Alan Alda on fighting Parkinson's with laughter

Alan Alda, now 90, is one of the country's most-beloved actors, best-known for his role as "Hawkeye" Pierce on the classic TV series "M*A*S*H." Alda talks with CBS News chief medical correspondent Dr. Jon LaPook about his challenging childhood, dealing with polio and his mother's schizophrenia; his decades of work to help scientists and health care professionals communicate more clearly; and about living with Parkinson's disease, which he refuses to let define him.