There is this great book called Musicophilia by Oliver Sacks. It is basically how music affects the brain, and is filled with stories about patients who lacked some skill, or had some talent, or disorder that was correlated to music. I really do not give this book enough credit with my words, just read it, it's fantastic!
There is this chapter within however that is about people who have synesthesia; a process in the brain where two perceptions are welded together(such as: sound --> color). Synesthesia has many variations, however Sacks only writes about the musical ones.