A boy dances like a chicken; strutting around the stage gingerly while rumbling his throat to produce a farmer's wake-up call. The audience erupts in laughter, convinced what they're seeing is a product of the Hypnotist's genius. With a snap of the hypnotist's fingers, the boy regains himself groggily, and asks the question, "What happened just now?".
Hypnosis, at least the public perception of the psychological phenomenon, is one of the most mainstream psychological concepts in the world. However, hypnosis is defined in our text as, "[a] set of techniques that provides people with suggestions for alterations in their perceptions, thoughts, feelings, and behaviors". But the true use of hypnosis is much more important and controversial than a simple stage show to entertain an audience. In fact, the idea of the hypnotized person suffering from amnesia after their ordeal is a total myth. Spontaneous amnesia is "rare and mostly limited to people who expect to be amnesiac following hypnosis"(Lilienfeld). Subjects are also carefully selected before the performance based on their high suggestibility, making them more likely to participate or "believe" they've been hypnotized.
There is still much debate, however, about the effectiveness of hypnosis beyond the stage show. Hypnosis is generally considered to enhance the effectiveness of "psychodynamic and cognitive-behavioral psychotherapies". Most hypnotists utilize an induction method, such as a physical object or suggestions for relaxation and kindness. Hypnosis is often used for treating pain, medical conditions, and habit disorders. Despite the common practice however, there is no evidence that hypnosis is effective by itself, as there is no clear biological distinction between hypnosis and wakefulness; people who are hypnotized do not elicit the same type of brain waves that people do while they're asleep
Occasionally, if there is enough evidence missing to convict a suspect in a crime or bring that suspect in for a trial, law enforcement will attempt hypnosis in some cases to try and get a witness to remember more than they can consciously. But hypnosis does not improve memory. It does increase the amount of information the witness can recall, but much of it is inaccurate and can lead to wrongful persecution or many more issues with the case.
Personally, I've always been the type of skeptic to reject hypnosis as a medical, recollection, or any other kind of tool. Our text provides a good explanation of theories as well as myths though, and it's interesting to note that it does have respect in the psychological world although it's not widely accepted.
Here's a link to a video about Suggestibility Tests, what hypnotists use before shows to select performers: