Just another thought... our brains don't just store strings, or numbers, but also video, audio, all the other senses, and abstracts (feelings, moods). I think the data structure would be more like a three-dimensional mesh, with various processes (dreams, for example) dancing around creating new interconnections between elements.
What I don't understand so well is how I can read a chapter of a book very slowly and methodically and not remember much more than vague ideas 10 minutes later, but if I speed-read the same amount of text (about 10 pages per minute), I actually retain much more of it (short term, anyway -- I did it all the time for a particular class that required a lot of outside reading for in-class discussion).
--isotope
http://www.skylab.org/~isotope/