Hypnotic Analgesia Suggestions Research Articles

Comparison of Hypnotic Suggestion and Transcranial Direct-Current Stimulation Effects on Pain Perception and the Descending Pain Modulating System: A Crossover Randomized Clinical Trial.

Objectives: This paper aims to determine if hypnotic analgesia suggestion and transcranial direct-current stimulation (tDCS) have a differential effect on pain perception. We hypothesized that transcranial direct-current stimulation would be more effective than hypnotic analgesia suggestion at changing the descending pain modulating system, whereas the hypnotic suggestion would have a greater effect in quantitative sensory testing.Design: This is a randomized, double blind and crossover trial.Settings: All stages of this clinical trial were performed at the Laboratory of Pain and Neuromodulation of the Hospital de Clínicas de Porto Alegre.Subjects: Were included 24 healthy females aged from 18 to 45 years old, with a high susceptibility to hypnosis, according to the Waterloo-Stanford Group Scale of Hypnotic Susceptibility, Form C (15).Methods: The subjects received a random and crossover transcranial direct-current stimulation over the dorsolateral prefrontal cortex (2 mA for 20 min) and hypnotic analgesia (20 min).Results: Only hypnotic suggestion produced changes that are statistically significant from pre- to post-intervention in the following outcomes measures: heat pain threshold, heat pain tolerance, cold pressure test, and serum brain-derivate-neurotrophic-factor. The analysis showed a significant main effect for treatment (F = 4.32; P = 0.04) when we compared the delta-(Δ) of conditioned pain modulation task between the transcranial direct-current stimulation and hypnotic suggestion groups. Also, the change in the brain-derivate-neurotrophic-factor was positively correlated with the conditioned pain modulation task.Conclusion: The results confirm a differential effect between hypnotic suggestion and transcranial direct-current stimulation on the pain measures. They suggest that the impact of the interventions has differential neural mechanisms, since the hypnotic suggestion improved pain perception, whereas the transcranial direct-current stimulation increased inhibition of the descending pain modulating system.Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT03744897.Perspective: These findings highlight the effect of hypnotic suggestion on contra-regulating mechanisms involved in pain perception, while the transcranial direct-current stimulation increased inhibition of the descending pain modulating system. They could help clinicians comprehend the mechanisms involved in hypnotic analgesia and transcranial direct-current stimulation and thus may contribute to pain and disability management.

Somatosensory Sensitivity in Patients With Persistent Idiopathic Orofacial Pain Is Associated With Pain Relief From Hypnosis and Relaxation

In a recent study hypnosis has been found to relieve persistent idiopathic orofacial pain. Quantitative sensory testing (QST) is widely used to evaluate somatosensory sensitivity, which has been suggested as a possible predictor of management outcome. The objectives of this study were to examine: (1) possible associations between clinical pain relief and baseline somatosensory sensitivity and (2) the effect of hypnosis management on QST parameters. Forty-one patients with persistent idiopathic orofacial pain completed this randomized controlled study in 1 of 2 groups: hypnosis (hypnotic analgesia suggestions) or control (relaxation). QST at 2 intraoral (pain region and contralateral mirror image region) and 3 extraoral (hand and both cheeks) sites was performed at baseline and after the hypnosis/control management, together with pressure pain thresholds and pressure pain tolerance thresholds determined bilaterally at the masseter and temporalis muscles, the temporomandibular joints, and the third finger. Degree of pain relief was negatively correlated with a summary statistic of baseline somatosensory sensitivity (summed z-score), that is, high baseline somatosensory sensitivity was associated with low pain relief (r=-0.372, P=0.020). Hypnosis had no major effect on any QST measure compared with relaxation (P>0.063). High pain sensitivity at baseline may predict poor pain management outcome. In addition, despite clear clinical pain relief, hypnosis did not significantly or specifically influence somatosensory sensitivity. Future studies should further explore QST measures as possible predictors of different management response in orofacial pain conditions.

The predictive utility of hypnotizability: The change in suggestibility produced by hypnosis.

The predictive utility of hypnotizability, conceptualized as the change in suggestibility produced by a hypnotic induction, was investigated in the suggested reduction of experimental pain. One hundred and seventy-three participants were assessed for nonhypnotic imaginative suggestibility. Thereafter, participants experienced hypnotic and nonhypnotic imaginative analgesia suggestions, counterbalanced for order. Hypnotic suggestibility was then assessed. Hypnotizability, operationalized as hypnotic suggestibility with imaginative suggestibility statistically controlled (Braffman & Kirsch, 1999), predicted intraindividual differences in responding to the hypnotic and imaginative analgesia suggestions. Higher hypnotizability was associated with relatively greater response to the hypnotic analgesia suggestion than to the imaginative analgesia suggestion. Operationalized in this way, hypnotizability may be a useful predictor of the effect of adding a hypnotic induction to a specific imaginative suggestion.

Response expectancies: a psychological mechanism of suggested and placebo analgesia

AbstractResponse expectancies, or the expectation of one's own non‐volitional reactions to situational cues, are hypothesized to be a psychological mechanism of both hypnotic and placebo responding (Kirsch, 1990). In this study, response expectancies were evaluated as a mediator of suggested and placebo analgesia using Baron and Kenny's (1986) classic method of testing mediation. One hundred and seventy‐two volunteers were randomly assigned to hypnotic analgesia suggestion, imaginative analgesia suggestion, placebo analgesia, or no‐treatment control conditions. The hypnotic, imaginative and placebo treatments were more effective than the no‐treatment control condition in relieving finger pressure pain. The hypnotic treatment was also more effective than the placebo. Each of the three treatments was partially mediated by response expectancies, although the percentage of mediation varied across the hypnotic (25%), imaginative (29%) and placebo (41%) conditions. The findings support the position that response expectancies are one of the major psychological mechanisms of suggested and placebo analgesia. Copyright © 2009 British Society of Experimental & Clinical Hypnosis. Published by John Wiley & Sons, Ltd.

Mediation and moderation of psychological pain treatments: Response expectancies and hypnotic suggestibility.

The mediator role of response expectancies and the moderator role of hypnotic suggestibility were evaluated in the analogue treatment of pain. Approximately 1,000 participants were assessed for hypnotic suggestibility. Later, as part of a seemingly unrelated experiment, 188 of these individuals were randomly assigned to distraction, cognitive-behavioral package, hypnotic cognitive-behavioral package, hypnotic analgesia suggestion, placebo control, or no-treatment control conditions. Response expectancies partially mediated the effects of treatment on pain. Hypnotic suggestibility moderated treatment and was associated with the relief produced only by the hypnotic interventions. The results suggest that response expectancies are an important mechanism of hypnotic and cognitive-behavioral pain treatments and that hypnotic suggestibility is a trait variable that predicts hypnotic responding across situations, including hypnosis-based pain interventions.

The effects of hypnotic and nonhypnotic imaginative suggestion on pain

Few studies have compared placebo and suggested pain reduction. Hypnotic and nonhypnotic imaginative analgesia suggestions were compared against a placebo in reducing experimental pain. The mediator role of response expectancies and the moderator role of hypnotic and nonhypnotic imaginative suggestibility were evaluated. Sixty participants previously assessed for hypnotic and nonhypnotic imaginative suggestibility were assigned to one of two experimental conditions or a no-treatment control condition. In the "placebo first" condition, participants received placebo, followed by imaginative and then hypnotic analgesia suggestions. In the "placebo last" condition, participants received imaginative and then hypnotic suggestions, followed by placebo. Imaginative and hypnotic suggestions did not differ significantly and were more effective than no treatment in reducing pain. The placebo was no different from the analgesia suggestions and was more effective than no treatment, but only when administered after the suggestions. Pain reduction was mediated by expectancy but was not significantly related to suggestibility or hypnotizability, the latter operationalized as hypnotic suggestibility with imaginative suggestibility statistically controlled. In the general population, nonhypnotic imaginative suggestions may be as effective as hypnotic suggestions in reducing pain. Response expectancies would seem to be an important mechanism of placebo and suggested pain reduction.

Mediation and moderation of hypnotic and cognitive‐behavioural pain reduction

AbstractThe mediator function of response expectancies and the moderator function of hypnotic and non‐hypnotic imaginative suggestibility were evaluated in the analogue treatment of pain. One hundred and sixty‐seven participants previously assessed for hypnotic and imaginative suggestibility were randomly assigned to distraction, cognitive‐behavioural package (i.e., Stress Inoculation Training), hypnotic cognitive‐behavioural package, hypnotic analgesia suggestion, placebo control, or no‐treatment control conditions. The four ‘active’ treatments reduced pain more than the no‐treatment control condition. There was no statistical difference in effectiveness between these four treatments, but only the cognitive‐behavioural package reduced pain more than the placebo control condition. Response expectancies partially mediated the effects of treatment on pain. Imaginative suggestibility, defined as a generalized tendency to respond to imaginative suggestions delivered outside of hypnosis, moderated the effects of the cognitive‐behavioural package. Contrary to prediction, neither hypnotic suggestibility, nor hypnotizability (operationalized as hypnotic suggestibility with imaginative suggestibility statistically controlled) moderated the effects of the hypnotic treatments. Copyright © 2003 British Society of Experimental and Clinical Hypnosis

The role of compliance in hypnotic and nonhypnotic analgesia

We modified the standard procedure for administering finger pressure pain in order to assess the extent to which subjects biased their reports of pain reduction when exposed to compliance-inducing instructions. Experiment 1 used only highly hypnotizable subjects and found that compliance-induced reductions in reported pain were about half as large as the reported reductions produced by hypnotic analgesia suggestions. Experiment 2 used low as well as high hypnotizables and administered hypnotic or nonhypnotic analgesia instructions and compliance instructions to the same subjects on separate pain trials. Reported pain reductions produced by hypnotic and nonhypnotic analgesia suggestions and those produced by compliance instructions were substantially and significantly correlated. Furthermore, hypnotizability correlated with compliance-induced reported pain reductions as highly as it correlated with the reported reductions produced by hypnotic analgesia suggestions. Among high hypnotizables (but not low hypnotizables) compliant responding was predicted by social desirability. The findings of both studies indicate that compliance strongly influences the reports of hypnotic and nonhypnotic analgesia proffered by high hypnotizables. The role of compliance in the pain reductions reported by low hypnotizables is less clear-cut.

The effects of hypnotic suggestion on pain report.

Forty-five highly susceptible volunteers rated a series of shocks using 32 pain descriptors. Descriptors were given numerical values using magnitude estimation procedures. We assigned the subjects to one of three conditions, analgesia suggestion, relaxation suggestion, or no suggestion. All subjects were administered the shocks and the suggestion appropriate to the group, in both the waking and hypnotic state. The results support the existence of two dimensions of pain which are differentially responsive to suggestion. Hypnotic-analgesia suggestion altered subjects' perceptions of the intensity without changing their perceptions of the unpleasantness of the shocks. Hypnotic-relaxation suggestion reduced the unpleasantness but not the perceived intensity of the stimuli. These findings imply that research into hypnotic pain relief is more easily interpreted if pain is viewed as multidimensional in nature.