Wednesday 22 August 2012

Questions about the History of an Old Illusion

It all began with a weekend trip to a museum in the small northern Michigan town of Cross Village to do some research on a Franciscan named Father Weikamp who had a convent in the village in the 19th century.  My beautiful Jeannie called me into another room and asked me to look at a picture, shown below, and follow the directions.
The directions were to stare at the dots in the center of the image for 30 seconds and then close your eyes.  In a few moments you see a bright circle with an image in it.  You might try it before we go on, and if my image isn't good enough, you can find lots of links to it on the web.  Here is one.



Ok, So I know this is an after image illusion, and I had seen lots of them, but none that seemed like this one. Here are four from Wikipedia. It seems very easy to me to see what all the others are without focusing on any thing in particular; but the fourth seems not at all like the others.

I was curious and started searching for others that would not be obvious before you stared at the image and closed your eyes. My search was without success. If you know of more references, please advise.
My real question however, was about the scientific history of these types of illusions. The subject seems little studied, and according to several references, we are still unsure if it is in the brain or the eye that the reversal occurs.
The Franciscan mentioned above had died in the 1880's so it has to be a phenomenon that is somewhat old, but tracking down the history was even more difficult.
So now I'm searching for historical information on this particular type of burn in illusion. I would appreciate information resources from anyone who has any knowledge of the history.

No comments: