Hypnotizability, Hypnosis and Prepulse Inhibition of the Startle Reflex in Healthy Women: An ERP Analysis

Abstract

A working model of the neurophysiology of hypnosis suggests that highly hypnotizable individuals (HHs) have more effective frontal attentional systems implementing control, monitoring performance, and inhibiting unwanted stimuli from conscious awareness, than low hypnotizable individuals (LHs). Recent studies, using prepulse inhibition (PPI) of the auditory startle reflex (ASR), suggest that HHs, in the waking condition, may show reduced sensory gating although they may selectively attend and disattend different stimuli. Using a within subject design and a strict subject selection procedure, in waking and hypnosis conditions we tested whether HHs compared to LHs showed a significantly lower inhibition of the ASR and startle-related brain activity in both time and intracerebral source localization domains. HHs, as compared to LH participants, exhibited (a) longer latency of the eyeblink startle reflex, (b) reduced N100 responses to startle stimuli, and (c) higher PPI of eyeblink startle and of the P200 and P300 waves. Hypnosis yielded smaller N100 waves to startle stimuli and greater PPI of this component than in the waking condition. sLORETA analysis revealed that, for the N100 (107 msec) elicited during startle trials, HHs had a smaller activation in the left parietal lobe (BA2/40) than LHs. Auditory pulses of pulse-with prepulse trials in HHs yielded less activity of the P300 (280 msec) wave than LHs, in the cingulate and posterior cingulate gyrus (BA23/31). The present results, on the whole, are in the opposite direction to PPI findings on hypnotizability previously reported in the literature. These results provide support to the neuropsychophysiological model that HHs have more effective sensory integration and gating (or filtering) of irrelevant stimuli than LHs.

Pain Modulation in Waking and Hypnosis in Women: Event-Related Potentials and Sources of Cortical Activity

“…In addition, since the P2 wave is believed to reflect the painfulness of the stimuli [ 74 , 94 ], we think that both P200 and N140 amplitude changes associated to hypoalgesia or hyperalgesia effects during hypnosis, may reflect, respectively, the operation of a top-down inhibition or sensitization process of pain sensation [ 49 , 57 , 101 , 102 ]. This conclusion seems in agreement with Horton and colleagues neuroimaging findings of a larger rostrum in HHs, compared to LHs, indicating a more efficient mechanism of sensory gating in the former than the latter [ 53 , 103 ].…”

Cerebellar Structural Variations in Subjects with Different Hypnotizability

“…Related to the present topic, the temporal and parietal cortices have been even implicated in individual differences of hypnotic susceptibility or in different facets of hypnotic responding [13,14]. Further, during hypnotic hyperalgesia altered activity within supramarginal and superior, middle, inferior temporal gyri was described [53].…”

New directions in hypnosis research: strategies for advancing the cognitive and clinical neuroscience of hypnosis

“…This research should endeavor to isolate and further clarify heterogeneity in hypnotic responding, including the potential roles of different cognitive functions in distinct subgroups of lows, mediums (see the section, later in this article, on the importance of studying mediums), and highs ( Barber 1999 ; Terhune et al 2011 ). Such research should focus on a number of underlying systems and processes, including the effects of hypnotic suggestions on activity in specific areas of the brain ( De Pascalis and Russo 2013 ), changing patterns of functional connectivity between brain areas or within and between networks ( Cojan et al 2009 ; Jiang et al 2016 ), and the functional role of different frequencies of brain oscillations ( De Pascalis et al 2004 ; De Pascalis 2007 ; Jensen et al 2015 ).…”