We’ll take a look at the psychology behind hoarding and how we can learn to purge what we don’t need and live with less. Michael Rossato-Bennett on his documentary “Alive Inside,” about the healing power of music. He’ll be joined by Dan Cohen, founder of Music & Memory, who uses music to treat Alzheimer’s patients. We’ll find out about how the things Marlon Brando read, collected, and cared about influenced his performances. Ian Gordon, editor at Mother Jones magazine, on what happens to the unaccompanied child immigrants who are sent back home after they’ve crossed into the United States.