Actress Marilu Henner is one of the rare documented cases of Highly Superior Autobiographical Memory in the world. It's an ability that allows her to vividly recall every detail of every day of her life since childhood. Henner is a consultant to the CBS tv show "Unforgettable," in which the main character has HSAM. Diane also speaks to Dr. James McGaugh who diagnosed this ability and studies people who have it. A discussion with Marilu Henner on what it means to remember your life in detail and what HSAM tells us about the brain.