Modulation of attentional bias by hypnosis: Disentangling the effect of induction and suggestion.

High resolution EEG indicators of pain responses in relation to hypnotic susceptibility and suggestion

Introduction Although sexual orgasm is typically a product of “bottom-up” genitosensory stimulation, it is also controlled by “top-down” processing of excitation and inhibition that controls both the timing of parasympathetic and sympathetic blood flow, and the subjective ability to “let go” into the orgasm when it is imminent. Consistent with this, orgasms activate cortical, limbic, hypothalamic, and brainstem structures, have characteristic pelvic floor muscle signatures and spinal cord activation that characterizes sexual “climax”, and can be rated subjectively in terms of the quality and type of sensory stimulation, affective experience, and the evaluation of pleasure. Orgasms are also accompanied by neurochemical and endocrine changes that characterize ecstatic pleasure, satiety, and refractoriness. Among these correlates is a consistent, orgasm-induced surge of prolactin released from the anterior pituitary into the peripheral bloodstream due to an immediate inhibition of dopamine. Orgasms can also be induced without genital stimulation. People experience orgasms during sleep, with exercise, with particular pelvic floor movements, and during hypnotic suggestion. Some women can have orgasms simply by engaging in imagery and fantasy. Paraplegic men and women also report “phantom” orgasms. This suggests that top-down control of orgasm can be activated on its own, suggesting a kind of “orgasm motor memory”. Objective To examine whether orgasms induced by hypnotic suggestion are “real,” in that they are accompanied by a prolactin surge, and how they are rated afterwards on Subjective, Affective, and Evaluative domains of the Orgasm Rating Scale (ORS; Mah and Binik, 2002). Hypnotic induction of laughter was used as a control condition. Methods Blood was taken before and immediately after each condition in 5 healthy premenopausal women who were susceptible to hypnotic induction and were fully clothed during the inductions. In addition to prolactin, blood plasma was assayed for LH, FSH, and total testosterone. Subjective ratings of the orgasms were made using the ORS, and compared to a separate group of age-matched women who used the ORS to rate orgasms induced by solo masturbation and partnered sex. Results Plasma prolactin increased to an average of 147% of baseline after hypnotic orgasm induction, but decreased to an average of 89% of baseline after hypnotic laughter induction. Changes in LH, FSH, and total T were not significant. Characteristic pelvic floor and abdominal contractions of orgasm were observed. Abdominal contractions were also observed with laughter. Relative to orgasms induced by solo masturbation and partnered sex, hypnotic orgasm induction showed the highest scores on the Subjective and Affective domains of the ORS, but did not differ in the Evaluative domain. Conclusions Hypnotic orgasm induction appears to be real, despite no direct genital stimulation. It is likely induced by top-down motor memory and pelvic floor stimulation of pudendal, hypogastric, and/or pelvic nerves. Hypnotic orgasm induction offers therapeutic intervention for women with orgasm difficulties. Disclosure Any of the authors act as a consultant, employee or shareholder of an industry for: FirmTech Inc. (USA); Kadence Bio (UK); Ovoca Bio/IVIX Corp. (Ireland); Reunion Neuroscience (Canada); SmartBod/Lioness, Inc. (USA); Vella Bioscience (USA).

Hypnosis is considered a unique tool capable of modulating cognitive processes. The extent to which hypnotic suggestions intervenes is still under debate. This study was designed to provide a new insight into this issue, by focusing on an unintentional emotional process: attentional bias. In Experiment 1, highly suggestible participants performed three sessions of an emotional Stroop task where hypnotic suggestions aiming to increase and decrease emotional reactivity towards emotional stimuli were administered within an intra-individual design. Compared to a baseline condition (without hypnotic suggestion), a significant increase in attentional bias was found when a hypnotic suggestion to increase emotional reactivity was administered. In contrast, the bias was eliminated when a suggestion to decrease emotional reactivity was administered. Experiment 2 investigated the effect of session repetition on attentional bias across three successive experimental sessions without hypnosis, and showed that the emotional Stroop effect did not vary across sessions. Hence, session repetition could not account for part of the modulation of attentional bias in Experiment 1. Taken together, the results suggest that specific hypnotic suggestions can influence elicitation of unintentional emotional processing. The implications are discussed regarding the locus of intervention of hypnotic suggestion in cognitive and emotional processes.

Structural and functional correlates of hypnotic depth and suggestibility

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.

Pain catastrophizing is associated with greater levels of pain. While many studies support the efficacy of hypnosis for pain, the effect on pain catastrophizing remains unclear. The present study evaluated the effect of hypnosis on pain catastrophizing using experimental heat stimulation. Twenty-two pain patients engaged in 3 conditions: baseline (no suggestion), hypnotic induction, and hypnotic induction plus analgesia suggestion. Participants with higher baseline pain showed a significant reduction in rumination following hypnotic induction plus analgesia suggestion and significant reductions in pain due to both the hypnotic induction alone and the hypnotic induction plus analgesia suggestion. The findings suggest that unpleasantness-focused hypnotic analgesia reduces pain via its effect on the rumination component of pain catastrophizing.

Impulsivity, self-control, and hypnotic suggestibility

Cigarette craving is a key contributor of nicotine addiction. Hypnotic aversion suggestions have been used to help smoking cessation and reduce smoking relapse rates but its neural basis is poorly understood. This study investigated the underlying neural basis of hypnosis treatment for nicotine addiction with resting state Electroencephalograph (EEG) coherence as the measure. The sample consisted of 42 male smokers. Cigarette craving was measured by the Tobacco Craving Questionnaire. The 8-minute resting state EEG was recorded in baseline state and after hypnotic induction in the hypnotic state. Then a smoking disgust suggestion was performed. A significant increase in EEG coherence in delta and theta frequency, and significant decrease in alpha and beta frequency, between the baseline and the hypnotic state was found, which may reflect alterations in consciousness after hypnotic induction. More importantly, the delta coherence between the right frontal region and the left posterior region predicted cigarette craving reduction after hypnotic aversion suggestions. This suggests that the functional connectivity between these regions plays an important role in reducing cigarette cravings via hypnotic aversion suggestions. Thus, these brain regions may serve as an important target to treat nicotine addiction, such as stimulating these brain regions via repetitive transcranial magnetic stimulation.

Fibromyalgia pain and its modulation by hypnotic and non-hypnotic suggestion: An fMRI analysis

The Absorption Scale, a measure of imaginative involvement, was administered to 64 subjects in the context of a hypnosis experiment and to an additional 64 subjects in a context unrelated to hypnosis. Expectancies of responding to hypnotic suggestions were assessed both before trance induction and after trance induction but before administration of hypnotic test suggestions. Hypnotic depth was assessed on the Long Stanford Scale (LSS) before the administration of test suggestions, and on the Inventory of Hypnotic Depth (IHD) after the hypnosis session. Absorption was correlated with hypnotic responsivity and expectancy, but only when assesed in the hypnotic context. Completing the Absorption Scale in a hypnotic context appeared to affect hypnotic responsiveness by altering subjects' expectancies. Only postinduction expectancies were uniquely predictive of response to hypnotic test suggestions, and all variables except the LSS were predictive of IHD scores. Results of path analysis supported the hypothesis that trance inductions alter expectancies for responding to hypnotic suggestions and that these altered expectancies determine subsequent hypnotic behavior.

Furnishing hypnotic instructions with implementation intentions enhances hypnotic responsiveness

Hypnosis, hypnotic suggestibility, memory, and involvement in films.

Differential patterns of spontaneous experiential response to a hypnotic induction: A latent profile analysis

Varieties of attention in hypnosis and meditation

Hypnosis can be conceived as a unique opportunity to explore how top-down effects can influence various conscious and non-conscious processes. In the field of perception, such modulatory effects have been described in distinct sensory modalities. In the present study we focused on the auditory channel and aimed at creating a radical deafness to elementary sounds by a specific hypnotic suggestion. We report here a single case-study in a highly suggestible healthy volunteer who reported a total hypnotically suggested deafness. We recorded high-density scalp EEG during an auditory odd-ball paradigm before and after hypnotic deafness suggestion. While both early auditory event-related potentials to sounds (P1) and mismatch negativity component were not affected by hypnotic deafness, we observed a total disappearance of the late P3 complex component when the subject reported being deaf. Moreover, a centro-mesial positivity was present exclusively during the hypnotic condition prior to the P3 complex. Interestingly, source localization suggested an anterior cingulate cortex (ACC) origin of this neural event. Multivariate decoding analyses confirmed and specified these findings. Resting state analyses confirmed a similar level of conscious state in both conditions, and suggested a functional disconnection between auditory areas and other cortical areas. Taken together these results suggest the following plausible scenario: (i) preserved early processing of auditory information unaffected by hypnotic suggestion, (ii) conscious setting of an inhibitory process (ACC) preventing conscious access to sounds, (iii) functional disconnection between the modular and unconscious representations of sounds and global neuronal workspace. This single subject study presents several limits that are discussed and remains open to alternative interpretations. This original proof-of-concept paves the way to a larger study that will test the predictions stemming from our theoretical model and from this first report.