Nothing to do with memory, but a reminder about the nature of our sensory apparatus, and our brain. What we perceive seems so direct it's hard to believe that it's really a construction of our brain, but so it is. Perception, like memory, is all about information coded in the brain. It's all about patterns of neurons firing, after all. And the difference between, say, sight and sound, is not as far as it seems. Here's a site with software to turn sound into "vision", for those who can't see, and here's an article about it. And if you don't really believe that we construct the world we see, check out this demonstration of the blind spot.