We've had various threads now and then about how the act of reading, of our brains' comprehending the meaning of the words, activates various centers of the brain. If you're interested in this sort of thing (and I am), you might check out Livia Blackburne's blog here. She is a writer and budding neuroscientist at MIT whose research involves just that issue. It's perhaps a Quixotic goal -- to relate how different sorts of writing affect the brain in different ways. Her blog also has oodles of links to other interesting places that discuss the same thing.