The Phantom Piano

When the brain goes awry, it can reveal to us some clues to how it works in all of us. In my latest “Matter” column for the New York Times, I look at a rare but fascinating disorder that causes people to hallucinate music. How someone could imagine that a piano was playing nearby–or a marching band or church choir–may tell us something about how our brains make sense of the world by making predictions about what comes next. Check it out.