Hypnotism as a Function of Trance State Effects, Expectancy, and Suggestibility: An Italian Replication

Abstract

Previous research using stepwise regression analyses found self-reported hypnotic depth (srHD) to be a function of suggestibility, trance state effects, and expectancy. This study sought to replicate and expand that research using a general state measure of hypnotic responsivity, the Phenomenology of Consciousness Inventory: Hypnotic Assessment Procedure (PCI-HAP). Ninety-five participants completed an Italian translation of the PCI-HAP, with srHD scores predicted from the PCI-HAP assessment items. The regression analysis replicated the previous research results. Additionally, stepwise regression analyses were able to predict the srHD score equally well using only the PCI dimension scores. These results not only replicated prior research but suggest how this methodology to assess hypnotic responsivity, when combined with more traditional neurophysiological and cognitive-behavioral methodologies, may allow for a more comprehensive understanding of that enigma called hypnosis.

Abstract

Frühere Forschungen, die schrittweise Regressionsanalysen benutzten, fanden selbstbeschreibende hypnotische Tiefe (srHD) als eine Funktion der Suggestibilität, Trancezustandseffekten und Erwartung. Die vorliegende Studie versuchte, diese Forschung mittels einer generalisierten Zustandsmessung hypnotischen Ansprechvermögens, des Phenomenology of Consciousness Inventory, zu reproduzieren und zu erweitern: Hypnotic Assessment Procedure (PCI-HAP). 95 Teilnehmer füllten eine italienische Übersetzung des PCI-HAP mit durch PCI-HAP Merkmale vorhergesagten srHD-Punkten aus. Die Regressionsanalysen konnten den srHD Score auch nur mit den PCI Dimensionspunkten genauso gut vorhersagen. Diese Ergebnisse reproduzierten nicht nur frühere Forschungen, sondern legen auch nahe, wie diese Methode hypnotisches Ansprechvermögen erfassen und für ein umfassenderes Verständnis dieses Rätsels Hypnose sorgen könnte, wenn sie mit mehr traditionellen neurophysiologischen und kongitiv-behavioralen Methoden kombiniert würde.

Résumé

Une recherche antérieure effectuée à l’aide d’analyses de régression progressive avait permis de découvrir que la profondeur hypnotique (srHD) autodéclarée était fonction de la suggestibilité, des effets de l’état de transe et des attentes exprimées. La présente étude visait à répliquer et à étendre cette recherche à l’aide d’une mesure de l’état général de réceptivité hypnotique, soit l’Inventaire de la phénoménologie de la conscience: procédure d’évaluation hypnotique (PCI-PAH). On a administré à quatre-vingt-quinze participants une traduction italienne de l’échelle PCI-HAP, avec des scores srHD prédits par les items d’évaluation PCI-HAP. L’analyse de régression a reproduit les résultats de la recherche précédente. De plus, les analyses de régression progressive ont pu prédire le score srHD tout aussi bien en n’utilisant que les scores de dimension PCI. Non seulement ces résultats ont-ils reproduit ceux de la recherche antérieure, mais ils semblent indiquer que la façon dont cette méthodologie est utilisée pour évaluer la réceptivité hypnotique, lorsqu’elle est combinée avec des méthodologies neurophysiologiques et cognitivo-comportementales plus traditionnelles, peut permettre une meilleure compréhension de cette énigme qu’est l’hypnose.

Johanne Reynault

C. Tr. (STIBC)

Resumen

Investigaciones previas utilizando análisis de regresión paso a paso encontraron que la profundidad hipnótica autoreportada (PHar) era una función de sugestionabilidad, efectos de estados de trance, y expectación. Este estudio buscó replicar y expandir estas investigaciones usando una medición general del estado de respuesta a la hipnosis mediante el Inventario Fenomenológico de Conciencia: Procedimiento de Evaluación Hipnótica (PCI-HAP, por sus siglas en inglés). Noventa y cinco participantes completaron la traducción italiana del PCI-HAP, con las puntuaciones PHar predichas a partir de los reactivos del PCI-HAP. El análisis de regresión replicó los resultados de investigaciones previas. Adicionalmente, los análisis de regresión paso a paso pudieron predecir la puntuación PHar igualmente bien usando solo las puntuaciones de la dimensión PCI. Estos resultados no solo replicaron investigaciones anteriores, también sugieren cómo esta metodología para evaluar el nivel de respuesta hipnótica, cuando se combina con metodologías más tradicionales neurofisiológicas y cognitivo-conductuales, puede propiciar un entendimiento más comprensivo del enigma llamado hipnótico.

Omar Sánchez-Armáss Cappello

Autonomous University of San Luis Potosi, Mexico

Acknowledgments

The content of this presentation does not represent the views of the Department of Veterans Affairs nor the United States Government.

Funding

This research was supported by the financial contribution of the Italian Ministry of Health – Ricerca Corrente 2014–2015.

Notes

¹ Copies of the PCI (Pekala, 1982, 1991b), the PCI-HAP (Pekala, 1995a, 1995b), the therapist and self-report pre- and postassessment forms, the administration (Pekala, Kumar, & Maurer, 2009b), and interpretative (Pekala, 2009a) manuals, and the Microsoft Excel scoring program are available at www.quantifyingconsciousness.com. The Italian translation of the PCI and the PCI-HAP forms and induction protocol are also available from the aforementioned Web site (when completing the download, ask for the Italian version of the PCI/PCI-HAP).

² The PCI includes five items of similar or identical content that are used to generate a measure of how reliably participants completed the PCI. Scores above 2.0 are considered to be unreliable (scores from 2.0 to 2.20, marginally reliable).

³ For the data analysis, the scoring for the finger response item and the sleep state item were reversed to allow for more intuitive interpretation of the results.

⁴ Pre- and postassessment expectancy items, which were used to compute the total expectancy score, were not included in this analysis citation, since the total combined expectancy score subsumes their contribution.

⁵ It would be expected that the HRI score would correlate highly with the srHD score, since the HRI score is an average of the srHD score and the other three domain variables of the PCI-HAP (hypnoidal state, total combined expectancy, and imagoic suggestibility). The HRI also correlates highly with the other three domain scores (see Table 3). Its usefulness in predicting therapeutic efficacy must await future research.

⁶ Age data on the American sample is unavailable, that research having been completed over 20 years ago.

⁷ Standardized regression coefficients “can indicate, with a good deal of confidence, whether specific predictors make contributions to the criterion that are unrelated to the contributions made by the other variables in the analysis. Furthermore, interpreting the magnitudes of the coefficients can provide insight into the meaningfulness of those contributions” (Grimm & Yarnold, 1995, p. 41).

⁸ Whereas “phenomenological” refers to the general descriptive parameters associated with subjective/phenomenological experience, “noetic” refers to the more comprehensive quantification of that subjective/phenomenological experience via the PCI and/or similar types of quantitative retrospective, self-report inventories as defined in Pekala (2015, 2016).

⁹ The principle of stimulus-state specificity may help here. The principle of specificity states that, “across groups of randomly selected individuals, the same behaviors in the same stimulus setting (the same stimulus conditions), will be associated with the same intensities and patterns of phenomenological experience (the same phenomenological state), while different stimulus conditions will be associated with different intensities and/or patterns of phenomenological experience” (Pekala & Wenger, 1983, p. 255). To the extent that there are different instructional sets and stimulus cues associated with a given hypnotic induction/suggestion, such sets/cues would be presumed to activate different brain regions, leading to different neurophysiological, and corresponding noetic, effects.

Additional information

Funding

This research was supported by the financial contribution of the Italian Ministry of Health – Ricerca Corrente 2014–2015.