This is an interesting point, because while I find it trivial to work with geometric objects in my head (see my other post in this thread), I find it very hard

This is an interesting point, because while I find it trivial to work with geometric objects in my head (see my other post in this thread), I find it very hard to recall a face as anything other than "a face". I recognize people just fine, but if you sat me down with a sketch artist (or indeed the sketch-artist sub game in Police Quest II), I'm at a loss to say whether someone's eyes are wider or narrower-spaced, whether their mouth is higher or lower, etc. Sometimes I do notice people's noses in the abstract and I may have a describable memory of that, and I think I remember most people's hair shape if not the color. But "A face with a small nose and long hair" is not really much to go on. Smells, too. I smell just fine, and sometimes smells evoke instant memories, but I can't name a smell that I'm smelling. I'm absolutely at a loss to figure out what herbs are missing from food I'm making, or what I've added too much of. I can't describe tastes or smells beyond a very basic level.