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Niedernhuber M, Schroeder AC, Lercher C, Bruegger M, Prates de Matos NM, Noreika V, Lenggenhager B. An interhemispheric frontoparietal network supports hypnotic states. Cortex 2024; 177:180-193. [PMID: 38865762 DOI: 10.1016/j.cortex.2024.05.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 02/22/2024] [Accepted: 05/13/2024] [Indexed: 06/14/2024]
Abstract
Understanding the neural substrate of altered conscious states is an important cultural, scientific, and clinical endeavour. Although hypnosis causes strong shifts in conscious perception and cognition, it remains largely unclear how hypnosis affects information processing in cortical networks. Here we manipulated the depth of hypnotic states to study information processing between cortical regions involved in attention and awareness. We used high-density Electroencephalography (EEG) to record resting-state cortical activity from 30 hypnosis experts during two hypnotic states with different depth. Each participant entered a light and a deep hypnotic state as well as two well-matched control states. Bridging top-down and lateralisation models of hypnosis, we found that interhemispheric frontoparietal connectivity distinguished hypnosis and control conditions, while no difference was found between the two hypnotic states. Using a graph-theoretic measure, we revealed that the amount of information passing through individual nodes (measured via betweenness centrality) is reduced during hypnosis relative to control states. Finally, we found that theta power was enhanced during hypnosis. Our result contributes to the current discussion around a role for theta power in bringing about hypnotic states, as well as other altered conscious states. Overall, our findings support the notion that altered top-down control in frontoparietal regions facilitates hypnosis by integrating information between cortical hemispheres.
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Affiliation(s)
- Maria Niedernhuber
- Department of Psychology, University of Cambridge, Downing Pl, Cambridge, United Kingdom; Department of Psychology, University of Zurich, Binzmuehlestrasse 14, Zurich, Switzerland.
| | | | - Céline Lercher
- Department of Psychology, University of Zurich, Binzmuehlestrasse 14, Zurich, Switzerland
| | - Mike Bruegger
- Center of Dental Medicine, University of Zurich, Plattenstrasse 11, Zurich, Switzerland
| | | | - Valdas Noreika
- Department of Psychology, School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London, United Kingdom
| | - Bigna Lenggenhager
- Department of Psychology, University of Zurich, Binzmuehlestrasse 14, Zurich, Switzerland; Department of Psychology, University of Konstanzs, Universitätsstraße 10, Konstanz, Germany
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Toriz H, Fagetti A, Terán-Pérez G, Mercadillo RE. Neuroanthropology of shamanic trance: a case study with a ritual specialist from Mexico. Front Psychol 2024; 15:1325188. [PMID: 38505362 PMCID: PMC10948424 DOI: 10.3389/fpsyg.2024.1325188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Accepted: 02/15/2024] [Indexed: 03/21/2024] Open
Abstract
In Mexico, shamans are recognized for the gift of entering a deep trance that allows them to know the origin of the diseases and conflicts that afflict people. They commonly treat patients through limpias (cleansing) to extract negative elements sent by a witch or that were "collected" in places that harbor "evil winds." We present a case study of an 81-year-old Mexican shaman who noticed her gift in childhood. Electroencephalographic recordings were made while the shaman performed three activities: reading cards to diagnose a patient and answer the questions he posed; limpia with chicken eggs, stones, and bells to absorb adverse "things"; and the incorporation trance through which the deceased is believed to occupy the shaman's body to use it as a communication channel. Alpha activity was observed when concentrated, suggesting a hypnagogic-like state. Predominant beta and gamma oscillations were observed, suggesting a potential plastic phenomenon that modulates the assimilation of external and internal referents guiding temporal schemes for action, attention, and the integration of mnemonic, sensory, and imaginative elements. We used a neuroanthropological approach to understand shamanic trance as a biological potential of the human brain to induce non-ordinary states of consciousness linked to cultural beliefs and practices.
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Affiliation(s)
- Hugo Toriz
- National School of Anthropology and History, Mexico City, Mexico
| | - Antonella Fagetti
- Instituto de Ciencias Sociales y Humanidades, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | | | - Roberto E. Mercadillo
- Neurosciences Area, Biology of Reproduction Department, Universidad Autónoma Metropolitana, Mexico City, Mexico
- CONAHCYT, Mexico City, Mexico
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Obukhov NV, Naish PLN, Solnyshkina IE, Siourdaki TG, Martynov IA. Real-time assessment of hypnotic depth, using an EEG-based brain-computer interface: a preliminary study. BMC Res Notes 2023; 16:288. [PMID: 37875937 PMCID: PMC10599062 DOI: 10.1186/s13104-023-06553-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 10/02/2023] [Indexed: 10/26/2023] Open
Abstract
OBJECTIVE Hypnosis can be an effective treatment for many conditions, and there have been attempts to develop instrumental approaches to continuously monitor hypnotic state level ("depth"). However, there is no method that addresses the individual variability of electrophysiological hypnotic correlates. We explore the possibility of using an EEG-based passive brain-computer interface (pBCI) for real-time, individualised estimation of the hypnosis deepening process. RESULTS The wakefulness and deep hypnosis intervals were manually defined and labelled in 27 electroencephalographic (EEG) recordings obtained from eight outpatients after hypnosis sessions. Spectral analysis showed that EEG correlates of deep hypnosis were relatively stable in each patient throughout the treatment but varied between patients. Data from each first session was used to train classification models to continuously assess deep hypnosis probability in subsequent sessions. Models trained using four frequency bands (1.5-45, 1.5-8, 1.5-14, and 4-15 Hz) showed accuracy mostly exceeding 85% in a 10-fold cross-validation. Real-time classification accuracy was also acceptable, so at least one of the four bands yielded results exceeding 74% in any session. The best results averaged across all sessions were obtained using 1.5-14 and 4-15 Hz, with an accuracy of 82%. The revealed issues are also discussed.
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Affiliation(s)
- Nikita V Obukhov
- Research Department, The Association of Experts in the Field of Clinical Hypnosis, 40, Kamennoostrovsky Ave., 410, Saint Petersburg, 197022, Russian Federation.
- Department of Psychotherapy, Academician I.P. Pavlov First St. Petersburg State Medical University, 6-8, L. Tolstoy str, Saint Petersburg, 197022, Russian Federation.
| | - Peter L N Naish
- Department of Psychology, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK
| | - Irina E Solnyshkina
- Department of Psychotherapy, Academician I.P. Pavlov First St. Petersburg State Medical University, 6-8, L. Tolstoy str, Saint Petersburg, 197022, Russian Federation
| | - Tatiana G Siourdaki
- Research Department, The Association of Experts in the Field of Clinical Hypnosis, 40, Kamennoostrovsky Ave., 410, Saint Petersburg, 197022, Russian Federation
| | - Ilya A Martynov
- Research Department, The Association of Experts in the Field of Clinical Hypnosis, 40, Kamennoostrovsky Ave., 410, Saint Petersburg, 197022, Russian Federation
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Callara AL, Zelič Ž, Fontanelli L, Greco A, Santarcangelo EL, Sebastiani L. Is Hypnotic Induction Necessary to Experience Hypnosis and Responsible for Changes in Brain Activity? Brain Sci 2023; 13:875. [PMID: 37371355 DOI: 10.3390/brainsci13060875] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 05/23/2023] [Accepted: 05/27/2023] [Indexed: 06/29/2023] Open
Abstract
The relevance of formal hypnotic induction to the experience of trance and its neural correlates is not clear, in that hypnotizability, beliefs and expectation of hypnosis may play a major role. The aim of the study was assessing the EEG brain activity of participants with high (highs) or low hypnotizability scores (lows), aware of their hypnotizability level and informed that the session will include simple relaxation, formal hypnotic induction and neutral hypnosis. A total of 16 highs and 15 lows (according to the Stanford Hypnotic Susceptibility Scale, form A) were enrolled. Their EEGs were recorded during consecutive conditions of open/closed-eyes relaxation, hypnotic induction, neutral hypnosis and post hypnosis not interrupted by interviews. The studied variables were theta, alpha and gamma power spectral density (PSD), and the Determinism (DET) and Entropy (ENT) of the EEG signal Multidimensional Recurrence Plot (mRP). Highs reported significantly greater changes in their state of consciousness than lows across the session. The theta, alpha and gamma PSD did not exhibit condition-related changes in both groups. The Alpha PSD was larger in highs than in lows on midline sites, and the different sides/regions' theta and gamma PSD were observed in the two groups independently from conditions. ENT showed no correlation with hypnotizability, while DET positively correlated with hypnotizability during hypnosis. In conclusion, the relevance of formal hypnotic induction to the experience of trance may be scarce in highs, as they are aware of their hypnotizability scores and expecting hypnosis. Cognitive processing varies throughout the session depending on the hypnotizability level.
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Affiliation(s)
| | - Žan Zelič
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy
| | - Lorenzo Fontanelli
- Department of Clinical and Experimental Medicine, University of Pisa, 56127 Pisa, Italy
| | - Alberto Greco
- Department of Information Engineering, University of Pisa, 56126 Pisa, Italy
| | - Enrica Laura Santarcangelo
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy
| | - Laura Sebastiani
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy
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Császár N, Scholkmann F, Bókkon I. Implications on hypnotherapy: Neuroplasticity, epigenetics and pain. Neurosci Biobehav Rev 2021; 131:755-764. [PMID: 34619172 DOI: 10.1016/j.neubiorev.2021.10.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 09/07/2021] [Accepted: 10/01/2021] [Indexed: 01/11/2023]
Abstract
We provide a brief review about the significance of hypnosis with respect to applications and physiological processes in hypnotherapy. Our review concludes that hypnosis is a promising method to manage acute and chronic pain. In addition, we discuss indications pointing toward the view that hypnosis can induce changes in neuroplasticity possibly involving epigenetic mechanisms.
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Affiliation(s)
- N Császár
- National University of Public Services, Budapest, Hungary; Psychosomatic Outpatient Clinics, Budapest, Hungary.
| | - F Scholkmann
- Biomedical Optics Research Laboratory, Department of Neonatology, University Hospital Zurich, University of Zurich, Switzerland.
| | - I Bókkon
- Psychosomatic Outpatient Clinics, Budapest, Hungary; Vision Research Institute, Neuroscience and Consciousness Research Department, Lowell, MA, USA.
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