[url=http://www.amazon.com/gp/product/1557983402/qid=1141245334/sr=1-2/ref=sr_1_2/002-2123563-5099201?s=books&v=glance&n=283155]Amazon link[/url]
While it's more about the concept of patients imagining things and creation of false memories, part of the book is dedicated to a critical analysis of the hypnotic method and if it can really bring people into a "different state". What is argued is that there is no physiological basis for a state of hypnosis, but is instead a sociocognitive phenomenon. All in all, a good skeptical analysis of the concepts commonly associated with hypnosis. Spanos has gone into more detail in other works, but those were mostly research papers, not books.