Hypnosis is a natural state of attentive, focused concentration. As such, most individuals are able to experience trance-like states at different times in their daily lives. An example is the alteration of awareness experienced by some persons as they concentrate in-tently on a movie or a play while disconnecting from awareness of the surrounding environment. Depending on the degree of natural ability to enter a trance state (hypnotic capacity or hypnotizabil-ity), a given subject will require more or less help to enter and use his or her hypnotic capacity. That is, highly hypnotizable individ-uals enter trance states with ease, on many occasions even without being fully aware of it. Individuals with low hypnotizability re-quire more direction or help from the therapist who facilitates the trance experience. High hypnotic capacity may actually become a liability to patients who are unaware of their hypnotic capacity or of their unconscious use of this mechanism, as is the case of individuals suffering from a dissociative disorder. Even when we do not intend to use hypnosis formally, we must remember that the ability to enter a trance state is widely and naturally distributed throughout the normal population. Thus, some of our patients may be experiencing trance states even without our planning.
In 1960, the American Medical Association and the American Psychiatric Association (APA) officially recognized hypnosis as a legitimate therapeutic tool. At present, the uses of hypnosis in clinical and investigational areas continue to grow, as does research on the neuropsychological mechanisms involved in the hypnotic process.
Hypnosis is a psychophysiological state of attentive, receptive concentration, with a relative suspension of peripheral aware-ness. Hypnotic phenomena occur spontaneously, and the altera-tion of consciousness that hypnotized individuals experience has a variety of therapeutic applications. The hypnotic experience may be understood as involving three main factors (Table 72.1).