This might just be the closest drug free way of experiencing a hallucination.
Check it out here
If you are epileptic you may not want to click the link.
So what causes this effect?
Here's what Wikipedia has to say on the subject.
Neurons coding a particular movement reduce their responses with time of exposure to a constantly moving stimulus; this is neural adaptation. Neural adaptation also reduces the responses of these same neurons when responding to a stationary stimulus (see, for example, Barlow & Hill, 1963; Srinivasan & Dvorak, 1979). One theory is that perception of stationary objects, for example rocks beside a waterfall, is coded as the balance between the responses of neurons stimulated by upwards movement and the responses of neurons stimulated by downwards movement. Neural adaptation of neurons stimulated by downwards movement reduces their responses, tilting the balance in favour of upwards movement.Easy Explanation:
The motion direction that we perceive is a result of a decision by a majority of our motion sensitive neurons. If some motion detectors continuously respond to motion for a while, they tire or adapt to that motion and become less active. When the motion is stopped, different motion detectors, especially those for the opposite direction, become active, and give rise to the illusory motion in that direction.
(HT Eugene)
Comments
Mild breathing, that's all. Yawn.
But a much better format than the video versions on YouTube.. etc.
Posted by: daksya | March 11, 2007 11:47 PM
That's awesome,
I didn't think it was that great until I looked at the painting on my wall, freaky.
Posted by: Eric Irvine | March 12, 2007 12:07 AM
When I look at it with one eye closed, I get the strong form of the illusion with the opened eye, but when i switch it up, i get a slight illusion with the other one too. neat.
Posted by: Brian | March 12, 2007 1:27 AM
Ah, but this neuronal explanation of the motion after-effect has a problem. Try this:
1) Look at the stimulus linked above for 20 seconds
2) Look away. Time the duration of the after-effect.
3) Look at the stimulus for another 20 seconds.
4) Close your eyes for an equal duration as the original after-effect.
5) Open your eyes and look around. The effect still remains, though not as strongly.
This is known as storage, and it's something that is very difficult to explain with basic adaptive processes of neurons, since there's no reason why they should go back to baseline just as quickly with your eyes open as when closed.
It's not talked about a lot (the Wikipedia entry doesn't even mention it), possibly because no one really knows why it happens. Scientists do have a tendency to pretend that things they don't understand don't exist.
I will have to re-blog this. I've done quite a bit of reading into this stuff.
Posted by: Johan | March 12, 2007 4:50 AM
I finally got around to blogging this. Click my name to learn all about storage (and get another excuse to listen to that lovely techno loop!).
Posted by: Johan | March 31, 2007 4:44 PM