Eidetic (photographic) memory

There were lots of really good questions and comments on the topic of eidetic memory towards the end of class today. Noah mentioned the expert chess players who could recreate pieces on a chess board from memory. Here's some more information on this topic:

"Scientists who study memory phenomena generally believe that eidetic memory (more popularly known as 'photographic memory') does not exist. Early experiments on eidetic memory were intriguing, but could not be replicated.

People do show extraordinary memory performance in certain circumstances. For example, expert chess players can typically play blindfolded chess against several opponents at the same time, easily memorizing many chessboard configurations. Others use special tricks to memorize long lists of randomly selected numbers.

Impressive as these feats are, scientists attribute them to specialized ways of thinking about the information, not to any kind of enhanced visual memory. One interesting experiment that makes this point was performed by a cognitive psychologist named DeGroot. Expert chess players were shown a chess board with pieces on it for a brief period, such as 15 seconds, and then asked to reconstruct what they had seen on a new chess board. That is, they were asked to place chess pieces in the same positions as they had appeared on the board they'd been shown. The expert players were very good at this, much better than novice players. One hypothesis was that the experts had developed an enhanced ability to memorize visual information.

In the next experiment, the expert chess players were asked to do the very same thing; but this time, they were shown boards whose pieces were arranged in ways that would never actually occur in a game of chess. Not only did their ability to remember the positions go down, but it went down all the way to the level of the novice players. We can conclude that the original, enhanced performance at remembering chess positions came from the experts' ability to mentally organizethe information they had observed, not from any ability to 'photograph' the visual scene."