Brain Responses to Hypnotic Verbal Suggestions Predict Pain Modulation

Abstract

Background: The effectiveness of hypnosis in reducing pain is well supported by the scientific literature. Hypnosis typically involves verbal suggestions but the mechanisms by which verbal contents are transformed into predictive signals to modulate perceptual processes remain unclear. We hypothesized that brain activity during verbal suggestions would predict the modulation of responses to acute nociceptive stimuli.Methods: Brain activity was measured using BOLD-fMRI in healthy participants while they listened to verbal suggestions of HYPERALGESIA, HYPOALGESIA, or NORMAL sensation (control) following a standardized hypnosis induction. Immediately after the suggestions, series of noxious electrical stimuli were administered to assess pain-related responses. Brain responses measured during the suggestions were then used to predict changes in pain-related responses using delayed regression analyses.Results: Listening to suggestions of HYPERALGESIA and HYPOALGESIA produced BOLD decreases (vs. control) in the parietal operculum (PO) and in the anterior midcingulate cortex (aMCC), and increases in the left parahippocampal gyrus (lPHG). Changes in activity in PO, aMCC and PHG during the suggestions predicted larger pain-evoked responses following the HYPERALGESIA suggestions in the anterior cingulate cortex (ACC) and the anterior insula (aINS), and smaller pain-evoked responses following the HYPOALGESIA suggestions in the ACC, aMCC, posterior insula (pINS) and thalamus. These changes in pain-evoked brain responses are consistent with the changes in pain perception reported by the participants in HYPERALGESIA and HYPOALGESIA, respectively.Conclusions: The fronto-parietal network (supracallosal ACC and PO) has been associated with self-regulation and perceived self-agency. Deactivation of these regions during suggestions is predictive of the modulation of brain responses to noxious stimuli in areas previously associated with pain perception and pain modulation. The response of the hippocampal complex may reflect its role in contextual learning, memory and pain anticipation/expectations induced by verbal suggestions of pain modulation. This study provides a basis to further explore the transformation of verbal suggestions into perceptual modulatory processes fundamental to hypnosis neurophenomenology. These findings are discussed in relation to predictive coding models.

Resting state functional connectivity differentiation of neuropathic and nociceptive pain in individuals with chronic spinal cord injury

“… Chen et al, 2018 ). Pain-related alterations in rsFC between the parahippocampal gyrus and amygdala to cortical regions have also been previously identified, with the direction of association reported dependent on the cortical region and population (X. F. Chen et al, 2022 , Desmarteaux et al, 2021 , Mao et al, 2022 , Verriotis et al, 2022 ). In addition to their roles in pain processing, the parahippocampal gyrus and amygdala are involved in processes of emotion, memory, attention, and conditional learning through association of stimuli with positive or negative outcomes ( Aminoff et al, 2013 , Gallagher and Chiba, 1996 ).…”

Neuroscientific results of experimental studies on the control of acute pain with hypnosis and suggested analgesia

“…The objective of the study by Desmarteaux et al ( 2021 ) aimed to investigate how verbal hypnotic suggestions can affect perceptual processes during hypnosis. Brain activity was measured using BOLD-fMRI in a sample of 24 healthy individuals.…”

Analgesia for the Bayesian Brain: How Predictive Coding Offers Insights Into the Subjectivity of Pain

“…To name some examples, experienced meditators do not show pain reactions to thermal stimuli that cause significant pain in non-meditators [ 26 ]. Hypnotic suggestions reduce subjective pain in standardized pain stimuli along with causing alterations in fMRI patterns of the cingulate gyrus [ 27 ], parietal operculum, or the insula [ 28 ]. Listening to pleasant music will deflate the surprisal of a stimulus and though that its potential for pain and suffering [ 29 , 30 •].…”