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Northoff G, Zilio F, Zhang J. Beyond task response-Pre-stimulus activity modulates contents of consciousness. Phys Life Rev 2024; 49:19-37. [PMID: 38492473 DOI: 10.1016/j.plrev.2024.03.002] [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: 02/28/2024] [Accepted: 03/03/2024] [Indexed: 03/18/2024]
Abstract
The current discussion on the neural correlates of the contents of consciousness (NCCc) focuses mainly on the post-stimulus period of task-related activity. This neglects the substantial impact of the spontaneous or ongoing activity of the brain as manifest in pre-stimulus activity. Does the interaction of pre- and post-stimulus activity shape the contents of consciousness? Addressing this gap in our knowledge, we review and converge two recent lines of findings, that is, pre-stimulus alpha power and pre- and post-stimulus alpha trial-to-trial variability (TTV). The data show that pre-stimulus alpha power modulates post-stimulus activity including specifically the subjective features of conscious contents like confidence and vividness. At the same time, alpha pre-stimulus variability shapes post-stimulus TTV reduction including the associated contents of consciousness. We propose that non-additive rather than merely additive interaction of the internal pre-stimulus activity with the external stimulus in the alpha band is key for contents to become conscious. This is mediated by mechanisms on different levels including neurophysiological, neurocomputational, neurodynamic, neuropsychological and neurophenomenal levels. Overall, considering the interplay of pre-stimulus intrinsic and post-stimulus extrinsic activity across wider timescales, not just evoked responses in the post-stimulus period, is critical for identifying neural correlates of consciousness. This is well in line with both processing and especially the Temporo-spatial theory of consciousness (TTC).
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Affiliation(s)
- Georg Northoff
- University of Ottawa, Institute of Mental Health Research at the Royal Ottawa Hospital, Ottawa, Canada.
| | - Federico Zilio
- Department of Philosophy, Sociology, Education and Applied Psychology, University of Padua, Padua, Italy
| | - Jianfeng Zhang
- Center for Brain Disorders and Cognitive Sciences, School of Psychology, Shenzhen University, Shenzhen, China.
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2
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Gonçalves ÓF, Sayal J, Lisboa F, Palhares P. The experimental study of consciousness: Is psychology travelling back to the future? Int J Clin Health Psychol 2024; 24:100475. [PMID: 39021679 PMCID: PMC11253270 DOI: 10.1016/j.ijchp.2024.100475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 05/29/2024] [Indexed: 07/20/2024] Open
Abstract
It was with the promise of rendering an experimental approach to consciousness that psychology started its trajectory as an independent science more than 150 years ago. Here, we will posit that the neurosciences were instrumental in leading psychology to resume the study of consciousness by projecting an empirical agenda for the future. First, we will start by showing how scientists were able to venture into the consciousness of supposedly unconscious patients, opening the door for the identification of important neural correlates of distinct consciousness states. Then, we will describe how different technological advances and elegant experimental paradigms helped in establishing important neuronal correlates of global consciousness (i.e., being conscious at all), perceptual consciousness (i.e., being conscious of something), and self-consciousness (i.e., being conscious of itself). Finally, we will illustrate how the study of complex consciousness experiences may contribute to the clarification of the mechanisms associated with global consciousness, the relationship between perceptual and self-consciousness, and the interface among distinct self-consciousness domains. In closing, we will elaborate on the road ahead of us for re-establishing psychology as a science of consciousness.
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Affiliation(s)
| | - Joana Sayal
- Proaction Lab – CINEICC, Faculty of Psychology and Educational Sciences, University of Coimbra, Colégio de Jesus, R. Inácio Duarte 65, Coimbra 3000-481, Portugal
| | - Fábio Lisboa
- Proaction Lab – CINEICC, Faculty of Psychology and Educational Sciences, University of Coimbra, Colégio de Jesus, R. Inácio Duarte 65, Coimbra 3000-481, Portugal
| | - Pedro Palhares
- Proaction Lab – CINEICC, Faculty of Psychology and Educational Sciences, University of Coimbra, Colégio de Jesus, R. Inácio Duarte 65, Coimbra 3000-481, Portugal
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3
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Martial C, Fritz P, Cassol H, Gosseries O, Lambermont B, Misset B, Rousseau AF. Phenomenological memory characteristics and impact of near-death experience in critically ill survivors: Observations at discharge and after a 1-year follow-up. Int J Clin Health Psychol 2024; 24:100478. [PMID: 38988974 PMCID: PMC11231695 DOI: 10.1016/j.ijchp.2024.100478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Accepted: 06/10/2024] [Indexed: 07/12/2024] Open
Abstract
Background It is not rare that intensive care unit (ICU) patients report unusual subjective experiences, ranging from a feeling of harmony with the environment to complex phenomena such as near-death experience (NDE). This 1-year follow-up study investigates the characteristics and potential global impact of the NDE memories recalled by ICU survivors. Method We prospectively enrolled 126 adult survivors of a prolonged (>7days) ICU stay (all etiologies), including 19 (15 %) who reported a NDE as identified by the Greyson NDE scale. The NDE group underwent a semi-structured interview one month later evaluating their memory characteristics and the associated life-threatening situation. One year after inclusion, all patients (regardless of whether they recalled an NDE) were contacted for a follow-up Greyson NDE scale assessment and questions about their ICU experience and opinions on death since discharge. Results The Greyson NDE scale revealed that the most frequently reported features were altered time perception, heightened senses and life review, and the Greyson total scores did not evolve over time. NDE memories persisted, with a consequent number of phenomenological characteristics (e.g., visual details, emotions). One year post-ICU, two patients (18 %) of the NDE group and 12 (24 %) of the non-NDE group were less afraid of death. Conclusions Results emphasize the clinical importance of interviewing all ICU patients to explore any memory after an ICU stay.
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Affiliation(s)
- Charlotte Martial
- Coma Science Group, GIGA-Consciousness, University of Liège, Avenue de l'hôpital, 11, Liège 4000, Belgium
- Centre du Cerveau, University Hospital of Liège, Avenue de l'hôpital, 11, Liège 4000, Belgium
| | - Pauline Fritz
- Coma Science Group, GIGA-Consciousness, University of Liège, Avenue de l'hôpital, 11, Liège 4000, Belgium
- Centre du Cerveau, University Hospital of Liège, Avenue de l'hôpital, 11, Liège 4000, Belgium
| | - Helena Cassol
- Coma Science Group, GIGA-Consciousness, University of Liège, Avenue de l'hôpital, 11, Liège 4000, Belgium
- Physical and Rehabilitation Medicine Department, University Hospital of Liège, University of Liège, Avenue de l'Hôpital, 1, Liège 4000, Belgium
| | - Olivia Gosseries
- Coma Science Group, GIGA-Consciousness, University of Liège, Avenue de l'hôpital, 11, Liège 4000, Belgium
- Centre du Cerveau, University Hospital of Liège, Avenue de l'hôpital, 11, Liège 4000, Belgium
| | - Bernard Lambermont
- Department of Intensive Care, University Hospital of Liège and University of Liège, Avenue de l'hôpital, 1, Liège 4000, Belgium
| | - Benoit Misset
- Department of Intensive Care, University Hospital of Liège and University of Liège, Avenue de l'hôpital, 1, Liège 4000, Belgium
| | - Anne-Françoise Rousseau
- Department of Intensive Care, University Hospital of Liège and University of Liège, Avenue de l'hôpital, 1, Liège 4000, Belgium
- Research Unit for a Life-Course Perspective on Health & Education (RUCHE), University of Liège, Avenue de l'hôpital, 1, Liège 4000, Belgium
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4
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Hansen E. Touching the unconscious in the unconscious - hypnotic communication with unconscious patients. Front Psychol 2024; 15:1389449. [PMID: 38966734 PMCID: PMC11223660 DOI: 10.3389/fpsyg.2024.1389449] [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: 02/21/2024] [Accepted: 05/30/2024] [Indexed: 07/06/2024] Open
Abstract
If hypnosis means contact to the unconscious to modulate psychological and physiological functions by means of suggestions, and if this is facilitated by attenuation of the critical mind, then the question arises as to whether suggestions also have an effect when waking consciousness is otherwise eliminated, namely by coma or anesthesia. A prerequisite would be perception, which actually is evidenced by reports of patients after traumatic brain injury, artificial coma, resuscitation or general anesthesia. Moreover, posttraumatic stress disorder (PTSD) frequently observed after these medical situations is hardly explainable without some sort of awareness under such conditions. Even advanced neurophysiological diagnostic cannot yet rule out consciousness or sensory processing. Especially reference to perception during unconsciousness is given by the results of a recent multicenter study on the effects of hypnotic communication with patients under controlled adequate deep general anesthesia. The observed reductions in incidence and severity of postoperative pain, opioid use, nausea and vomiting cannot be explained by the reaction of a few but only by a considerable proportion of patients. This leads to a strong plea for a more careful treatment of unconscious patients in the emergency room, operating theater or intensive care unit, for the abandonment of the restriction of therapeutic communication to awake patients, and for new aspects of communication and hypnosis research. Obviously, loss of consciousness does not protect against psychological injury, and continuation of communication is needed. But how and what to talk to unconscious patients? Generally addressing the unconscious mind with suggestions that generally exert their effects unconsciously, hypnotic communication appears to be the adequate language. Especially addressing meaningful topics, as derived from the basic psychological needs and known stressors, appears essential. With respect to negative effects by negative or missing communication or to the proposed protective and supporting effects of therapeutic communication with patients clinically rated as unconscious, the role of consciousness is secondary. For the effects of perceived signals and suggestions it does not matter whether consciousness is absent, or partial, or unrecognized present.
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Affiliation(s)
- Ernil Hansen
- Department of Anesthesiology, University Hospital Regensburg, Regensburg, Germany
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5
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Cardone P, Alnagger N, Annen J, Bicego A, Gosseries O, Martial C. Psychedelics and disorders of consciousness: the current landscape and the path forward. Neurosci Conscious 2024; 2024:niae025. [PMID: 38881630 PMCID: PMC11179162 DOI: 10.1093/nc/niae025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 02/16/2024] [Accepted: 05/20/2024] [Indexed: 06/18/2024] Open
Abstract
Modern medicine has been shaken by the surge of psychedelic science that proposes a new approach to mitigate mental disorders, such as depression and post-traumatic stress disorder. Clinical trials to investigate whether psychedelic substances can treat psychiatric conditions are now underway, yet less discussion gravitates around their use in neurological disorders due to brain injury. One suggested implementation of brain-complexity enhancing psychedelics is to treat people with post-comatose disorders of consciousness (DoC). In this article, we discuss the rationale of this endeavour, examining possible outcomes of such experiments by postulating the existence of an optimal level of complexity. We consider the possible counterintuitive effects of both psychedelics and DoC on the functional connectivity of the default mode network and its possible impact on selfhood. We also elaborate on the role of computational modelling in providing complementary information to experimental studies, both contributing to our understanding of the treatment mechanisms and providing a path towards personalized medicine. Finally, we update the discourse surrounding the ethical considerations, encompassing clinical and scientific values.
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Affiliation(s)
- Paolo Cardone
- Coma Science Group, GIGA-Consciousness, University of Liège, Avenue de l'hôpital 11, Liège 4000, Belgium
- Centre du Cerveau2, University Hospital of Liège, Avenue de l'hôpital 11, Liège 4000, Belgium
| | - Naji Alnagger
- Coma Science Group, GIGA-Consciousness, University of Liège, Avenue de l'hôpital 11, Liège 4000, Belgium
- Centre du Cerveau2, University Hospital of Liège, Avenue de l'hôpital 11, Liège 4000, Belgium
| | - Jitka Annen
- Coma Science Group, GIGA-Consciousness, University of Liège, Avenue de l'hôpital 11, Liège 4000, Belgium
- Centre du Cerveau2, University Hospital of Liège, Avenue de l'hôpital 11, Liège 4000, Belgium
- Department of Data Analysis, University of Ghent, Henri Dunantlaan 1, Ghent 9000, Belgium
| | - Aminata Bicego
- Sensation and Perception Research Group, GIGA-Consciousness, University of Liège, Avenue de l'hôpital 11, Liège 4000, Belgium
| | - Olivia Gosseries
- Coma Science Group, GIGA-Consciousness, University of Liège, Avenue de l'hôpital 11, Liège 4000, Belgium
- Centre du Cerveau2, University Hospital of Liège, Avenue de l'hôpital 11, Liège 4000, Belgium
- Sensation and Perception Research Group, GIGA-Consciousness, University of Liège, Avenue de l'hôpital 11, Liège 4000, Belgium
| | - Charlotte Martial
- Coma Science Group, GIGA-Consciousness, University of Liège, Avenue de l'hôpital 11, Liège 4000, Belgium
- Centre du Cerveau2, University Hospital of Liège, Avenue de l'hôpital 11, Liège 4000, Belgium
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6
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Mashour GA, Lee U, Pal D, Li D. Consciousness and the Dying Brain. Anesthesiology 2024; 140:1221-1231. [PMID: 38603803 PMCID: PMC11096058 DOI: 10.1097/aln.0000000000004970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 02/26/2024] [Indexed: 04/13/2024]
Abstract
The near-death experience has been reported since antiquity and is often characterized by the perception of light, interactions with other entities, and life recall. Near-death experiences can occur in a variety of situations, but they have been studied systematically after in-hospital cardiac arrest, with an incidence of 10 to 20%. Long attributed to metaphysical or supernatural causes, there have been recent advances in understanding the neurophysiologic basis of this unique category of conscious experience. This article reviews the epidemiology and neurobiology of near-death experiences, with a focus on clinical and laboratory evidence for a surge of neurophysiologic gamma oscillations and cortical connectivity after cardiac and respiratory arrest.
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Affiliation(s)
- George A. Mashour
- Department of Anesthesiology, Center for Consciousness Science, Neuroscience Graduate Program, Department of Pharmacology, University of Michigan Medical School, Ann Arbor, Michigan
| | - UnCheol Lee
- Department of Anesthesiology, Center for Consciousness Science, University of Michigan Medical School, Ann Arbor, Michigan
| | - Dinesh Pal
- Department of Anesthesiology, Center for Consciousness Science and Neuroscience Graduate Program, Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Duan Li
- Department of Anesthesiology, Center for Consciousness Science, University of Michigan Medical School, Ann Arbor, Michigan
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7
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Kovoor JG, Santhosh S, Stretton B, Tan S, Gouldooz H, Moorthy S, Pietris J, Hannemann C, Yu LK, Johnson R, Reddi BA, Gupta AK, Wagner M, Page GJ, Kovoor P, Bastiampillai T, Maddocks I, Perry SW, Wong ML, Licinio J, Bacchi S. Near-death experiences after cardiac arrest: a scoping review. DISCOVER MENTAL HEALTH 2024; 4:19. [PMID: 38806961 PMCID: PMC11133272 DOI: 10.1007/s44192-024-00072-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Accepted: 05/24/2024] [Indexed: 05/30/2024]
Abstract
BACKGROUND This scoping review aimed to characterise near-death experiences in the setting of cardiac arrest, a phenomenon that is poorly understood and may have clinical consequences. METHOD PubMed/MEDLINE was searched to 23 July 2023 for prospective studies describing near-death experiences in cardiac arrest. PRISMA-ScR guidelines were adhered to. Qualitative and quantitative data were synthesised. Meta-analysis was precluded due to data heterogeneity. RESULTS 60 records were identified, of which 11 studies involving interviews were included from various countries. Sample size ranged from 28-344, and proportion of female patients (when reported) was 0-50%, with mean age (when reported) ranging 54-64 years. Comorbidities and reasons for cardiac arrest were heterogeneously reported. Incidence of near-death experiences in the included studies varied from 6.3% to 39.3%; with variation between in-hospital (6.3-39.3%) versus out-of-hospital (18.9-21.2%) cardiac arrest. Individual variables regarding patient characteristics demonstrated statistically significant association with propensity for near-death experiences. Reported content of near-death experiences tended to reflect the language of the questionnaires used, rather than the true language used by individual study participants. Three studies conducted follow-up, and all suggested a positive life attitude change, however one found significantly higher 30-day all-cause mortality in patients with near-death experiences versus those without, in non-controlled analysis. CONCLUSIONS From prospective studies that have investigated the phenomenon, near-death experiences may occur in as frequent as over one-third of patients with cardiac arrest. Lasting effects may follow these events, however these could also be confounded by clinical characteristics.
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Affiliation(s)
- Joshua G Kovoor
- University of Adelaide, Adelaide, South Australia, Australia
- Ballarat Base Hospital, Ballarat, VIC, Australia
- Royal Adelaide Hospital, Adelaide, South Australia, Australia
- Health and Information, Adelaide, South Australia, Australia
- Heart of the Nation, Sydney, NSW, Australia
| | | | - Brandon Stretton
- University of Adelaide, Adelaide, South Australia, Australia
- Royal Adelaide Hospital, Adelaide, South Australia, Australia
- Health and Information, Adelaide, South Australia, Australia
| | - Sheryn Tan
- University of Adelaide, Adelaide, South Australia, Australia
- Health and Information, Adelaide, South Australia, Australia
| | - Hasti Gouldooz
- Gold Coast University Hospital, Gold Coast, QLD, Australia
| | | | | | - Christopher Hannemann
- Ballarat Base Hospital, Ballarat, VIC, Australia
- Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Long Kiu Yu
- University of Adelaide, Adelaide, South Australia, Australia
| | - Rhys Johnson
- University of Adelaide, Adelaide, South Australia, Australia
| | - Benjamin A Reddi
- University of Adelaide, Adelaide, South Australia, Australia
- Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Aashray K Gupta
- University of Adelaide, Adelaide, South Australia, Australia
- Health and Information, Adelaide, South Australia, Australia
- Gold Coast University Hospital, Gold Coast, QLD, Australia
| | - Morganne Wagner
- State University of New York Upstate Medical University, Syracuse, NY, USA
| | | | - Pramesh Kovoor
- Heart of the Nation, Sydney, NSW, Australia
- Westmead Hospital, Sydney, NSW, Australia
- University of Sydney, Sydney, NSW, Australia
| | - Tarun Bastiampillai
- Flinders University, Adelaide, South Australia, Australia
- Flinders Medical Centre, Adelaide, South Australia, Australia
| | - Ian Maddocks
- Australasian Chapter of Palliative Medicine, Royal Australasian College of Physicians, Adelaide, South Australia, Australia
| | - Seth W Perry
- State University of New York Upstate Medical University, Syracuse, NY, USA
| | - Ma-Li Wong
- State University of New York Upstate Medical University, Syracuse, NY, USA
| | - Julio Licinio
- State University of New York Upstate Medical University, Syracuse, NY, USA
- Flinders University, Adelaide, South Australia, Australia
| | - Stephen Bacchi
- Health and Information, Adelaide, South Australia, Australia.
- Flinders University, Adelaide, South Australia, Australia.
- Lyell McEwin Hospital, Adelaide, South Australia, Australia.
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8
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Thomas D, O'Connor G. Exploring near death experiences with children post intensive care: A case series. Explore (NY) 2024; 20:443-449. [PMID: 38016826 DOI: 10.1016/j.explore.2023.11.003] [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: 09/15/2023] [Revised: 11/03/2023] [Accepted: 11/08/2023] [Indexed: 11/30/2023]
Abstract
Near death experiences (NDEs) can occur during life-threatening events. In this article, we present preliminary findings from a case study series. We highlight experiences of children that are synchronous with the basic elements of near death experiences (NDEs) and discuss how children describe their own experiences. Children reported unsolicited NDE type experiences that included out of body experiences, bright lights, bedside visions, bi-location and visiting celestial places. The aim of the article is to show that children are an important research population for the study of near-death experiences. Children's near-death experiences are simple and carry transcendental features such as a peaceful darkness, a knowing awareness and time alterations. Children assign a subjective reality to their near-death experiences. Younger children may demonstrate a visual NDE semiosis which warrants further investigation. The aim of the article is to demonstrate the value for involving children in NDE research through participatory and creative research methods.
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Affiliation(s)
- Donna Thomas
- IcreateS Research Unit, University of Central Lancashire, UK, Floor 1, Eden House, Preston, United Kingdom.
| | - Graeme O'Connor
- Great Ormand Street Children's Hospital Foundation Trust, Great Ormand Street, London, United Kingdom
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9
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Jiang Y, Sleigh J. Consciousness and General Anesthesia: Challenges for Measuring the Depth of Anesthesia. Anesthesiology 2024; 140:313-328. [PMID: 38193734 DOI: 10.1097/aln.0000000000004830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2024]
Abstract
The optimal consciousness level required for general anesthesia with surgery is unclear, but in existing practice, anesthetic oblivion, may be incomplete. This article discusses the concept of consciousness, how it is altered by anesthetics, the challenges for assessing consciousness, currently used technologies for assessing anesthesia levels, and future research directions. Wakefulness is marked by a subjective experience of existence (consciousness), perception of input from the body or the environment (connectedness), the ability for volitional responsiveness, and a sense of continuity in time. Anesthetic drugs may selectively impair some of these components without complete extinction of the subjective experience of existence. In agreement with Sanders et al. (2012), the authors propose that a state of disconnected consciousness is the optimal level of anesthesia, as it likely avoids both awareness and the possible dangers of oversedation. However, at present, there are no reliably tested indices that can discriminate between connected consciousness, disconnected consciousness, and complete unconsciousness.
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Affiliation(s)
- Yandong Jiang
- Department of Anesthesiology, Critical Care and Pain Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas
| | - Jamie Sleigh
- Department of Anesthesiology, University of Auckland, Hamilton, New Zealand
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10
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Marchetti G. The self and conscious experience. Front Psychol 2024; 15:1340943. [PMID: 38333065 PMCID: PMC10851942 DOI: 10.3389/fpsyg.2024.1340943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2023] [Accepted: 01/04/2024] [Indexed: 02/10/2024] Open
Abstract
The primary determinant of the self (S) is the conscious experience (CE) we have of it. Therefore, it does not come as a surprise that empirical research on S mainly resorts to the CE (or lack of CE) that subjects have of their S. What comes as a surprise is that empirical research on S does not tackle the problem of how CE contributes to building S. Empirical research investigates how S either biases the cognitive processing of stimuli or is altered through a wide range of means (meditation, hypnosis, etc.). In either case, even for different reasons, considerations of how CE contributes to building S are left unspecified in empirical research. This article analyzes these reasons and proposes a theoretical model of how CE contributes to building S. According to the proposed model, the phenomenal aspect of consciousness is produced by the modulation-engendered by attentional activity-of the energy level of the neural substrate (that is, the organ of attention) that underpins attentional activity. The phenomenal aspect of consciousness supplies the agent with a sense of S and informs the agent on how its S is affected by the agent's own operations. The phenomenal aspect of consciousness performs its functions through its five main dimensions: qualitative, quantitative, hedonic, temporal, and spatial. Each dimension of the phenomenal aspect of consciousness can be explained by a specific aspect of the modulation of the energy level of the organ of attention. Among other advantages, the model explains the various forms of S as outcomes resulting from the operations of a single mechanism and provides a unifying framework for empirical research on the neural underpinnings of S.
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Affiliation(s)
- Giorgio Marchetti
- Mind, Consciousness and Language Research Center, Alano di Piave, Italy
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11
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Li Y, Chen Y, Martial C, Shen M, Cassol H, Yu J, Zhou X, Ni C, Li M, Hu N, Gosseries O, Laureys S, Di H. Chinese translation and validation of the Near-Death Experience Content scale. Front Psychiatry 2024; 14:1201416. [PMID: 38268557 PMCID: PMC10806053 DOI: 10.3389/fpsyt.2023.1201416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 12/26/2023] [Indexed: 01/26/2024] Open
Abstract
Introduction In recent years, a growing number of near-death experience (NDE) testimonies have been collected worldwide due to an increasing interest in research on this phenomenon. China has many patients who survive life-threatening situations, leaving over much data on NDEs to be collected for research. In the historical context of Eastern civilization, many mentally controlled practices in China can also lead to "NDEs-like" (e.g., meditation). This study aimed (1) to translate and validate the recently developed Near-Death Experience Content (NDE-C) scale into Chinese and (2) to quantify and identify NDEs and NDEs-like in China with this new Chinese version of the NDE-C scale. Methods Here, we presented the work that had been performed to translate the NDE-C scale into Chinese and validated this version on 79 NDE testimonies. Results Brislin's back-translation model was performed to translate a Chinese version of the NDE-C scale and internal consistency (the Cronbach's α value for the total group = 0.846) as well as the confirmatory factor analysis was conducted. Discussion Currently, the Chinese version of the NDE-C scale is ready for use in research practice in the context of Eastern culture, to screen people who have experienced an NDEs(-like) and to quantify their subjective experience, promoting further NDEs-related research in China.
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Affiliation(s)
- Yan Li
- International Vegetative State and Consciousness Science Institute, Hangzhou Normal University, Hangzhou, China
| | - Yan Chen
- International Vegetative State and Consciousness Science Institute, Hangzhou Normal University, Hangzhou, China
| | - Charlotte Martial
- Coma Science Group, GIGA-Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
| | - Mingquan Shen
- International Vegetative State and Consciousness Science Institute, Hangzhou Normal University, Hangzhou, China
| | - Héléna Cassol
- Coma Science Group, GIGA-Consciousness, University of Liège, Liège, Belgium
| | - Jing Yu
- International Vegetative State and Consciousness Science Institute, Hangzhou Normal University, Hangzhou, China
| | - Xingyue Zhou
- International Vegetative State and Consciousness Science Institute, Hangzhou Normal University, Hangzhou, China
| | - Chengcheng Ni
- International Vegetative State and Consciousness Science Institute, Hangzhou Normal University, Hangzhou, China
| | - Meiqi Li
- International Vegetative State and Consciousness Science Institute, Hangzhou Normal University, Hangzhou, China
| | - Nantu Hu
- International Vegetative State and Consciousness Science Institute, Hangzhou Normal University, Hangzhou, China
| | - Olivia Gosseries
- Coma Science Group, GIGA-Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
| | - Steven Laureys
- Coma Science Group, GIGA-Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
- Joint International Research Unit on Consciousness, CERVO Brain Research Centre, Laval University, Québec, QC, Canada
| | - Haibo Di
- International Vegetative State and Consciousness Science Institute, Hangzhou Normal University, Hangzhou, China
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12
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Montupil J, Cardone P, Staquet C, Bonhomme A, Defresne A, Martial C, Alnagger NL, Gosseries O, Bonhomme V. The nature of consciousness in anaesthesia. BJA OPEN 2023; 8:100224. [PMID: 37780201 PMCID: PMC10539891 DOI: 10.1016/j.bjao.2023.100224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 08/28/2023] [Indexed: 10/03/2023]
Abstract
Neuroscientists agree on the value of locating the source of consciousness within the brain. Anaesthesiologists are no exception, and have their own operational definition of consciousness based on phenomenological observations during anaesthesia. The full functional correlates of consciousness are yet to be precisely identified, however rapidly evolving progress in this scientific domain has yielded several theories that attempt to model the generation of consciousness. They have received variable support from experimental observations, including those involving anaesthesia and its ability to reversibly modulate different aspects of consciousness. Aside from the interest in a better understanding of the mechanisms of consciousness, exploring the functional tenets of the phenomenological consciousness states of general anaesthesia has the potential to ultimately improve patient management. It could facilitate the design of specific monitoring devices and approaches, aiming at reliably detecting each of the possible states of consciousness during an anaesthetic procedure, including total absence of mental content (unconsciousness), and internal awareness (sensation of self and internal thoughts) with or without conscious perception of the environment (connected or disconnected consciousness, respectively). Indeed, it must be noted that unresponsiveness is not sufficient to infer absence of connectedness or even absence of consciousness. This narrative review presents the current knowledge in this field from a system-level, underlining the contribution of anaesthesia studies in supporting theories of consciousness, and proposing directions for future research.
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Affiliation(s)
- Javier Montupil
- Anesthesia and Perioperative Neuroscience Laboratory, Liege, Belgium
- Department of Anesthesia and Intensive Care Medicine, Liege, Belgium
- University Department of Anesthesia and Intensive Care Medicine, Citadelle Regional Hospital, Liege, Belgium
| | - Paolo Cardone
- Coma Science Group, GIGA-Consciousness Thematic Unit, GIGA-Research, Liege University, Liege, Belgium
- Centre du Cerveau, Liege University Hospital, Liege, Belgium
| | - Cécile Staquet
- Anesthesia and Perioperative Neuroscience Laboratory, Liege, Belgium
- Department of Anesthesia and Intensive Care Medicine, Liege, Belgium
| | - Arthur Bonhomme
- Coma Science Group, GIGA-Consciousness Thematic Unit, GIGA-Research, Liege University, Liege, Belgium
| | - Aline Defresne
- Anesthesia and Perioperative Neuroscience Laboratory, Liege, Belgium
- Department of Anesthesia and Intensive Care Medicine, Liege, Belgium
- University Department of Anesthesia and Intensive Care Medicine, Citadelle Regional Hospital, Liege, Belgium
| | - Charlotte Martial
- Coma Science Group, GIGA-Consciousness Thematic Unit, GIGA-Research, Liege University, Liege, Belgium
- Centre du Cerveau, Liege University Hospital, Liege, Belgium
| | - Naji L.N. Alnagger
- Coma Science Group, GIGA-Consciousness Thematic Unit, GIGA-Research, Liege University, Liege, Belgium
- Centre du Cerveau, Liege University Hospital, Liege, Belgium
| | - Olivia Gosseries
- Coma Science Group, GIGA-Consciousness Thematic Unit, GIGA-Research, Liege University, Liege, Belgium
- Centre du Cerveau, Liege University Hospital, Liege, Belgium
| | - Vincent Bonhomme
- Anesthesia and Perioperative Neuroscience Laboratory, Liege, Belgium
- Department of Anesthesia and Intensive Care Medicine, Liege, Belgium
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Martial C, Cassol H, Slater M, Bourdin P, Mensen A, Oliva R, Laureys S, Núñez P. Electroencephalographic Signature of Out-of-Body Experiences Induced by Virtual Reality: A Novel Methodological Approach. J Cogn Neurosci 2023; 35:1410-1422. [PMID: 37255451 DOI: 10.1162/jocn_a_02011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Out-of-body experiences (OBEs) are subjective experiences of seeing one's own body and the environment from a location outside the physical body. They can arise spontaneously or in specific conditions, such as during the intake of dissociative drug. Given its unpredictable occurrence, one way to empirically study it is to induce subjective experiences resembling an OBE using technology such as virtual reality. We employed a complex multisensory method of virtual embodiment in a virtual reality scenario with seven healthy participants to induce virtual OBE-like experiences. Participants performed two conditions in a randomly determined order. For both conditions, the participant's viewpoint was lifted out of the virtual body toward the ceiling of the virtual room, and real body movements were (visuo-tactile ON condition) or were not (visuo-tactile OFF condition) translated into movements on the virtual body below-the latter aiming to maintain a feeling of connection with the virtual body. A continuous 128-electrode EEG was recorded. Participants reported subjective experiences of floating in the air and of feeling high up in the virtual room at a strong intensity, but a weak to moderate feeling of being "out of their body" in both conditions. The EEG analysis revealed that this subjective experience was associated with a power shift that manifested in an increase of delta and a decrease of alpha relative power. A reduction of theta complexity and an increase of beta-2 connectivity were also found. This supports the growing body of evidence revealing a prominent role of delta activity during particular conscious states.
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Affiliation(s)
| | | | - Mel Slater
- University of Barcelona, Spain
- Institute of Neurosciences of the University of Barcelona, Spain
| | - Pierre Bourdin
- University of Barcelona, Spain
- Open University of Catalonia, Spain
| | | | | | - Steven Laureys
- University of Liège, Belgium
- University Hospital of Liège, Belgium
- University Laval, Québec, Canada
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Panda R, Vanhaudenhuyse A, Piarulli A, Annen J, Demertzi A, Alnagger N, Chennu S, Laureys S, Faymonville ME, Gosseries O. Altered Brain Connectivity and Network Topological Organization in a Non-ordinary State of Consciousness Induced by Hypnosis. J Cogn Neurosci 2023; 35:1394-1409. [PMID: 37315333 DOI: 10.1162/jocn_a_02019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Hypnosis has been shown to be of clinical utility; however, its underlying neural mechanisms remain unclear. This study aims to investigate altered brain dynamics during the non-ordinary state of consciousness induced by hypnosis. We studied high-density EEG in 9 healthy participants during eyes-closed wakefulness and during hypnosis, induced by a muscle relaxation and eyes fixation procedure. Using hypotheses based on internal and external awareness brain networks, we assessed region-wise brain connectivity between six ROIs (right and left frontal, right and left parietal, upper and lower midline regions) at the scalp level and compared across conditions. Data-driven, graph-theory analyses were also carried out to characterize brain network topology in terms of brain network segregation and integration. During hypnosis, we observed (1) increased delta connectivity between left and right frontal, as well as between right frontal and parietal regions; (2) decreased connectivity for alpha (between right frontal and parietal and between upper and lower midline regions) and beta-2 bands (between upper midline and right frontal, frontal and parietal, also between upper and lower midline regions); and (3) increased network segregation (short-range connections) in delta and alpha bands, and increased integration (long-range connections) in beta-2 band. This higher network integration and segregation was measured bilaterally in frontal and right parietal electrodes, which were identified as central hub regions during hypnosis. This modified connectivity and increased network integration-segregation properties suggest a modification of the internal and external awareness brain networks that may reflect efficient cognitive-processing and lower incidences of mind-wandering during hypnosis.
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Affiliation(s)
| | | | | | - Jitka Annen
- University of Liège, Belgium
- University Hospital of Liège, Belgium
| | | | - Naji Alnagger
- University of Liège, Belgium
- University Hospital of Liège, Belgium
| | | | - Steven Laureys
- University of Liège, Belgium
- University Hospital of Liège, Belgium
- Laval University, Québec, Canada
| | | | - Olivia Gosseries
- University of Liège, Belgium
- University Hospital of Liège, Belgium
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Sanz LR, Laureys S, Gosseries O. Towards modern post-coma care based on neuroscientific evidence. Int J Clin Health Psychol 2023; 23:100370. [PMID: 36817874 PMCID: PMC9932483 DOI: 10.1016/j.ijchp.2023.100370] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Accepted: 01/12/2023] [Indexed: 02/05/2023] Open
Abstract
Background Understanding the mechanisms underlying human consciousness is pivotal to improve the prognostication and treatment of severely brain-injured patients. Consciousness remains an elusive concept and the identification of its neural correlates is an active subject of research, however recent neuroscientific advances have allowed scientists to better characterize disorders of consciousness. These breakthroughs question the historical nomenclature and our current management of post-comatose patients. Method This review examines the contribution of consciousness neurosciences to the current clinical management of severe brain injury. It investigates the major impact of consciousness disorders on healthcare systems, the scientific frameworks employed to identify their neural correlates and how evidence-based data from neuroimaging research have reshaped the landscape of post-coma care in recent years. Results Our increased ability to detect behavioral and neurophysiological signatures of consciousness has led to significant changes in taxonomy and clinical practice. We advocate for a multimodal framework for the management of severely brain-injured patients based on precision medicine and evidence-based decisions, integrating epidemiology, health economics and neuroethics. Conclusions Major progress in brain imaging and clinical assessment have opened the door to a new era of post-coma care based on standardized neuroscientific evidence. We highlight its implications in clinical applications and call for improved collaborations between researchers and clinicians to better translate findings to the bedside.
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Affiliation(s)
- Leandro R.D. Sanz
- Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
| | - Steven Laureys
- Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
- Joint International Research Unit on Consciousness, CERVO Brain Research Centre, CIUSS, Laval University, Québec, Canada
| | - Olivia Gosseries
- Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
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Michael P, Luke D, Robinson O. This is your brain on death: a comparative analysis of a near-death experience and subsequent 5-Methoxy-DMT experience. Front Psychol 2023; 14:1083361. [PMID: 37457069 PMCID: PMC10345338 DOI: 10.3389/fpsyg.2023.1083361] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 05/02/2023] [Indexed: 07/18/2023] Open
Abstract
Introduction Much research has focused on the modeling of the near-death experience (NDE) by classical and atypical psychedelics; however, to date, no study has reported on the relationship between the NDE and the experience induced by the highly potent, endogenous psychedelic drug 5-Methoxy-DMT (5MeO-DMT). This article presents a case study of an individual who is popularly documented to have had a profound near-death experience while in a coma caused by bacterial meningoencephalitis. Additionally, the individual also subsequently underwent an experience with 5MeO-DMT. Methods A semi-structured interview was conducted with the subject concerning his experiences with both the NDE and 5MeO-DMT. A basic thematic analysis was performed on both the original text describing the NDE as well as the interview itself, which mainly focused on the subject's experience with 5MeO-DMT. This analysis was organized to identify both the similar and different emergent themes between the two states, with a particular emphasis on the subject's perceptions of the similarities and differences between the experiences. Results There is a very high level of comparability between the original NDE and psychedelic experiences in general, including shared characteristics such as entering other worlds, meeting menacing or benevolent entities, experiencing synesthesia, perinatal regression, and lucid dreamlike properties. Much comparability was also identified with the 5MeO-DMT experience, in particular the major mystical experiential domains, such as ego dissolution, but especially transcendence of time and space. However, there were also a few unique themes (life review, the deceased, and the threshold) that emerged in the NDE that were not present in the 5MeO-DMT experience or other psychedelic experience studies, suggesting that these themes may be more unique to the NDE. Discussion Despite such similarities, the participant asserted that his NDE and psychedelic experiences were not similar enough to be attributed to endogenous psychedelics. In this study, we discussed several mechanisms that could potentially account for the NDE, including lucid dreams and perinatal regression. However, the study also explored the possibility that the unique etiology of the participant's NDE, bacterial meningoencephalitis affecting the neocortex, may have triggered similar downstream neural activity as that initiated by psychedelic agents through pyramidal neuronal activation. This hypothesis is presented with appropriate caveats and acknowledged as speculative.
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Affiliation(s)
- Pascal Michael
- Centre for Mental Health, School of Human Sciences, Old Royal Naval College, University of Greenwich, London, United Kingdom
| | - David Luke
- Centre for Mental Health, School of Human Sciences, Old Royal Naval College, University of Greenwich, London, United Kingdom
- Centre for Psychedelic Research, Department of Brain Sciences, Faculty of Medicine, Imperial College, London, United Kingdom
| | - Oliver Robinson
- Centre for Mental Health, School of Human Sciences, Old Royal Naval College, University of Greenwich, London, United Kingdom
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Shlobin NA, Aru J, Vicente R, Zemmar A. What happens in the brain when we die? Deciphering the neurophysiology of the final moments in life. Front Aging Neurosci 2023; 15:1143848. [PMID: 37228251 PMCID: PMC10203241 DOI: 10.3389/fnagi.2023.1143848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 04/12/2023] [Indexed: 05/27/2023] Open
Abstract
When do we die and what happens in the brain when we die? The mystery around these questions has engaged mankind for centuries. Despite the challenges to obtain recordings of the dying brain, recent studies have contributed to better understand the processes occurring during the last moments of life. In this review, we summarize the literature on neurophysiological changes around the time of death. Perhaps the only subjective description of death stems from survivors of near-death experiences (NDEs). Hallmarks of NDEs include memory recall, out-of-body experiences, dreaming, and meditative states. We survey the evidence investigating neurophysiological changes of these experiences in healthy subjects and attempt to incorporate this knowledge into the existing literature investigating the dying brain to provide valuations for the neurophysiological footprint and timeline of death. We aim to identify reasons explaining the variations of data between studies investigating this field and provide suggestions to standardize research and reduce data variability.
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Affiliation(s)
- Nathan A. Shlobin
- Department of Neurosurgery, Henan Provincial People’s Hospital, Henan University School of Medicine, Zhengzhou, China
- Department of Neurological Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Jaan Aru
- Institute of Computer Science, University of Tartu, Tartu, Estonia
| | - Raul Vicente
- Institute of Computer Science, University of Tartu, Tartu, Estonia
| | - Ajmal Zemmar
- Department of Neurosurgery, Henan Provincial People’s Hospital, Henan University School of Medicine, Zhengzhou, China
- Department of Neurological Surgery, University of Louisville School of Medicine, Louisville, KY, United States
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Michael P, Luke D, Robinson O. An encounter with the self: A thematic and content analysis of the DMT experience from a naturalistic field study. Front Psychol 2023; 14:1083356. [PMID: 37051610 PMCID: PMC10083325 DOI: 10.3389/fpsyg.2023.1083356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 02/22/2023] [Indexed: 03/28/2023] Open
Abstract
IntroductionN,N-Dimethyltryptamine (DMT) is an endogenous serotonergic psychedelic capable of producing radical shifts in an experience that have significant implications for consciousness and its neural correlates, especially given the “disconnected consciousness” suggested by the “breakthrough” DMT state. Its increasing usage and clinical trial indicate the growing importance of a thorough elucidation of the experience's qualitative content, over and above the phenomenological structure. This is particularly in light of the intensely pervasive effects of DMT occasions in all dimensions of the self, which are often ontologically challenging yet potentially transformative.MethodsThis is the second report on the first naturalistic field study of DMT use exploring its qualitative analysis. Screened, healthy, anonymized, and experienced DMT users were observed during their non-clinical use of the drug at home (40–75-mg inhaled). In-depth semi-structured interviews, inspired by the micro-phenomenological technique, were employed immediately after their experience. This study reports on the thematic and content analysis of one major domain of the breakthrough experiences elicited, the “self”; where analyses of the “other” were previously reported. A total of 36 post-DMT experience interviews with mostly Caucasian (83%) men (eight women) of a mean of 37 years were predominantly inductively coded.ResultsInvariably, profound and highly intense experiences occurred. The first overarching category comprised the onset of effects, encompassing super-ordinate themes including sensory, emotion and body, and space-time shifts; the second category comprised bodily effects, encompassing themes including pleasurable, neutral/both, and uncomfortable; the third category comprised the sensorial effects, encompassing open-eye, visual, and cross-modal and other; the fourth comprised the psychological effects, encompassing memory and language, awareness and sense of self, and time distortions; and the fifth comprised the emotional effects, encompassing positive, neither/both, and challenging experiences. Many further subthemes also illuminate the rich content of the DMT experience.DiscussionThe present study provides a systematic and nuanced analysis of the content of the breakthrough DMT state pertaining to one's personal and self-referential experiences of the body, senses, psychology, and emotions. The resonances both with previous DMT studies and other types of extraordinary experiences, such as the alien abduction, shamanic and near-death experiences, are also elaborated upon. Putative neural mechanisms and their promise as a psychotherapeutic agent, especially owing to deep emotional impact, are discussed.
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Affiliation(s)
- Pascal Michael
- Centre for Mental Health, School of Human Sciences, Old Royal Naval College, University of Greenwich, London, United Kingdom
| | - David Luke
- Centre for Mental Health, School of Human Sciences, Old Royal Naval College, University of Greenwich, London, United Kingdom
- Department of Brain Sciences, Faculty of Medicine, Centre for Psychedelic Research, Imperial College London, London, United Kingdom
| | - Oliver Robinson
- Centre for Mental Health, School of Human Sciences, Old Royal Naval College, University of Greenwich, London, United Kingdom
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Lapses of the Heart: Frequency and Subjective Salience of Impressions Reported by Patients after Cardiac Arrest. J Clin Med 2023; 12:jcm12051968. [PMID: 36902754 PMCID: PMC10004426 DOI: 10.3390/jcm12051968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 02/16/2023] [Accepted: 02/27/2023] [Indexed: 03/06/2023] Open
Abstract
After cardiac arrest (CA), some patients report impressions with highly realistic features, often referred to as near-death experience (NDE). The frequency of such episodes seems to be variable, with various types of content. In a prospective study, we subjected 126 CA cases treated at the Department of Emergency Medicine of the Medical University of Vienna under carefully controlled conditions to a structured interview. We included all patients admitted due to CA, whose communicative abilities were restored and who agreed to participate in the study. The questionnaire inquired as to living conditions, attitudes towards issues of life and death, and last recollections before and first impressions after the CA. The majority of the subjects (91 = 76%) replied to inquiries concerning impressions during CA with "nothing" or "blackout", but 20 (16%) gave a detailed account. A German version of the Greyson questionnaire specifically addressing NDE phenomena (included towards the end of the interview) resulted in ≥7 points in five patients (4%). Three patients reported a meeting with deceased relatives (one with 6 Greyson points), one an out-of-body episode, and one having been sucked into a colorful tunnel. Eleven of these twenty cases had their cardiopulmonary resuscitation (CPR) started within the first min of CA, a higher fraction than cases without experience. Reported experience after CA was of high significance for the patients; many of them changed their point of view on issues of life and death.
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Rousseau AF, Dams L, Massart Q, Choquer L, Cassol H, Laureys S, Misset B, Dardenne N, Gosseries O, Martial C. Incidence of near-death experiences in patients surviving a prolonged critical illness and their long-term impact: a prospective observational study. Crit Care 2023; 27:76. [PMID: 36849984 PMCID: PMC9969623 DOI: 10.1186/s13054-023-04348-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 02/06/2023] [Indexed: 03/01/2023] Open
Abstract
BACKGROUND So far, the few prospective studies on near-death experience (NDE) were carried out only in intensive care unit (ICU) patients with homogeneous aetiologies, such as cardiac arrest or trauma survivors. The aims of this 1-year prospective and monocentric study were to investigate the incidence of NDE in ICU survivors (all aetiologies) as well as factors that may affect its frequency, and to assess quality of life up to 1 year after enrolment. METHODS We enrolled adults with a prolonged ICU stay (> 7 days). During the first 7 days after discharge, all eligible patients were assessed in a face-to-face interview for NDE using the Greyson NDE scale, dissociative experiences using the Dissociative Experience Scale, and spirituality beliefs using the WHOQOL-SRPB. Medical parameters were prospectively collected. At 1-year after inclusion, patients were contacted by phone to measure quality of life using the EuroQol five-dimensional questionnaire. RESULTS Out of the 126 included patients, 19 patients (15%) reported having experienced a NDE as identified by the Greyson NDE scale (i.e. cut-off score ≥ 7/32). In univariate analyses, mechanical ventilation, sedation, analgesia, reason for admission, primary organ dysfunction, dissociative and spiritual propensities were associated with the emergence of NDE. In multivariate logistic regression analysis, only the dissociative and spiritual propensity strongly predicted the emergence of NDE. One year later (n = 61), the NDE was not significantly associated with quality of life. CONCLUSIONS The recall of NDE is not so rare in the ICU. In our cohort, cognitive and spiritual factors outweighed medical parameters as predictors of the emergence of NDE. Trial registration This trial was registered in Clinicaltrials.gov in February 2020 ( NCT04279171 ).
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Affiliation(s)
- Anne-Françoise Rousseau
- grid.4861.b0000 0001 0805 7253Department of Intensive Care and Burn Centre, University Hospital of Liège, University of Liège, Liège, Belgium
| | - Laurence Dams
- grid.4861.b0000 0001 0805 7253Department of Anaesthesiology, University Hospital of Liège, University of Liège, Liège, Belgium
| | - Quentin Massart
- grid.4861.b0000 0001 0805 7253Department of Anaesthesiology, University Hospital of Liège, University of Liège, Liège, Belgium
| | - Laila Choquer
- grid.4861.b0000 0001 0805 7253Department of Anaesthesiology, University Hospital of Liège, University of Liège, Liège, Belgium
| | - Héléna Cassol
- grid.4861.b0000 0001 0805 7253Coma Science Group, GIGA-Consciousness, University of Liège, Avenue de L’hôpital, 11, 4000 Liège, Belgium ,grid.411374.40000 0000 8607 6858Centre du Cerveau², University Hospital of Liège, Liège, Belgium
| | - Steven Laureys
- grid.4861.b0000 0001 0805 7253Coma Science Group, GIGA-Consciousness, University of Liège, Avenue de L’hôpital, 11, 4000 Liège, Belgium ,grid.411374.40000 0000 8607 6858Centre du Cerveau², University Hospital of Liège, Liège, Belgium ,grid.23856.3a0000 0004 1936 8390Joint International Research Unit On Consciousness, CERVO Brain Research Centre, CIUSS, University Laval, Québec, Canada
| | - Benoit Misset
- grid.4861.b0000 0001 0805 7253Department of Intensive Care and Burn Centre, University Hospital of Liège, University of Liège, Liège, Belgium
| | - Nadia Dardenne
- grid.4861.b0000 0001 0805 7253University and Hospital Biostatistics Centre (B-STAT), University of Liège, Liège, Belgium
| | - Olivia Gosseries
- grid.4861.b0000 0001 0805 7253Coma Science Group, GIGA-Consciousness, University of Liège, Avenue de L’hôpital, 11, 4000 Liège, Belgium ,grid.411374.40000 0000 8607 6858Centre du Cerveau², University Hospital of Liège, Liège, Belgium ,grid.4861.b0000 0001 0805 7253Sensation and Perception Research Group, GIGA-Consciousness, University of Liège, Liege, Belgium
| | - Charlotte Martial
- Coma Science Group, GIGA-Consciousness, University of Liège, Avenue de L'hôpital, 11, 4000, Liège, Belgium. .,Centre du Cerveau², University Hospital of Liège, Liège, Belgium.
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Romand R, Ehret G. Neuro-functional modeling of near-death experiences in contexts of altered states of consciousness. Front Psychol 2023; 13:846159. [PMID: 36743633 PMCID: PMC9891231 DOI: 10.3389/fpsyg.2022.846159] [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: 01/10/2022] [Accepted: 11/23/2022] [Indexed: 01/19/2023] Open
Abstract
Near-death experiences (NDEs) including out-of-body experiences (OBEs) have been fascinating phenomena of perception both for affected persons and for communities in science and medicine. Modern progress in the recording of changing brain functions during the time between clinical death and brain death opened the perspective to address and understand the generation of NDEs in brain states of altered consciousness. Changes of consciousness can experimentally be induced in well-controlled clinical or laboratory settings. Reports of the persons having experienced the changes can inform about the similarity of the experiences with those from original NDEs. Thus, we collected neuro-functional models of NDEs including OBEs with experimental backgrounds of drug consumption, epilepsy, brain stimulation, and ischemic stress, and included so far largely unappreciated data from fighter pilot tests under gravitational stress generating cephalic nervous system ischemia. Since we found a large overlap of NDE themes or topics from original NDE reports with those from neuro-functional NDE models, we can state that, collectively, the models offer scientifically appropriate causal explanations for the occurrence of NDEs. The generation of OBEs, one of the NDE themes, can be localized in the temporo-parietal junction (TPJ) of the brain, a multimodal association area. The evaluated literature suggests that NDEs may emerge as hallucination-like phenomena from a brain in altered states of consciousness (ASCs).
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Affiliation(s)
- Raymond Romand
- Faculty of Medicine, University of Strasbourg, Strasbourg, France,*Correspondence: Raymond Romand,
| | - Günter Ehret
- Institute of Neurobiology, University of Ulm, Ulm, Germany,Günter Ehret,
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Scholkmann F, Vollenweider FX. Psychedelics and fNIRS neuroimaging: exploring new opportunities. NEUROPHOTONICS 2023; 10:013506. [PMID: 36474478 PMCID: PMC9717437 DOI: 10.1117/1.nph.10.1.013506] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 11/14/2022] [Indexed: 06/17/2023]
Abstract
In this Outlook paper, we explain to the optical neuroimaging community as well as the psychedelic research community the great potential of using optical neuroimaging with functional near-infrared spectroscopy (fNIRS) to further explore the changes in brain activity induced by psychedelics. We explain why we believe now is the time to exploit the momentum of the current resurgence of research on the effects of psychedelics and the momentum of the increasing progress and popularity of the fNIRS technique to establish fNIRS in psychedelic research. With this article, we hope to contribute to this development.
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Affiliation(s)
- Felix Scholkmann
- University Hospital Zurich, University of Zurich, Biomedical Optics Research Laboratory, Department of Neonatology, Zurich, Switzerland
- University of Bern, Institute of Complementary and Integrative Medicine, Bern, Switzerland
| | - Franz X. Vollenweider
- University Hospital of Psychiatry, University of Zurich, Neuropsychopharmacology and Brain Imaging, Department of Psychiatry, Psychotherapy and Psychosomatics, Zurich, Switzerland
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Bicego A, Cassol H, Simon J, Fritz P, Abagnale S, Vanhaudenhuyse A, Laureys S, Martial C. Personality traits and pattern of beliefs of near-death(-like) experiencers. Front Hum Neurosci 2023; 17:1124739. [PMID: 37187942 PMCID: PMC10175626 DOI: 10.3389/fnhum.2023.1124739] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 03/17/2023] [Indexed: 05/17/2023] Open
Abstract
Introduction Little is known about the potential personality and psychological predictors of near-death experiences (NDEs), and fewer yet those of near-death-like experiences (NDEs-like; similar phenomenology reported after a non-life-threatening context). This study investigated whether personality traits (Openness, Extraversion, Pleasantness, Conscientiousness, and Neuroticism), dissociative experiences, Fantasy proneness, disposition toward auditory hallucinations, absorption trait, and endorsement of paranormal and spiritual beliefs could be associated with the recall of NDEs(-like). Methods To this aim, we invited four groups of people to retrospectively fill in questionnaires assessing the following factors: NDE experiencers (n = 63), NDE(-like) experiencers (n = 31), controls with a life-threatening situation but no NDE(-like) (n = 43), and controls without a life-threatening situation or an NDE(-like) (n = 44). We carried out univariate analyses for each factor and then performed a multiple regression analysis and a discriminant analysis. Results The multivariate logistic regression analysis revealed that the endorsement of spiritual beliefs was associated with the recall of NDEs-like while Openness and Fantasy proneness were associated with the recall of NDEs. The discriminant analysis showed that these variables produce 35% of correct classification. Discussion Albeit retrospective, these results pave the way for future research on psychological predictors of NDEs(-like) by highlighting the influence of Spirituality, Openness, and Fantasy proneness on these phenomena.
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Affiliation(s)
- Aminata Bicego
- Sensation and Perception Research Group, GIGA-Consciousness, University of Liège, Liège, Belgium
| | - Héléna Cassol
- Neurological and Functional Rehabilitation Center, University Hospital of Liège, Fraiture, Belgium
- Coma Science Group, GIGA-Consciousness, University of Liège, Liège, Belgium
| | - Jessica Simon
- Psychology and Neuroscience of Cognition Research Unit (PsyNCog), University of Liège, Liège, Belgium
| | - Pauline Fritz
- Coma Science Group, GIGA-Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
| | - Simona Abagnale
- Coma Science Group, GIGA-Consciousness, University of Liège, Liège, Belgium
| | - Audrey Vanhaudenhuyse
- Sensation and Perception Research Group, GIGA-Consciousness, University of Liège, Liège, Belgium
- Interdisciplinary Algology Centre, University Hospital of Liège, Liège, Belgium
| | - Steven Laureys
- Coma Science Group, GIGA-Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
- CERVO Brain Research Center, University of Laval, Québec, QC, Canada
| | - Charlotte Martial
- Coma Science Group, GIGA-Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
- *Correspondence: Charlotte Martial
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24
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Marchetti G. The why of the phenomenal aspect of consciousness: Its main functions and the mechanisms underpinning it. Front Psychol 2022; 13:913309. [PMID: 35967722 PMCID: PMC9368316 DOI: 10.3389/fpsyg.2022.913309] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 07/01/2022] [Indexed: 12/02/2022] Open
Abstract
What distinguishes conscious information processing from other kinds of information processing is its phenomenal aspect (PAC), the-what-it-is-like for an agent to experience something. The PAC supplies the agent with a sense of self, and informs the agent on how its self is affected by the agent’s own operations. The PAC originates from the activity that attention performs to detect the state of what I define “the self” (S). S is centered and develops on a hierarchy of innate and acquired values, and is primarily expressed via the central and peripheral nervous systems; it maps the agent’s body and cognitive capacities, and its interactions with the environment. The detection of the state of S by attention modulates the energy level of the organ of attention (OA), i.e., the neural substrate that underpins attention. This modulation generates the PAC. The PAC can be qualified according to five dimensions: qualitative, quantitative, hedonic, temporal and spatial. Each dimension can be traced back to a specific feature of the modulation of the energy level of the OA.
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25
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Chirico A, Pizzolante M, Kitson A, Gianotti E, Riecke BE, Gaggioli A. Defining Transformative Experiences: A Conceptual Analysis. Front Psychol 2022; 13:790300. [PMID: 35814064 PMCID: PMC9263695 DOI: 10.3389/fpsyg.2022.790300] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 05/06/2022] [Indexed: 11/21/2022] Open
Abstract
The concept of transformative experience (TE) has been widely explored by several disciplines from philosophy to neurobiology, and in different domains, from the spiritual to the educational one. This attitude has engendered heterogeneous models to explain this phenomenon. However, a consistent and clear understanding of this construct remains elusive. The aim of this work is to provide an initial comprehensive interdisciplinary, cross-domain, up-to-date, and integrated overview on the concept of TEs. Firstly, all the models and theories on TEs were reviewed to extract and analyze TEs’ main components emerging from different disciplines. Then, this preliminary analysis was integrated with an in-depth examination of redundancies and particularities across domains and disciplines, to provide an integrated theoretical framework of TEs and a preliminary interdisciplinary operational definition of TEs. This examination, in turn, can help organize current research and theories, thus providing suggestions for operationalizing TEs as well as encouraging new interdisciplinary research endeavors.
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Affiliation(s)
- Alice Chirico
- Department of Psychology, Research Center in Communication Psychology, Universitá Cattolica del Sacro Cuore, Milan, Italy
- *Correspondence: Alice Chirico,
| | - Marta Pizzolante
- Department of Psychology, Research Center in Communication Psychology, Universitá Cattolica del Sacro Cuore, Milan, Italy
| | - Alexandra Kitson
- School of Interactive Arts and Technology (SIAT), Simon Fraser University, Surrey, BC, Canada
| | - Elena Gianotti
- Department of Psychology, Universitá Cattolica del Sacro Cuore, Milan, Italy
| | - Bernhard E. Riecke
- School of Interactive Arts and Technology (SIAT), Simon Fraser University, Surrey, BC, Canada
| | - Andrea Gaggioli
- Department of Psychology, Research Center in Communication Psychology, Universitá Cattolica del Sacro Cuore, Milan, Italy
- Applied Technology for Neuro-Psychology Lab, I.R.C.C.S. Istituto Auxologico Italiano, Milan, Italy
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26
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Vicente R, Rizzuto M, Sarica C, Yamamoto K, Sadr M, Khajuria T, Fatehi M, Moien-Afshari F, Haw CS, Llinas RR, Lozano AM, Neimat JS, Zemmar A. Enhanced Interplay of Neuronal Coherence and Coupling in the Dying Human Brain. Front Aging Neurosci 2022; 14:813531. [PMID: 35273490 PMCID: PMC8902637 DOI: 10.3389/fnagi.2022.813531] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 01/19/2022] [Indexed: 11/13/2022] Open
Abstract
The neurophysiological footprint of brain activity after cardiac arrest and during near-death experience (NDE) is not well understood. Although a hypoactive state of brain activity has been assumed, experimental animal studies have shown increased activity after cardiac arrest, particularly in the gamma-band, resulting from hypercapnia prior to and cessation of cerebral blood flow after cardiac arrest. No study has yet investigated this matter in humans. Here, we present continuous electroencephalography (EEG) recording from a dying human brain, obtained from an 87-year-old patient undergoing cardiac arrest after traumatic subdural hematoma. An increase of absolute power in gamma activity in the narrow and broad bands and a decrease in theta power is seen after suppression of bilateral hemispheric responses. After cardiac arrest, delta, beta, alpha and gamma power were decreased but a higher percentage of relative gamma power was observed when compared to the interictal interval. Cross-frequency coupling revealed modulation of left-hemispheric gamma activity by alpha and theta rhythms across all windows, even after cessation of cerebral blood flow. The strongest coupling is observed for narrow- and broad-band gamma activity by the alpha waves during left-sided suppression and after cardiac arrest. Albeit the influence of neuronal injury and swelling, our data provide the first evidence from the dying human brain in a non-experimental, real-life acute care clinical setting and advocate that the human brain may possess the capability to generate coordinated activity during the near-death period.
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Affiliation(s)
- Raul Vicente
- Department of Neurosurgery, Henan Provincial People’s Hospital, Henan University People’s Hospital, Henan University School of Medicine, Zhengzhou, China
- Institute of Computer Science, University of Tartu, Tartu, Estonia
| | - Michael Rizzuto
- Division of Neurosurgery, Department of Surgery, Vancouver General Hospital, University of British Columbia, Vancouver, BC, Canada
| | - Can Sarica
- Division of Neurosurgery, Department of Surgery, Toronto Western Hospital, University of Toronto, Toronto, ON, Canada
| | - Kazuaki Yamamoto
- Division of Neurosurgery, Department of Surgery, Toronto Western Hospital, University of Toronto, Toronto, ON, Canada
| | - Mohammed Sadr
- Division of Neurosurgery, Department of Surgery, Vancouver General Hospital, University of British Columbia, Vancouver, BC, Canada
| | - Tarun Khajuria
- Institute of Computer Science, University of Tartu, Tartu, Estonia
| | - Mostafa Fatehi
- Division of Neurosurgery, Department of Surgery, Vancouver General Hospital, University of British Columbia, Vancouver, BC, Canada
| | - Farzad Moien-Afshari
- Epilepsy Program, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Charles S. Haw
- Division of Neurosurgery, Department of Surgery, Vancouver General Hospital, University of British Columbia, Vancouver, BC, Canada
| | - Rodolfo R. Llinas
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, NY, United States
| | - Andres M. Lozano
- Division of Neurosurgery, Department of Surgery, Toronto Western Hospital, University of Toronto, Toronto, ON, Canada
| | - Joseph S. Neimat
- Department of Neurosurgery, School of Medicine, University of Louisville, Louisville, KY, United States
| | - Ajmal Zemmar
- Department of Neurosurgery, Henan Provincial People’s Hospital, Henan University People’s Hospital, Henan University School of Medicine, Zhengzhou, China
- Division of Neurosurgery, Department of Surgery, Toronto Western Hospital, University of Toronto, Toronto, ON, Canada
- Department of Neurosurgery, School of Medicine, University of Louisville, Louisville, KY, United States
- *Correspondence: Ajmal Zemmar,
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27
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Walter J. Consciousness as a multidimensional phenomenon: implications for the assessment of disorders of consciousness. Neurosci Conscious 2021; 2021:niab047. [PMID: 34992792 PMCID: PMC8716840 DOI: 10.1093/nc/niab047] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 10/19/2021] [Accepted: 12/10/2021] [Indexed: 01/10/2023] Open
Abstract
Disorders of consciousness (DoCs) pose a significant clinical and ethical challenge because they allow for complex forms of conscious experience in patients where intentional behaviour and communication are highly limited or non-existent. There is a pressing need for brain-based assessments that can precisely and accurately characterize the conscious state of individual DoC patients. There has been an ongoing research effort to develop neural measures of consciousness. However, these measures are challenging to validate not only due to our lack of ground truth about consciousness in many DoC patients but also because there is an open ontological question about consciousness. There is a growing, well-supported view that consciousness is a multidimensional phenomenon that cannot be fully described in terms of the theoretical construct of hierarchical, easily ordered conscious levels. The multidimensional view of consciousness challenges the utility of levels-based neural measures in the context of DoC assessment. To examine how these measures may map onto consciousness as a multidimensional phenomenon, this article will investigate a range of studies where they have been applied in states other than DoC and where more is known about conscious experience. This comparative evidence suggests that measures of conscious level are more sensitive to some dimensions of consciousness than others and cannot be assumed to provide a straightforward hierarchical characterization of conscious states. Elevated levels of brain complexity, for example, are associated with conscious states characterized by a high degree of sensory richness and minimal attentional constraints, but are suboptimal for goal-directed behaviour and external responsiveness. Overall, this comparative analysis indicates that there are currently limitations to the use of these measures as tools to evaluate consciousness as a multidimensional phenomenon and that the relationship between these neural signatures and phenomenology requires closer scrutiny.
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Affiliation(s)
- Jasmine Walter
- Cognition and Philosophy Lab, 21 Chancellor’s Walk, Monash University, Melbourne, VIC 3800, Australia
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28
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Portnova GV. Resting-state network activity revealed by EEG in unresponsive hospice patients at the end of life. Clin Neurophysiol 2021; 135:162-163. [PMID: 34952804 DOI: 10.1016/j.clinph.2021.12.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 12/06/2021] [Indexed: 11/17/2022]
Affiliation(s)
- Galina V Portnova
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, 5A Butlerova St., Moscow, 117485, Russia.
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29
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Annen J, Panda R, Martial C, Piarulli A, Nery G, Sanz LRD, Valdivia-Valdivia JM, Ledoux D, Gosseries O, Laureys S. Mapping the functional brain state of a world champion freediver in static dry apnea. Brain Struct Funct 2021; 226:2675-2688. [PMID: 34420066 DOI: 10.1007/s00429-021-02361-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 08/04/2021] [Indexed: 11/27/2022]
Abstract
Voluntary apnea showcases extreme human adaptability in trained individuals like professional free divers. We evaluated the psychological and physiological adaptation and the functional cerebral changes using electroencephalography (EEG) and functional Magnetic Resonance Imaging (fMRI) to 6.5 min of dry static apnea performed by a world champion free diver. Compared to resting state at baseline, breath holding was characterized by increased EEG power and functional connectivity in the alpha band, along with decreased delta band connectivity. fMRI connectivity was increased within the default mode network (DMN) and visual areas but decreased in pre- and postcentral cortices. While these changes occurred in regions overlapping with cerebral signatures of several meditation practices, they also display some unique features that suggest an altered somatosensory integration. As suggested by self-reports, these findings could reflect the ability of elite free divers to create a state of sensory dissociation when performing prolonged apnea.
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Affiliation(s)
- Jitka Annen
- Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium.
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium.
| | - Rajanikant Panda
- Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
| | - Charlotte Martial
- Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
| | - Andrea Piarulli
- Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium
- Department of Surgical, Medical, Molecular and Critical Area Pathology, University of Pisa, Pisa, Italy
| | | | - Leandro R D Sanz
- Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
| | - Juan M Valdivia-Valdivia
- Department of Neurosurgery. St, Joseph's Hospital, Tampa, FL, USA
- International Association for Development of Apnea (AIDA International), Medical and Science Committee, Zurich, Switzerland
| | - Didier Ledoux
- Anesthesia and Intensive Care, GIGA Consciousness, ULiège, Liège, Belgium
- Intensive Care Department, University Hospital of Liège, Liège, Belgium
| | - Olivia Gosseries
- Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
| | - Steven Laureys
- Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
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30
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Losing the Self in Near-Death Experiences: The Experience of Ego-Dissolution. Brain Sci 2021; 11:brainsci11070929. [PMID: 34356163 PMCID: PMC8307473 DOI: 10.3390/brainsci11070929] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/30/2021] [Accepted: 07/08/2021] [Indexed: 12/12/2022] Open
Abstract
Many people who have had a near-death experience (NDE) describe, as part of it, a disturbed sense of having a “distinct self”. However, no empirical studies have been conducted to explore the frequency or intensity of these effects. We surveyed 100 NDE experiencers (Near-Death-Experience Content [NDE-C] scale total score ≥27/80). Eighty participants had their NDEs in life-threatening situations and 20 had theirs not related to life-threatening situations. Participants completed the Ego-Dissolution Inventory (EDI) and the Ego-Inflation Inventory (EII) to assess the experience of ego dissolution and inflation potentially experienced during their NDE, respectively. They also completed the Nature-Relatedness Scale (NR-6) which measures the trait-like construct of one’s self-identification with nature. Based on prior hypotheses, ratings of specific NDE-C items pertaining to out-of-body experiences and a sense of unity were used for correlational analyses. We found higher EDI total scores compared with EII total scores in our sample. Total scores of the NDE-C scale were positively correlated with EDI total scores and, although less strongly, the EII and NR-6 scores. EDI total scores were also positively correlated with the intensity of OBE and a sense of unity. This study suggests that the experience of dissolved ego-boundaries is a common feature of NDEs.
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31
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The Near-Death Experience Content (NDE-C) scale: Development and psychometric validation. Conscious Cogn 2020; 86:103049. [PMID: 33227590 DOI: 10.1016/j.concog.2020.103049] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 11/05/2020] [Accepted: 11/05/2020] [Indexed: 02/06/2023]
Abstract
As interest grows in near-death experiences (NDEs), it is increasingly important to accurately identify them to facilitate empirical research and reproducibility among assessors. We aimed (1) to reassess the psychometric properties of the NDE scale developed by Greyson (1983) and (2) to validate the Near-Death Experience Content (NDE-C) scale that quantifies NDEs in a more complete way. Internal consistency, construct and concurrent validity analyses were performed on the NDE scale. Based on those results and the most recent empirical evidence, we then developed a new 20-item scale. Internal consistency, explanatory and confirmatory factor, concurrent and discriminant validity analyses were conducted. Results revealed (1) a series of weaknesses in the NDE scale, (2) a 5-factor structure covering relevant dimensions and the very good psychometric properties of the NDE-C scale, including very good internal consistency (Cronbach α = 0.85) and concurrent validity (correlations above 0.76). This new reliable scale should facilitate future research.
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32
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Abstract
The self is a multifaceted phenomenon that manifests in a complex configuration of character traits, roles, orientations, and other psychological components. The entity that is binding these subcomponents together has mostly eluded systematic enquiry. In an effort to approach this Gestalt-like whole in an empirical manner, we here introduce the concept of the “peripheral self”: the moments of growth and expansion where the current self grows beyond the horizon of already successful mastery. Over the course of 1 year, we have pursued an empirical first-person approach to explore this continuously shifting horizon of self-development. Our main result is a collection of signature qualities—“experiential echoes”—that demarcate the peripheral self as it advances from potentiality to conscious insight. We provide a roadmap for other researchers to follow up on this approach and relate our findings to the still sparse literature on what constitutes the overarching character of the self.
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Affiliation(s)
- Ulrich Weger
- Department of Psychology, Witten/Herdecke University, Witten, Germany
| | - Klaus Herbig
- Psychotherapeutische Praxis Herbig, Zurich, Switzerland
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33
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Bond GD, Pasko B, Solis-Perez F, Sisneros CS, Gonzales AF, Bargo AJB, Walker WR. Remembering the Super-Typhoon: Some, but Not All, Qualities of First-Hand Survivor Memories of Natural Disaster Are Similar to Near Death Experience and Flashbulb Memory Accounts. Psychol Rep 2020; 124:2119-2138. [PMID: 32954974 DOI: 10.1177/0033294120957570] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The strongest storm in Philippines history, super-typhoon Haiyan, barreled through central Philippines in 2013 and left a high death toll and extensive destruction in its wake. Past studies have investigated Fading Affect Bias (FAB) in extremely negative situations like the death of a loved one and found that the FAB generally occurs in those extreme situations, but this study is the first to assess FAB in first-hand memories for a natural disaster survival situation. The FAB phenomenon is the tendency for emotional intensity associated with negative memories for events to fade over time and emotional intensity for positive events stays relatively stable over time. Researchers collected memories for the super-typhoon from survivors three years after the event. Results showed that negative emotional intensity for the event faded after the event. Emotion in comparison positive memories for non-typhoon events did not fade, and emotion in comparison negative memories faded, following results in several other FAB studies. The Positive and Negative Affect Scale (PANAS) was used as an initial assessment of mood before the study began, and PANAS scores reliably predicted current emotional intensity scores. Memory vividness and emotional intensity in first-hand accounts of a natural disaster experience behave like vividness and intensity in flashbulb memories, but details in first-hand accounts are similar to the amount of details in memories of near-death experiences. How memory rehearsal behaves in relation to time elapsed since event has yet to be captured for first-hand survival experiences.
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Affiliation(s)
- Gary D Bond
- Department of Psychological Sciences, Eastern New Mexico University, Portales, NM, USA.,Department of Psychology, Colorado State University-Pueblo, Pueblo, CO, USA
| | - Brian Pasko
- Department of Mathematical Sciences, Eastern New Mexico University, Portales, NM, USA.,Department of Psychology, Colorado State University-Pueblo, Pueblo, CO, USA
| | | | | | - Angelina F Gonzales
- Department of Psychological Sciences, Eastern New Mexico University, Portales, NM, USA.,Department of Psychology, Colorado State University-Pueblo, Pueblo, CO, USA
| | - Ann J B Bargo
- Department of Education, Capiz State University, Roxas City, Capiz, Philippines.,Department of Psychology, Colorado State University-Pueblo, Pueblo, CO, USA
| | - W Richard Walker
- Department of Psychology, Colorado State University-Pueblo, Pueblo, CO, USA
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34
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Akiyama T, Hirata T, Fujimoto T, Hatakeyama S, Yamazaki R, Nomura T. The Natural-Mineral-Based Novel Nanomaterial IFMC Increases Intravascular Nitric Oxide without Its Intake: Implications for COVID-19 and beyond. NANOMATERIALS 2020; 10:nano10091699. [PMID: 32872395 PMCID: PMC7559745 DOI: 10.3390/nano10091699] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 08/16/2020] [Accepted: 08/27/2020] [Indexed: 01/22/2023]
Abstract
There are currently no promising therapy strategies for either the treatment or prevention of novel coronavirus disease 2019 (COVID-19), despite the urgent need. In addition to respiratory diseases, vascular complications are rapidly emerging as a key threat of COVID-19. Existing nitric oxide (NO) therapies have been shown to improve the vascular system; however, they have different limitations in terms of safety, usability and availability. In light of this, we hypothesise that a natural-mineral-based novel nanomaterial, which was developed based on NO therapy, might be a viable strategy for the treatment and prevention of COVID-19. The present study examined if it could induce an increase of intravascular NO, vasodilation and the consequent increase of blood flow rate and temperature in a living body. The intravascular NO concentration in the hepatic portal of rats was increased by 0.17 nM over 35.2 s on average after its application. An ultrasonic Doppler flow meter showed significant increases in the blood flow rate and vessel diameter, but no difference in the blood flow velocity. These were corroborated by measurements of human hand surface temperature. To our knowledge, this result is the first evidence where an increase of intravascular NO and vasodilation were induced by bringing a natural-mineral-based nanomaterial into contact with or close to a living body. The precise mechanisms remain a matter for further investigation; however, we may assume that endothelial NO synthase, haemoglobin and endothelium-derived hyperpolarising factor are deeply involved in the increase of intravascular NO.
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Affiliation(s)
- Tomohiro Akiyama
- Advanced Research Laboratories, Tokyo City University, Tokyo 158-8557, Japan;
- Graduate School of Information Technology, Kobe Institute of Computing, Kobe 650-0001, Japan
- Graduate School of Education, Kyoto University, Kyoto 606-8501, Japan
- Graduate School of Global Environmental Studies, Sophia University, Tokyo 102-8554, Japan
- Correspondence: (T.A.); (T.H.)
| | - Takamichi Hirata
- Advanced Research Laboratories, Tokyo City University, Tokyo 158-8557, Japan;
- Graduate School of Integrative Science and Engineering, Electrical Engineering and Chemistry, Tokyo City University, Tokyo 158-8557, Japan; (S.H.); (R.Y.)
- Correspondence: (T.A.); (T.H.)
| | - Takahiro Fujimoto
- Advanced Research Laboratories, Tokyo City University, Tokyo 158-8557, Japan;
- Clinic F Laser Medicine & Surgery, Tokyo 102-0083, Japan
| | - Shinnosuke Hatakeyama
- Graduate School of Integrative Science and Engineering, Electrical Engineering and Chemistry, Tokyo City University, Tokyo 158-8557, Japan; (S.H.); (R.Y.)
| | - Ryuhei Yamazaki
- Graduate School of Integrative Science and Engineering, Electrical Engineering and Chemistry, Tokyo City University, Tokyo 158-8557, Japan; (S.H.); (R.Y.)
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35
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Kondziella D. The Neurology of Death and the Dying Brain: A Pictorial Essay. Front Neurol 2020; 11:736. [PMID: 32793105 PMCID: PMC7385288 DOI: 10.3389/fneur.2020.00736] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 06/15/2020] [Indexed: 01/18/2023] Open
Abstract
As neurologists earn their living with the preservation and restoration of brain function, they are also well-positioned to address the science behind the transition from life to death. This essay in pictures highlights areas of neurological expertise needed for brain death determination; shows pitfalls to avoid during the clinical examination and interpretation of confirmatory laboratory tests in brain death protocols; illustrates the great variability of brain death legislations around the world; discusses arguments for the implementation of donation after circulatory death (DCD); points to unresolved questions related to DCD and the time between cardiac standstill and organ procurement (“hands-off period”); provides an overview of the epidemiology and semiology of near-death experiences, including their importance for religion, literature, and the visual arts; suggests biological mechanisms for near-death experiences such as dysfunction of temporoparietal cortex, N-methyl-D-aspartate receptor antagonism, migraine aura, and rapid eye movement sleep; hypothesizes that thanatosis (aka. death-feigning, a common behavioral trait in the animal kingdom) represents the evolutionary origin of near-death experiences; and speculates about the future implications of recent attempts of brain resuscitation in an animal model. The aim is to provide the reader with a thorough understanding that the boundaries within the neurology of death and the dying brain are being pushed just like everywhere else in the clinical neurosciences.
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Affiliation(s)
- Daniel Kondziella
- Department of Neurology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.,Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
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