A new study says yes:
New research shows that musicians' brains are highly developed in a way that makes the musicians alert, interested in learning, disposed to see the whole picture, calm, and playful. The same traits have previously been found among world-class athletes, top-level managers, and individuals who practice transcendental meditation.
[Those with high mind-brain development, such as musicians] have well-coordinated frontal lobes. Our frontal lobes are what we use for higher brain functions, such as planning and logical thinking.... Yet another EEG measure shows that individuals with high mind brain development use their brain resources economically. They are alert and ready for action when it is functional to be so, but they are relaxed and adopt a wait-and-see attitude when that is functional.
Musicians also exhibit higher levels of moral reasoning and have more peak experiences. Fascinating stuff.