Horizon: How Does Your Memory Work?

How does the human memory work? The stories of John and Genevieve are helping scientists to understand. John's memory was damaged at birth. Although he is intelligent, he can't catch a bus or cook a meal because he forgets what he is doing. Genevieve's problem is the opposite - she wants to forget. She is haunted by a sexual assault and suffers from post-traumatic stress disorder. A pioneering technique could erase her memory with a pill.