In this special episode, Susan Rogers, a record producer turned cognitive neuroscientist, and Daniel Levitin, author of “This Is Your Brain on Music,” get together to discuss what music has meant in their lives, debate what separates a great artist from a generic one, and share some of their favorite tunes. --- Susan’s new book, “This Is What It Sounds Like,” was chosen by our curators — Malcolm Gladwell, Adam Grant, Susan Cain, and Daniel Pink — as one of the eight best works of nonfiction published last year. She recently made a beautiful video e-course about the book, which you can experience by downloading the Next Big Idea app.