Importantly, the M.I.T. team demonstrated that the speech and music circuits are in different parts of the brain’s sprawling auditory cortex, where all sound signals are interpreted, and that each is largely deaf to the other’s sonic cues, although there is some overlap when it comes to responding to songs with lyrics.

I've long had a pet-theory that music with voices in it interrupts my train of thought (especially while programming) in a way that instrumental/electronic music avoids.

Of course, if unnamed scientists discover that listening to voices is completely separate from writing text, that'd be evidence against it.