Two different types of activities-substance use and compulsive behavior-increase dopamine output, producing a "feel good" sensation that can trigger and reinforce addiction. Host William C. Moyers talks with recovery expert Brenda Iliff about cross addiction (addiction interaction disorder), the condition of replacing one problematic substance or behavior with another. Iliff explains why addictive behaviors around food, sex or gaming thrive in secrecy and where to find recovery help and support.