Positronic Brain Neurology

Wow, am I ever a nerd! I say this because just now I was trying to find some sort of schematic for positronic brains online. Yes, I know that positronic brains don't actually exist as of yet but that's not the point. I want to at least get some idea of what they look like. Yes, I'm aware that Data from Star Trek: TNG had a positronic brain and that the inside of his head was shown on more than one occasion. That, however, isn't enough for my curiousity. I actually want to know more of how one of these artifical brains work. The description that Asimov gives in "I, Robot" is /really/ vague. Plus, no one else really seems to fully know the ins and outs of positronic brains either or at least not from what I've found. So seriously if you can find a schematic or a clear description of the workings of the positronic brain than please leave a comment and a link to a website that gives either or both of those. I'd be extremely pleased.