Learning to play a musical instrument changes the brain.
http://www.articlesbase.com/art-and-entertainment-articles/b...
http://www.articlesbase.com/art-and-entertainment-articles/b...
Perhaps learning music changes the brain in a way that is different than say, learning how to cook French food or to fix a computer?
Additionally, I find that when programming a short musical break will rejuvenate my mind and get me right back into the flow of code.