Franz Anton Mesmer (1734–1815) was an Austrian doctor who believed that all living bodies were filled with magnetic energy. In his practice, Mesmer passed magnets over the bodies of his patients while telling them their physical and psychological problems would disappear. The patients frequently lapsed into a trancelike state (they were said to be “mesmerized”) and reported feeling better when they awoke (Hammond, 2008). 1
Although subsequent research testing the effectiveness of Mesmer’s techniques did not find any long-lasting improvements in his patients, the idea that people’s experiences and behaviors could be changed through the power of suggestion has remained important in psychology. James Braid, a Scottish physician, coined the term hypnosis in 1843, basing it on the Greek word for sleep(Callahan, 1997). 2
Hypnosis is a trance-like state of consciousness, usually induced by a procedure known as hypnotic induction, which consists of heightened suggestibility, deep relaxation, and intense focus(Nash & Barnier, 2008). 3 Hypnosis became famous in part through its use by Sigmund Freud in an attempt to make unconscious desires and emotions conscious and thus able to be considered and confronted (Baker & Nash, 2008). 4
Because hypnosis is based on the power of suggestion, and because some people are more suggestible than others, these people are more easily hypnotized. Hilgard (1965) 5 found that about 20% of the participants he tested were entirely unsusceptible to hypnosis, whereas about 15% were highly responsive to it. The best participants for hypnosis are people who are willing or eager to be hypnotized, who are able to focus their attention and block out peripheral awareness, who are open to new experiences, and who are capable of fantasy (Spiegel, Greenleaf, & Spiegel, 2005). 6
People who want to become hypnotized are motivated to be good subjects, to be open to suggestions by the hypnotist, and to fulfill the role of a hypnotized person as they perceive it (Spanos, 1991). 7 The hypnotized state results from a combination of conformity, relaxation, obedience, and suggestion (Fassler, Lynn, & Knox, 2008). 8 This does not necessarily indicate that hypnotized people are “faking” or lying about being hypnotized. Kinnunen, Zamansky, and Block (1994) 9 used measures of skin conductance (which indicates emotional response by measuring perspiration, and therefore renders it a reliable indicator of deception) to test whether hypnotized people were lying about having been hypnotized. Their results suggested that almost 90% of their supposedly hypnotized subjects truly believed that they had been hypnotized.
One common misconception about hypnosis is that the hypnotist is able to “take control” of hypnotized patients and thus can command them to engage in behaviors against their will. Although hypnotized people are suggestible (Jamieson & Hasegawa, 2007), 10 they nevertheless retain awareness and control of their behavior and are able to refuse to comply with the hypnotist’s suggestions if they so choose (Kirsch & Braffman, 2001). 11 In fact, people who have not been hypnotized are often just as suggestible as those who have been (Orne & Evans, 1965). 12
Another common belief is that hypnotists can lead people to forget the things that happened to them while they were hypnotized. Hilgard and Cooper (1965) 13 investigated this question and found that they could lead people who were very highly susceptible through hypnosis to show at least some signs of posthypnotic amnesia (e.g., forgetting where they had learned information that had been told to them while they were under hypnosis), but that this effect was not strong or common.
Some hypnotists have tried to use hypnosis to help people remember events, such as childhood experiences or details of crime scenes, that they have forgotten or repressed. The idea is that some memories have been stored but can no longer be retrieved, and that hypnosis can aid in the retrieval process. But research finds that this is not successful: People who are hypnotized and then asked to relive their childhood act like children, but they do not accurately recall the things that occurred to them in their own childhood (Silverman & Retzlaff, 1986). 14 Furthermore, the suggestibility produced through hypnosis may lead people to erroneously recall experiences that they did not have (Newman & Baumeister, 1996). 15 Many states and jurisdictions have therefore banned the use of hypnosis in criminal trials because the “evidence” recovered through hypnosis is likely to be fabricated and inaccurate.
Hypnosis is also frequently used to attempt to change unwanted behaviors, such as to reduce smoking, overeating, and alcohol abuse. The effectiveness of hypnosis in these areas is controversial, although at least some successes have been reported. Kirsch, Montgomery, and Sapirstein (1995) 16 found that that adding hypnosis to other forms of therapies increased the effectiveness of the treatment, and Elkins and Perfect (2008) 17 reported that hypnosis was useful in helping people stop smoking. Hypnosis is also effective in improving the experiences of patients who are experiencing anxiety disorders, such as PTSD (Cardena, 2000; Montgomery, David, Winkel, Silverstein, & Bovbjerg, 2002), 18 and for reducing pain (Montgomery, DuHamel, & Redd, 2000; Paterson & Jensen, 2003). 19