|Optical illusion that lasts for days!|
|Posted by: Digg on Jul 3rd, 2006 1:00 AM|
|It is called the McCollough Effect, and was originally described by Celeste McCollough [...] It has been the focus of on-going investigation ever since.
The precise cause of the effect is unknown, and currently under investigation. [...] There are neurotransmitters involved and appear to be responsible for the long-lasting nature of the effect.|