Hypnosis in Contemporary Medicine
2005; Elsevier BV; Volume: 80; Issue: 4 Linguagem: Inglês
10.4065/80.4.511
ISSN1942-5546
Autores Tópico(s)Neurology and Historical Studies
ResumoHypnosis became popular as a treatment for medical conditions in the late 1700s when effective pharmaceutical and surgical treatment options were limited. To determine whether hypnosis has a role in contemporary medicine, relevant trials and a few case reports are reviewed. Despite substantial variation in techniques among the numerous reports, patients treated with hypnosis experienced substantial benefits for many different medical conditions. An expanded role for hypnosis and a larger study of techniques appear to be indicated. Hypnosis became popular as a treatment for medical conditions in the late 1700s when effective pharmaceutical and surgical treatment options were limited. To determine whether hypnosis has a role in contemporary medicine, relevant trials and a few case reports are reviewed. Despite substantial variation in techniques among the numerous reports, patients treated with hypnosis experienced substantial benefits for many different medical conditions. An expanded role for hypnosis and a larger study of techniques appear to be indicated. As alternative treatments for medical conditions become popular, contemporary medicine is being challenged to take a more integrative approach. The National Institutes of Health is supporting clinical trials of complementary and alternative medicine, which includes hypnosis. To determine whether hypnosis has a role in presentday medicine, this review evaluates relevant clinical trials involving hypnosis. Some important case reports and reviews are included to give insight into the current and past practice of hypnosis in medicine by professionals. This review pertains to the use of hypnosis for conditions not believed to be primarily psychological (eg, depression, anxiety, attention deficit disorders, and phobias), although the potential for a psychological basis exists for many of these conditions. The intent of this review is to stimulate greater interest in and understanding of the art and science of hypnosis. The studies reviewed herein were identified by searching the MEDLINE database for articles published between 1966 and 2004; the key words hypnosis, hypnotism, and hypnotherapy were used, as were the specific conditions studied. All studies relevant and applicable to the treatment of the conditions evaluated were reviewed critically and were subsequently included if their conclusions were supported by the data given. Results of controlled trials, review articles, and case reports are presented. In this review, P<.05 was considered statistically significant unless otherwise indicated. Although no consensus definition of hypnosis exists, the studies reviewed indicate that hypnosis involves the induction of a state of mind in which a person's normal critical or skeptical nature is bypassed, allowing for acceptance of suggestions (Table 1). This state of heightened receptivity for suggestions (induction) is developed with the cooperation of the patient and is followed by the delivery of positive suggestions.1Fromm E Significant developments in clinical hypnosis during the past 25years.Int J Clin Exp Hypn. 1987; 35: 215-230Crossref Google Scholar, 2Elman D Hypnotherapy. Westwood Publishing Co, Glendale, Calif1964Google Scholar Hypnosis is also described as an "attentive, receptive focal concentration," with the trance state being a "normal activity of a normal mind," which occurs regularly, as when reading an absorbing book, watching an engrossing movie, daydreaming, or performing monotonous activity.3Spiegel H Greenleaf M Spiegel D Hypnosis.in: Sadock BJ Sadock VA 7th ed. Kaplan & Sadock's Comprehensive Textbook of Psychiatry. Vol 2. Lippincott Williams & Wilkins, Philadelphia, Pa2000: 2138-2146Google Scholar A common assumption is that, during hypnosis, the subconscious mind is in a suggestible state while the conscious mind is distracted or guided to become dormant.Table 1Characteristics of Hypnosis and a Hypnosis Session Hypnosis is a state of mind that occurs naturally or is established by compliance with instructions and is characterized by Focused attentionHeightened receptivity for suggestionsA bypass of the normal critical nature of the mindDelivery of acceptable suggestionsA hypnosis session consists of An explanation of the process and consentInduction of the trance stateDeepening of the tranceAssessment for adequacy of the tranceHypnoanalysis—an investigative step (if necessary)Delivery of acceptable suggestionsEmergence from the trance state Open table in a new tab Hypnosis may be compared with meditation, which generally is considered to involve a quieting of the mind. Meditation may be self-directed. If suggestions are given to achieve a desired effect, meditation may qualify as hypnosis depending on the state achieved, particularly because hypnosis can occur naturally (ie, without formal induction). No attempt is made herein to explain the mechanism of hypnosis for causing the intended changes as a result of the suggestions given. If positive suggestions for change are accepted by the mind, any physiological changes that follow defy explanation by contemporary medicine, although complex explanations have been proposed.4Rossi EL The Psychobiology of Mind-Body Healing: New Concepts of Therapeutic Hypnosis. Rev ed. WW Norton, New York, NY1993Google Scholar Various methods have been used to determine whether hypnosis is a separate state, distinct from sleep, or if the patient is simply complying with the practitioner's instructions.3Spiegel H Greenleaf M Spiegel D Hypnosis.in: Sadock BJ Sadock VA 7th ed. Kaplan & Sadock's Comprehensive Textbook of Psychiatry. Vol 2. Lippincott Williams & Wilkins, Philadelphia, Pa2000: 2138-2146Google Scholar Volunteers in whom hypnosis was induced were evaluated by positron emission tomography (PET). When subjects were given the suggestion to see color, the color perception areas of their cerebral hemispheres were activated whether they were looking at color or black-and-white patterns. When subjects were given the suggestion to see black and white, the color perception areas of the brain showed decreased activity regardless of what the subjects were viewing. This implies that hypnosis is not a process of simply following instructions but actually involves a change in the brain's perception.5Kosslyn SM Thompson WL Costantini-Ferrando MF Alpert NM Spiegel D Hypnotic visual illusion alters color processing in the brain.Am J Psychiatry. 2000; 157: 1279-1284Crossref PubMed Scopus (155) Google Scholar Studies have used other methods, such as electrodermal skin conductance, to evaluate whether patients in whom hypnosis was induced were "lying" or simply complying with instructions.6Kinnunen T Zamansky HS Block ML Is the hypnotized subject lying?.J Abnorm Psychol. 1994; 103: 184-191Crossref Scopus (11) Google Scholar, 7Kinnunen T Zamansky HS Nordstrom BL Is the hypnotized subject complying?.Int J Clin Exp Hypn. 2001; 49: 83-94Crossref Google Scholar Unpleasant sensations were noted on PET to cause activity in the anterior cingulate cortex. Hypnosis induced before painful stimuli caused a decrease in the subjective and objective perception of the pain as noted on the scans.8Faymonville ME Laureys S Degueldre C et al.Neural mechanisms of antinociceptive effects of hypnosis.Anesthesiology. 2000; 92: 1257-1267Crossref PubMed Google Scholar Another study using PET in hypnotized persons showed activation of a region in the right anterior cingulate cortex (Brodmann area 32), an area activated when sound is heard or when sound is suggested in hypnosis but not when sound is simply imagined. This implies that the mind registered the hypnotic hallucination as if it were real.9Szechtman H Woody E Bowers KS Nahmias C Where the imaginal appears real: a positron emission tomography study of auditory hallucinations.Proc Natl Acad Sci U S A. 1998; 95: 1956-1960Crossref Scopus (129) Google Scholar Other studies using PET support the occurrence of distinct changes in the brain with hypnosis.10Rainville P Hofbauer RK Bushnell MC Duncan GH Price DD Hypnosis modulates activity in brain structures involved in the regulation of consciousness.J Cogn Neurosci. 2002; 14: 887-901Crossref Scopus (127) Google Scholar By using electroencephalography, changes were seen during hypnosis that could not be evoked by waking imagination.11Jensen SM Barabasz A Barabasz M Warner D EEG P300 event-related markers of hypnosis.Am J Clin Hypn. 2001; 44: 127-139Crossref Google Scholar Hypnosis does not act as a placebo (administering a pharmacologically inert substance).12McGlashan TH Evans FJ Orne MT The nature of hypnotic analgesia and placebo response to experimental pain.Psychosom Med. 1969; 31: 227-246PubMed Google Scholar Studies using hypnosis for anesthesia indicate that pain relief from hypnosis is different from a placebo effect with evidence that the pain is not perceived rather than simply experienced with greater tolerance.13Zachariae R Bjerring P The effect of hypnotically induced analgesia on flare reaction of the cutaneous histamine prick test.Arch Dermatol Res. 1990; 282: 539-543Crossref PubMed Scopus (23) Google Scholar, 14Spiegel D Bierre P Rootenberg J Hypnotic alteration of somatosensory perception.Am J Psychiatry. 1989; 146: 749-754PubMed Google Scholar, 15Patterson DR Jensen MP Hypnosis and clinical pain.Psychol Bull. 2003; 129: 495-521Crossref PubMed Scopus (139) Google Scholar Hypnosis is not a state of sleep.16Tasman A Kay J Lieberman JA Psychiatry. Vol 2. WB Saunders Co, Philadelphia, Pa1997: 1478-1499Google Scholar Relaxation generally is believed to be a part of hypnosis, but it need not be. Volunteers underwent hypnotic induction with use of either the traditional method involving eye closure, relaxation, and drowsiness encouraged by suggestion or an active, alert method involving riding a stationary bicycle while receiving suggestions for alertness and activity. Equally receptive trance states were achieved by the relaxation and alert methods, and examples were presented of other active, alert trance states.17Banyai EI Hilgard ER A comparison of active-alert hypnotic induction with traditional relaxation induction.J Abnorm Psychol. 1976; 85: 218-224Crossref Google Scholar Of note, hypnotized patients may experience considerable anxiety and other emotions while reliving an event with age regression without coming out of the trance state.18MacHovec F Hypnosis complications, risk factors, and prevention.Am J Clin Hypn. 1988; 31: 40-49Crossref Google Scholar Age regression, inducing a person through hypnosis to relive events that occurred earlier in life, is believed to differ from enhancement of memory, but scientific evidence for this assertion is limited. Age regression may be helpful to treat conditions in which an adverse behavior is believed to be based on a past event; however, its validity is controversial. The process of regression may generate strong emotions and can possibly alter a memory or create a false memory. Studies about the use of age regression have reported the development of infantile neurologic reflexes on regression to infancy, age-specific handwriting and vocabularies on regression to childhood, and knowledge of the appropriate day of the week of events in the period to which the person was regressed.19Gidro-Frank L Bowersbuch MK A study of the plantar response in hypnotic age regression.J Nerv Ment Dis. 1948; 107: 443-458Crossref Google Scholar, 20LeCron LM A study of age regression under hypnosis.in: LeCron LM Experimental Hypnosis: A Symposium of Articles on Research by Many of the World's Leading Authorities. Macmillan, New York, NY1952: 155-174Google Scholar The era of modern hypnotism began with the Austrian physician Franz Anton Mesmer, who is said to have brought animal magnetism (the term for hypnosis at that time) to France in 1778. Because many people were seeking treatment from Mesmer and his colleagues, King Louis XVI of France commissioned Benjamin Franklin and others to investigate the practice. After extensive testing, the commission discredited Mesmer, indicating in their report that any medical benefit was not from magnetism, as publicized, and that mesmerism involved only "imagination, imitation, and touch." One account indicates that Thomas Jefferson obtained copies of the report to help prevent the spread of mesmerism to America.21McConkey KM Perry C Benjamin Franklin and mesmerism, revisited.Int J Clin Exp Hypn. 2002; 50: 320-331Crossref Google Scholar, 22Forrest DW Hypnotism: A History. Penguin, London, England1999Google Scholar This setback for hypnosis led to a deeper, more covert evaluation of the process. James Braid, using eye fixation techniques, was able to produce a trance state and later discovered the importance of adding suggestions. He is credited with introducing the term hypnotism, although he favored monoideism because he realized that the state differs from sleep.3Spiegel H Greenleaf M Spiegel D Hypnosis.in: Sadock BJ Sadock VA 7th ed. Kaplan & Sadock's Comprehensive Textbook of Psychiatry. Vol 2. Lippincott Williams & Wilkins, Philadelphia, Pa2000: 2138-2146Google Scholar In the 19th century, the English surgeon John Elliotson and the Scottish surgeon James Esdaile performed hundreds of surgical procedures with use of hypnosis for anesthesia and with extremely low morbidity rates for the times.22Forrest DW Hypnotism: A History. Penguin, London, England1999Google Scholar Almost simultaneously with the reports of success with hypnosis, ether and chloroform became popular and displaced the use of hypnosis for anesthesia in surgery.23Marmer MJ Present applications of hypnosis in anesthesiology.West J Surg Obstet Gynecol. 1961; 69: 260-263Google Scholar, 24Blankfield RP Suggestion, relaxation, and hypnosis as adjuncts in the care of surgery patients: a review of the literature.Am J Clin Hypn. 1991; 33: 172-186Crossref Google Scholar Twentieth-century hypnosis was influenced by the contrasting techniques of indirect suggestion intermixed with psychoanalysis promoted by Milton H. Erickson and of direct suggestion and induction of a deep trance state for age regression espoused by others.1Fromm E Significant developments in clinical hypnosis during the past 25years.Int J Clin Exp Hypn. 1987; 35: 215-230Crossref Google Scholar, 2Elman D Hypnotherapy. Westwood Publishing Co, Glendale, Calif1964Google Scholar, 22Forrest DW Hypnotism: A History. Penguin, London, England1999Google Scholar Acceptance of hypnosis in medicine has evolved slowly. In 1847, the Roman Catholic Church indicated acceptance of hypnosis, noting that hypnosis was not morally forbidden, and in 1956, Pope Pius XII noted its use for childbirth and indicated the need for proper precautions as for other forms of medical treatment. Other religions (with exceptions) have shown acceptance, with ministers of different faiths trained in and using hypnosis in their practices.25Durbin PG Kissing Frogs: Practical Uses of Hypnotherapy. 2nd ed. Kendall/Hunt Publishing Co, Dubuque, Iowa1998Google Scholar In 1958, the American Medical Association (AMA) published and approved a report from a 2-year study by the Council on Mental Health. The report indicated that there can be "definite and proper uses of hypnosis in medical and dental practice" and recommended the establishment of "necessary training facilities" in the United States.26Council on Mental Health Medical use of hypnosis.JAMA. 1958; 168: 186-189Crossref Google Scholar The British Medical Association had issued its report on hypnosis in the British Medical Journal in 1955, with which the AMA's Council on Mental Health indicated "essential agreement."3Spiegel H Greenleaf M Spiegel D Hypnosis.in: Sadock BJ Sadock VA 7th ed. Kaplan & Sadock's Comprehensive Textbook of Psychiatry. Vol 2. Lippincott Williams & Wilkins, Philadelphia, Pa2000: 2138-2146Google Scholar, 26Council on Mental Health Medical use of hypnosis.JAMA. 1958; 168: 186-189Crossref Google Scholar The American Psychiatric Association, in a position statement approved by the Council of the Association in 1961, indicated that "hypnosis has definite application in the various fields of medicine" and that physicians would be seeking psychiatrists for training in hypnosis.27American Psychiatric Association Regarding Hypnosis Position Statement [approved by the Council February 15, 1961].Available at: www.psych.org/public_info/libr_publ/position.cfmGoogle Scholar A National Institutes of Health panel issued a statement published by the AMA in 1996 indicating that there was "strong evidence for the use of hypnosis in alleviating pain associated with cancer."28NIH Technology Assessment Panel on Integration of Behavioral and Relaxation Approaches into the Treatment of Chronic Pain and Insomnia Integration of behavioral and relaxation approaches into the treatment of chronic pain and insomnia.JAMA. 1996; 276: 313-318Crossref Google Scholar A review of the literature in the late 1980s documented a few cases of patients who displayed "unanticipated" adverse behavior after hypnosis.18MacHovec F Hypnosis complications, risk factors, and prevention.Am J Clin Hypn. 1988; 31: 40-49Crossref Google Scholar Adverse reactions or hypnotic complications consisted of "unexpected, unwanted thoughts, feelings or behaviors during or after hypnosis which are inconsistent with agreed goals and interfere with the hypnotic process by impairing optimal mental function." The most common suspected adverse reactions included drowsiness, dizziness, stiffness, headaches, anxiety, and, occasionally, more serious reactions such as symptom substitution and masking of organic disorders. These adverse reactions were attributed to deficiencies in the hypnotist's techniques, such as not realizing that suggestions in hypnosis are accepted literally, bringing the patient too rapidly out of trance, using age regression inappropriately, not dispelling preconceived expectations of negative consequences of hypnosis before initiating the session, or not prescreening for certain psychopathology.18MacHovec F Hypnosis complications, risk factors, and prevention.Am J Clin Hypn. 1988; 31: 40-49Crossref Google Scholar A more recent review indicated that hypnosis is associated with a risk of adverse effects, including headache, dizziness, nausea, anxiety, or panic, at levels that might occur in other test or experimental settings without hypnosis. A prehypnosis discussion session with the patient was advocated.29Lynn SJ Martin DJ Frauman DC Does hypnosis pose special risks for negative effects? a master class commentary.Int J Clin Exp Hypn. 1996; 44: 7-19Crossref Google Scholar It has been argued that informed consent is not needed before casual or brief techniques involving helpful semantics since the use of careless and harmful comments from health care workers has no such prerequisite.30Bierman SF Hypnosis in the emergency department.Am J Emerg Med. 1989; 7: 238-242Abstract Full Text PDF Google Scholar Hypnosis generally is considered a "benign process" with "few contraindications"; however, pseudomemories can be created if leading questions are asked during the investigative phase of hypnosis.16Tasman A Kay J Lieberman JA Psychiatry. Vol 2. WB Saunders Co, Philadelphia, Pa1997: 1478-1499Google Scholar Evaluation of clinical trials of hypnosis is complicated by the nature of hypnosis. The gold standard of a randomized, double-blind, controlled trial is virtually impossible because cooperation and rapport between patient and therapist are needed to achieve a receptive trance state. The few hypnosis trials that were blinded involved suggestions delivered by audiotape during surgery while patients were under general anesthesia (assumed to be a hypnoticlike state). Evaluation of these trials is limited by the lack of standardized techniques for hypnotic induction, evaluation of the level of trance, delivery of suggestions, or number and length of sessions. Although the state of hypnosis involves increased receptivity to acceptable suggestions, the methods of delivering the suggestions vary substantially. In some trials, researchers gave suggestions only for relaxation or no suggestions at all. In other trials, researchers indirectly suggested that patients allow a feeling or imagination rather than directing them to have a certain feeling, which relied on patients understanding the intention. In some studies, researchers gave suggestions only to distract the mind during an otherwise uncomfortable procedure or condition. Thus, it is reasonable to consider the appropriateness of judging hypnosis by the best or worst results, with use of averaging, or by meta-analyses.31Montgomery GH DuHamel KN Redd WH A meta-analysis of hypnotically induced analgesia: how effective is hypnosis?.Int J Clin Exp Hypn. 2000; 48: 138-153Crossref PubMed Google Scholar, 32Montgomery GH David D Winkel G Silverstein JH Bovbjerg DH The effectiveness of adjunctive hypnosis with surgical patients: a meta-analysis.Anesth Analg. 2002; 94: 1639-1645Google Scholar, 33Viswesvaran C Schmidt FL A meta-analytic comparison of the effectiveness of smoking cessation methods.J Appl Psychol. 1992; 77: 554-561Crossref Google Scholar, 34Bongartz W Flammer E Schwonke R Efficiency of hypnosis: a meta-analytic study [in German].Psychotherapeutics. 2002; 47: 67-76Crossref Scopus (11) Google Scholar Indeed, although better methods would be expected to achieve better results, many trials gave too few details about technique to allow comparison. If the most efficacious hypnosis techniques were known, a more representative review of the state of the art may include only trials using such techniques. A deficiency of the trials reviewed is the lack of randomization of patient and practitioner variables that may affect outcome. Patient characteristics such as fear, attentiveness, interest, expectation, suggestibility, motivation, desire, and belief in hypnosis may alter outcomes. According to the literature, vital practitioner characteristics include training and experience and the ability to induce trance, to properly word suggestions, and to establish the necessary states of expectancy, rapport, and motivation (if not already present).1Fromm E Significant developments in clinical hypnosis during the past 25years.Int J Clin Exp Hypn. 1987; 35: 215-230Crossref Google Scholar, 24Blankfield RP Suggestion, relaxation, and hypnosis as adjuncts in the care of surgery patients: a review of the literature.Am J Clin Hypn. 1991; 33: 172-186Crossref Google Scholar, 35Baker EL The state of the art of clinical hypnosis.Int J Clin Exp Hypn. 1987; 35: 203-214Crossref Google Scholar Furthermore, results from clinical trials may not accurately estimate the effectiveness achievable in an office setting with willing, expectant patients. In clinical trials, many patients are likely to be unwilling, unmotivated, or skeptical about hypnosis. Hypnosis appears to be "particularly useful and yields better results when it is specifically requested by the patient."16Tasman A Kay J Lieberman JA Psychiatry. Vol 2. WB Saunders Co, Philadelphia, Pa1997: 1478-1499Google Scholar Consequently, clinical trials may underestimate the benefits of hypnosis compared with those obtainable by a proficient, experienced hypnotist. Allergic or hypersensitivity reactions usually are not believed to be psychosomatic and thus are generally considered as unable to be influenced by suggestion. These highly complex reactions involve IgE antibodies, activation of mast cells and basophils, and release of chemical mediators of inflammatory and immune responses. Some early literature suggested that many allergies might have an emotional basis and thus be treatable by hypnosis.2Elman D Hypnotherapy. Westwood Publishing Co, Glendale, Calif1964Google Scholar Subsequent studies have shown that hypnosis may alter the body's physiological response to various stimuli. In a study of 18 volunteers selected for their hypnotizability, immediate-type hypersensitivity reactions were suppressed in 8 of the 12 patients given brief direct suggestions in hypnosis.36Black S Inhibition of immediate-type hypersensitivity response by direct suggestion under hypnosis.Br Med J. 1963; 1: 925-929Crossref PubMed Google Scholar In another trial, hypnotic suggestions for relaxation reduced helper/inducer cell percentages, helper/suppressor cell ratios, and natural killer cell activity compared with prehypnosis baseline values.37Kiecolt-Glaser JK Glaser R Strain EC et al.Modulation of cellular immunity in medical students.J Behav Med. 1986; 9: 5-21Crossref PubMed Scopus (152) Google Scholar Other researchers have shown the positive effects of social support on natural killer cell activity and cortisol levels and the adverse effects of stress in patients with cancer, which has implications for cancer progression.38Spiegel D Sephton SE Psychoneuroimmune and endocrine pathways in cancer: effects of stress and support.Semin Clin Neuropsychiatry. 2001; 6: 252-265Crossref Google Scholar Skin prick testing for type I (immediate) hypersensitivity and testing with purified protein derivative (in persons vaccinated previously for tuberculosis) for type IV hypersensitivity were performed before and after hypnosis.39Zachariae R Bjerring P Arendt-Nielsen L Modulation of type I immediate and type IV delayed immunoreactivity using direct suggestion and guided imagery during hypnosis.Allergy. 1989; 44: 537-542Crossref PubMed Google Scholar Patients in the hypnosis group (but not the control group) who were given suggestions for increasing or decreasing skin reactions were able to increase the flare and wheal reactions on 1 arm and decrease the flare reaction on the other, with a significant difference between the 2 arms. The same authors later studied volunteers selected for their high hypnotizability and evaluated their reactions to histamine pin pricks and laser-induced burn pain.13Zachariae R Bjerring P The effect of hypnotically induced analgesia on flare reaction of the cutaneous histamine prick test.Arch Dermatol Res. 1990; 282: 539-543Crossref PubMed Scopus (23) Google Scholar Hypnosis was associated with a significant reduction in both pain and flare reactions. Numerous studies have shown benefits of hypnosis for pain relief (Table 240Goldstein A Hilgard ER Failure of the opiate antagonist naloxone to modify hypnotic analgesia.Proc Natl Acad Sci U S A. 1975; 72: 2041-2043Crossref Google Scholar, 41Spiegel D Albert LH Naloxone fails to reverse hypnotic alleviation of chronic pain.Psychopharmacology (Berl). 1983; 81: 140-143Crossref Google Scholar, 42Stern JA Brown M Ulett GA Sletten I A comparison of hypnosis, acupuncture, morphine, valium, aspirin, and placebo in the management of experimentally induced pain.Ann N Y Acad Sci. 1977; 296: 175-193Crossref Google Scholar, 43Lu DP Lu GP Kleinman L Acupuncture and clinical hypnosis for facial and head and neck pain: a single crossover comparison.Am J Clin Hypn. 2001; 44: 141-148Crossref Google Scholar, 44Wakeman JR Kaplan JZ An experimental study of hypnosis in painful burns.Am J Clin Hypn. 1978; 21: 3-12Crossref Google Scholar, 45Patterson DR Everett JJ Burns GL Marvin JA Hypnosis for the treatment of burn pain.J Consult Clin Psychol. 1992; 60: 713-717Crossref Google Scholar, 46Simon EP Lewis DM Medical hypnosis for temporomandibular disorders: treatment efficacy and medical utilization outcome.Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2000; 90: 54-63Abstract Full Text Full Text PDF PubMed Scopus (33) Google Scholar). In a study with experimental pain stimulation by pin prick and laser heat, direct suggestions in hypnosis resulted in a significant decrease in pain, measured subjectively and objectively by means of pain-related brain potentials.13Zachariae R Bjerring P The effect of hypnotically induced analgesia on flare reaction of the cutaneous histamine prick test.Arch Dermatol Res. 1990; 282: 539-543Crossref PubMed Scopus (23) Google Scholar In another study, highly hypnotizable (based on susceptibility testing) volunteers given painful electrical stimulation were able to increase or decrease their perception of pain as noted on event-related somatosensory potentials.14Spiegel D Bierre P Rootenberg J Hypnotic alteration of somatosensory perception.Am J Psychiatry. 1989; 146: 749-754PubMed Google ScholarTable 2Comparison of Clinical Trials of Hypnosis for Analgesia*NA = not applicable; NR = not reported.TrialReferenceType of painTesting for hypnotizabilityControlledRandomizedNo. of subjects/patientsRefractory conditionSelf-hypnosis or home tapes?‡Patients encouraged to use either self-hypnosis or audiotapes at home (usually daily).TherapyNo. of sessionsFollow-upGoldstein & Hilgard,40Goldstein A Hilgard ER Failure of the opiate antagonist naloxone to modify hypnotic analgesia.Proc Natl Acad Sci U S A. 1975; 72: 2041-2043Crossref Google Scholar 1975Induced by tourniquetYesOwn†Patients served as their own controls.No3NANoIndividual1NASpiegel & Albert,41Spiegel D Albert LH Naloxone fails to reverse hypnotic alleviation of chronic pain.Psychopharmacology (Berl). 1983; 81: 140-143Crossref Google Scholar 1983NeuropathicYesOwn†Patients served as their own controls.Doubleblind, crossover6NoYesNRNRNAStern et al,42Stern JA Brown M Ulett GA Sletten I A comparison of hypnosis, acupuncture, morphine, valium, aspirin, and placebo in the management of experimentally induced pain.Ann N Y Acad Sci. 1977; 296: 175-193Crossref Google Scholar 1977Induced by ice water or tourniquetYesOwn†Patients served as their own controls.No20NANoIndividual1NALu et al,43Lu DP Lu GP Kleinman L Acupuncture and clinical hypnosis for facial and head and neck pain: a sing
Referência(s)