ACTIONS THAT FEEL REWARDING typically feel that way because, if we continue them, we are more likely to survive as a species. That's why elements of music puzzle scientists. Music can't make you feel full if you're hungry or help you pass your genes on to the next generation. But music, like all of these things, can still make you feel inexplicably good.

There's something about it that tickles the brain anyway. When that happens, music can ignite literal chills.