Here are some quotes from various articles on the subject. On the basis of observations and experiments with newborns, neuroscientists now know that infants are born with neural mechanisms devoted exclusively to music.
Studies show that early and ongoing musical training helps organize and develop children's brains.
School leaders affirm that the single most critical factor in sustaining arts education in their schools is the active involvement of influential segments of the community in shaping and implementing the policies and programs of the district. Lewis Thomas studied the undergraduate majors of medical school applicants. He found that 66 percent of music majors who applied to medical school were admitted, the highest percentage of any group. Forty-four percent of biochemistry majors were admitted. Students who study music and the arts score higher on the verbal and math portions of the SAT than students with no coursework or experience in the arts.