There's a book called "The Like Switch" which is written by a former FBI behaviorist who has devoted his career to answering questions including this specific o

There's a book called "The Like Switch" which is written by a former FBI behaviorist who has devoted his career to answering questions including this specific one. It has specific answers to your question complete with studies and war stories to back it up. Fun reading! [1] http://www.goodreads.com/book/show/21412226-the-like-switch http://www.goodreads.com/book/show/21412226-the-like-switch