots.

wolfen - the afterimage effect isn't in the cones in the eye, it's an effect on the neurons in the brain. You're tiring out the neurons that process color, resulting in the opposite color.

I thought afterimages were a result of the cones in your eyes tiring?

BRussell · Jan 30, 2006, 02:02 PM

Originally Posted by greenamp

I thought afterimages were a result of the cones in your eyes tiring?

Hmm some internet searches say that you're right, it is the cones tiring out. My understanding was that the afterimages were the result of opponent processes further back in the circuit.

paul w · Jan 30, 2006, 02:07 PM

Originally Posted by KeriVit

well , all ya had to do was ask...

That smiley makes perfect sense now. Heh.