The role of frontal executive functions in hypnosis and hypnotic suggestibility.

Abstract

There is both theoretical and empirical evidence supporting a role for frontal executive functions (FEFs) in hypnosis and hypnotic suggestibility. However, the precise nature of this involvement is debated. While there is clear evidence that FEFs are impaired under hypnosis, the cause of this decreased function is unclear. Theories make differing predictions as to the role of FEFs in hypnotic suggestibility, with some arguing that decreased baseline (normal function outside of the hypnotic context) FEFs lead to greater hypnotic suggestibility and others arguing that increased baseline FEFs lead to greater hypnotic suggestibility. Other theories posit that suggestibility is more a consequence of attitude rather than aptitude. The present work provides a critical review of the involvement of FEFs in hypnosis and hypnotic suggestibility. The review considers behavioral evidence from studies employing putative frontal lobe tasks including tests of fluid intelligence and both task- and nontask-based neuroimaging evidence. It is determined that the evidence to date is inconclusive and that more work is needed to establish a necessary and sufficient role for FEFs in hypnosis or hypnotic suggestibility. Recommendations are made for future research.

Strategies that reduce Stroop interference

“…As argued earlier, the cold control theory assumes that hypnotisability is only related to metacognitive abilities and so strategies used during hypnosis should be applicable to anyone inside and outside of hypnosis. Empirical evidence is in harmony with this assumption (Dienes, et al, 2009;Parris, 2017;Varga, Németh, & Szekely, 2011). Hence, we can test cold control theory by requesting participants from the whole range of hypnotisability to use a specific strategy during the Stroop task.…”

“…Hence, identifying successful strategies is crucial to understand how highs can manage to reduce the interference effect when they respond to the word blindness suggestion, and by this we can unravel the mystery surrounding the suggestion. Importantly, the ability of highs to respond hypnotically (with the feeling of involuntariness) seems to be independent of their first-order executive functions, such as cognitive inhibition (Dienes et al, 2009) and selective attention (Varga, Németh, & Szekely, 2011), that could help them overcome cognitive conflict during the Stroop task (see Parris, 2017, for a review). We found no evidence one way or the other for a correlation between hypnotisability and the extent to which any of the strategies could decrease Stroop interference.…”

Metacognition of agency is reduced in high hypnotic suggestibility

“…Patients with schizophrenia also significantly overestimated their performance compared with controls, whereas highly suggestible individuals did not; these results suggest that patients exhibit a broad deficit in metacognition whereas aberrant metacognition in highly suggestible individuals may be specific to the sense of agency. Further independent evidence for differences between these groups comes from data showing that patients with schizophrenia display attenuated or normal hypnotic suggestibility (Frischholz, Lipman, Braun, & Sachs, 1992) and that the majority of highly suggestible individuals have a healthy cognitive profile (Parris, 2017;Terhune & Cardeña, 2015). Nevertheless, the shared response patterns of these two groups indicate that highly suggestible individuals may provide a valuable model for distortions in the sense of agency (Polito et al, 2015;Terhune et al, in press;Walsh et al, 2015) and are consistent with preliminary research linking hypnotic suggestibility to schizotypy (Connors et al, 2014;Gruzelier et al, 2004), which is similarly characterized by aberrant sense of agency (Moore & Bravin, 2015).…”

Effect of hypnotic suggestion on cognition and craving in smokers

“…Last, it is possible that in the hypnotic suggestion condition participants may have experienced reduced frontal lobe function so that top-down control would be compromised, preventing the reduction of Stroop interference (see Parris, 2017). Further reseach can experimentally manipulate procedural features of the hypnotic suggestion to examine the effect of these methodological factors on study outcomes.…”