Will the world end Dec. 21 in the 'Mayan Apocalypse'? Psychology expert addresses the science of fear

Bob spoke with Prof. Shmuel Lissek of the U of MN department of psychology Dec. 14. Lissek's specialty is the science of fear. They talked about how and why humans react to imagined fearful situations the same as to real ones, and what happens in our bodies and minds when we're afraid.