It happens everywhere: offices, schools, even your own backyard. And, seemingly, anything can trigger it: cell phones, sirens, bad music, constant distractions, your boss, or even your spouse. We all know certain things get under our skin. Can science explain why? NPR's Joe Palca and Flora Lichtman take you on a scientific quest through psychology, evolutionary biology, anthropology, and other disciplines to uncover the truth about being annoyed.