Pain is physical. But it's also mental. And that mind-body connection is the subject today of "On Pain," our new series about pain management. Greg Whisler had chronic pain for years until he took part in a pain study at CU Boulder, involving a treatment called Pain Reprocessing Therapy. For more on the study, we're joined by Yoni Ashar, the researcher who conducted it, and by Dr. Karen Knight who is a pain management physician in Golden.