Before a pattern can be desired by the brain, it must play hard to get. Music only excites us when it makes our auditory cortex struggle to uncover its order. If the music is too obvious, if its patterns are always present, it is annoyingly boring. This is why composers introduce the tonic note in the beginning of the song and then studiously avoid it until the end. The longer we are denied the pattern we expect, the greater the emotional release when the pattern returns, safe and sound. Our auditory cortex rejoices. It has found the order it has been looking for.
I find this fascinating in its own right, and it causes me to speculate on something I’ve discovered over the years: I love a good academic or theological lecture, and find I am most stimulated when I am challenged at the outer limits of my understanding. I wonder if this is when and how true learning takes place – when the brain is actively making connections between what is already there (in one’s brain) and something brand new, and that this connection is enhanced (as in the enjoyment of music) by the surprise factor. (The “aha!” of learning being the intellectual cousin of the emotional response to music.)
There seems also to be an obvious connection between the studies of the brain’s response to music and reports that the aging brain is kept healthy by continuing to learn new things and departing from routine (as reported in this recent New York Times article).
On a more mundane level, this is why the Saturday New York Times crossword is more enjoyable than Monday’s.