In the early 80’s, when Dr. Mark George was studying at the Medical University of South Carolina, he was told to stay away from the vagus nerve. “I learned to avoid the nerve—that anything associated with it was dangerous,” says Dr. George, now a distinguished professor of psychiatry, radiology, and neuroscience at that same school. That's changed in the last decade or so: The understanding of the vagus nerve, which connects the brain to a bunch of internal organs fundamental bodily functions, has evolved dramatically. So too have the directions about not going near it. In fact, vagal nerve stimulation has proven successful in treating everything from epilepsy to obesity.