OK. Maybe you're in your desk chair. You're in your office. You're in New York, or Detroit, or Timbuktu. You're on planet Earth. But where are you, really? This hour, Radiolab examines the bond between brain and body, and looks at what happens when it breaks. Author and neurologist Oliver Sacks tries to find himself using magnets, we talk to a neuroscientist who uses an optical illusion to solve a century-old mystery that haunts some amputees, and pilots describe surviving out-of-body experiences while flying fighter jets.