Music moves along/triggers interesting neural paths.
I was just reading Oliver Sacks’s book Musicophilia. There is an interesting discussion – don’t have the text to hand to give page numbers – about this kind of musical practice. Apparently with music, and in essence not with pretty much anything else (nobody quite knows why), when you run through a piece you know well, just in your mind, your brain triggers all kinds of flashes and systems that one would usually associate with motor activity, even though your fingers and such don’t actually move. In other words, memorizing music in terms of performance – that is, memorizing a piece to play it rather than just by listening to it – appears to get literally embedded in motor areas of the brain. This does not appear to happen to a significant degree, nor with this level of complexity, with other kinds of memorized systems. And it’s not just motor stuff either: music triggers weird systems and regions of the brain in ways that are wildly atypical and pretty much unlike anything else. Nobody knows why music should be this way, but it has lots of manifestations. For example, musicians afflicted with such neurological pathologies as parkinsonism and Tourette’s syndrome often completely drop the symptoms when they take up their instruments – Touretters don’t tic, parkinsonians regain full muscular control, Alzheimer’s-type dementia sometimes affects pretty much everything except memorized music (however complicated), and so on. Conversely, this means that it is possible (if rare) for someone to be completely incapable of comprehending music, at a deep neurological level – i.e. there are special musical defects in the brain – without this having any predictable effects (or possibly any effects whatever) in other areas of cognition, behavior, etc. (To put that very simply, compare to blindness. At least at a basic level, a blind person’s brain is capable of understanding visual stimuli; although those systems may be pretty much atrophied, they exist. A person with these kinds of amusia actually cannot understand music.