A group at M.I.T. is using a "magnetic resonance imaging device that used radio waves and powerful magnetic fields to track blood flow in the brain, an indirect measure of neural activity." The short summary is that music lights up a very specific area of the brain and that this is distinct from where it processes all other noise and speech.
Note yellow areas for talk stimulation in top image and yellow area for music area (right behind the ear!) in the bottom image.
If you have a couple of minutes, read the whole article. It is fascinating.
-Bonnie Ward Simon