dean13 sent around this link to a Very Cool optical illusion. I did it several times to see if it would affect the sequence, speed, or pattern of the illusion for me. (It didn't.) And for my last "trial," I kept watching for a while after all the pink dots had disappeared. My results:
1. The moving pink dot goes green very quickly, within a second or two of focusing on the black cross. I then see a green dot cycling clockwise through a circle of pink dots.
2. The pink dots disappear rapidly afterward, usually as the "green" dot sweeps over them. They go in swatches or clumps--several at a time in sequence. That is, the "green" dot swipes some off in one circuit, then another in the next, until they're all gone. I do, occasionally, have some just fade out, without having been swept over by the green dot, but again it's not individual dots but several in a sequence.
3. A green dot remains, circling in clockwork fashion.
After my last, longer trial, the pink dots fade in and out, also in swatches. They tend to be fainter than they were originally. I did get a return of the whole pink circle with the green dot circling them briefly, but they quickly got "wiped" out again.
dude_the, who is dyslexic and has some eye musculature wonkiness, had a different effect from the illusion; he had a harder time in general getting the pink dots to disappear. I'm really curious if and how the pattern of the dots disappearing across individuals correlates to reading strategy and speed. Also whether the illusion would manifest differently for an autistic person.
Okay, I recently broke down and made a foray into the hullabaloo which is MySpace.com (user name "eugiefoster"). I found and friended some of y'all, but for those of you I didn't, I'd love it if you could give me a myspace hello. (Although I'm still not sure what the fuss is all about.)
And while I'm pimping, buy the shiny new magazine:
great jiminy. that is one of the weirder ones that i have seen.
myspace: i signed up for an account briefly, but did not confirm it because it freaked me out a bit. i was looking for NCSU classmates, did not find anyone I recognized and the random people all looked like they were prowling.
The pink dots turned green and then vanished very quickly for me, but I found that if I looked away -- to read the text above the dots, for example -- the pink dots immediately returned until I focused on the middle of the circle again.
Crazy stuff! Our brains and perceptions are amazing things. You've heard about the inverting-lenses experiment, I presume, where people had lenses taped over their eyes that made everything upside down? After awhile their brains adjusted to this and flipped the image so they saw things right-side up again. Just goes to show that perception is not purely a matter of input; there's a lot of processing going on in there.
"You've heard about the inverting-lenses experiment, I presume, where people had lenses taped over their eyes that made everything upside down?"
Yes! I was totally floored when I learned about it in school. Brains are cool. And weird.
My current hypothesis on why I have a harder time getting the pink dots to disappear is due to my ADD rather than tracking difficulties and the like. I have a really hard time not shifting focus to something that is moving in a repitious patterns (which makes screen savers evil, evil things).
The green I'm certain now is the color fatigue effect, where you get an inverted color afterimage after looking at intense colors due to a delay in the recharging of the cones on your retina.
It seems to me as though your brain is averaging out parts of the image that aren't changing and you aren't focusing on, which causes the pink dots to disappear. The green one remains, though, because your retinas are still receiving the pink stimuli. Your brain continues to ignore the pink, but you see the phantom green dot because of the fatigued retina feeding it back as a change.
There are a few holes in that hypothesis, but it works for now.