Two or three million people in the U.S. are living with Obsessive-Compulsive Disorder--more, if you add in the half-million children and teenagers coping with OCD. Their brains are sending danger warnings about some recurring thoughts, and they try to calm their anxiety by repeating some procedure or ritual. We’ll hear from two therapists: Hannah Breckenridge has been dealing with OCD herself since she was a child. And Jon Hershfield, who’s written books about it, heads the ‘OCD and Anxiety Center of Greater Baltimore’.