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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] [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, University of Michigan Medical School; Ann Arbor, MI, USA
- Center for Consciousness Science, University of Michigan Medical School; Ann Arbor, MI, USA
- Neuroscience Graduate Program, University of Michigan Medical School; Ann Arbor, MI, USA
- Department of Pharmacology, University of Michigan Medical School; Ann Arbor, MI, USA
| | - UnCheol Lee
- Department of Anesthesiology, University of Michigan Medical School; Ann Arbor, MI, USA
- Center for Consciousness Science, University of Michigan Medical School; Ann Arbor, MI, USA
| | - Dinesh Pal
- Department of Anesthesiology, University of Michigan Medical School; Ann Arbor, MI, USA
- Center for Consciousness Science, University of Michigan Medical School; Ann Arbor, MI, USA
- Neuroscience Graduate Program, University of Michigan Medical School; Ann Arbor, MI, USA
- Department of Molecular and Integrative Physiology; University of Michigan Medical School; Ann Arbor, MI, USA
| | - Duan Li
- Department of Anesthesiology, University of Michigan Medical School; Ann Arbor, MI, USA
- Center for Consciousness Science, University of Michigan Medical School; Ann Arbor, MI, USA
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Charpier S. Between life and death: the brain twilight zones. Front Neurosci 2023; 17:1156368. [PMID: 37260843 PMCID: PMC10227869 DOI: 10.3389/fnins.2023.1156368] [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: 02/01/2023] [Accepted: 04/24/2023] [Indexed: 06/02/2023] Open
Abstract
Clinically, and legally, death is considered a well-defined state of the organism characterized, at least, by a complete and irreversible cessation of brain activities and functions. According to this pragmatic approach, the moment of death is implicitly represented by a discrete event from which all cerebral processes abruptly cease. However, a growing body of experimental and clinical evidence has demonstrated that cardiorespiratory failure, the leading cause of death, causes complex time-dependent changes in neuronal activity that can lead to death but also be reversed with successful resuscitation. This review synthesizes our current knowledge of the succeeding alterations in brain activities that accompany the dying and resuscitation processes. The anoxia-dependent brain defects that usher in a process of potential death successively include: (1) a set of changes in electroencephalographic (EEG) and neuronal activities, (2) a cessation of brain spontaneous electrical activity (isoelectric state), (3) a loss of consciousness whose timing in relation to EEG changes remains unclear, (4) an increase in brain resistivity, caused by neuronal swelling, concomitant with the occurrence of an EEG deviation reflecting the neuronal anoxic insult (the so-called "wave of death," or "terminal spreading depolarization"), followed by, (5) a terminal isoelectric brain state leading to death. However, a timely restoration of brain oxygen supply-or cerebral blood flow-can initiate a mirrored sequence of events: a repolarization of neurons followed by a re-emergence of neuronal, synaptic, and EEG activities from the electrocerebral silence. Accordingly, a recent study has revealed a new death-related brain wave: the "wave of resuscitation," which is a marker of the collective recovery of electrical properties of neurons at the beginning of the brain's reoxygenation phase. The slow process of dying still represents a terra incognita, during which neurons and neural networks evolve in uncertain states that remain to be fully understood. As current event-based models of death have become neurophysiologically inadequate, I propose a new mixed (event-process) model of death and resuscitation. It is based on a detailed description of the different phases that succeed each other in a dying brain, which are generally described separately and without mechanistic linkage, in order to integrate them into a continuum of declining brain activity. The model incorporates cerebral twilight zones (with still unknown neuronal and synaptic processes) punctuated by two characteristic cortical waves providing real-time biomarkers of death- and resuscitation.
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Affiliation(s)
- Stéphane Charpier
- Sorbonne Université, Institut du Cerveau – Paris Brain Institute - ICM, Inserm, CNRS, APHP, Hôpital de la Pitié-Salpêtriére, Paris, France
- Sorbonne University, UPMC Université Paris, Paris, France
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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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Zhou Y, Sheremet A, Kennedy JP, DiCola NM, Maciel CB, Burke SN, Maurer AP. Spectrum Degradation of Hippocampal LFP During Euthanasia. Front Syst Neurosci 2021; 15:647011. [PMID: 33967707 PMCID: PMC8102791 DOI: 10.3389/fnsys.2021.647011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 03/23/2021] [Indexed: 11/13/2022] Open
Abstract
The hippocampal local field potential (LFP) exhibits a strong correlation with behavior. During rest, the theta rhythm is not prominent, but during active behavior, there are strong rhythms in the theta, theta harmonics, and gamma ranges. With increasing running velocity, theta, theta harmonics and gamma increase in power and in cross-frequency coupling, suggesting that neural entrainment is a direct consequence of the total excitatory input. While it is common to study the parametric range between the LFP and its complementing power spectra between deep rest and epochs of high running velocity, it is also possible to explore how the spectra degrades as the energy is completely quenched from the system. Specifically, it is unknown whether the 1/f slope is preserved as synaptic activity becomes diminished, as low frequencies are generated by large pools of neurons while higher frequencies comprise the activity of more local neuronal populations. To test this hypothesis, we examined rat LFPs recorded from the hippocampus and entorhinal cortex during barbiturate overdose euthanasia. Within the hippocampus, the initial stage entailed a quasi-stationary LFP state with a power-law feature in the power spectral density. In the second stage, there was a successive erosion of power from high- to low-frequencies in the second stage that continued until the only dominant remaining power was <20 Hz. This stage was followed by a rapid collapse of power spectrum toward the absolute electrothermal noise background. As the collapse of activity occurred later in hippocampus compared with medial entorhinal cortex, it suggests that the ability of a neural network to maintain the 1/f slope with decreasing energy is a function of general connectivity. Broadly, these data support the energy cascade theory where there is a cascade of energy from large cortical populations into smaller loops, such as those that supports the higher frequency gamma rhythm. As energy is pulled from the system, neural entrainment at gamma frequency (and higher) decline first. The larger loops, comprising a larger population, are fault-tolerant to a point capable of maintaining their activity before a final collapse.
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Affiliation(s)
- Yuchen Zhou
- Engineering School of Sustainable Infrastructure and Environment, University of Florida, Gainesville, FL, United States
| | - Alex Sheremet
- Engineering School of Sustainable Infrastructure and Environment, University of Florida, Gainesville, FL, United States.,Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Jack P Kennedy
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Nicholas M DiCola
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Carolina B Maciel
- Division of Neurocritical Care, Department of Neurology, University of Florida, Gainesville, FL, United States
| | - Sara N Burke
- Department of Biomedical Engineering, University of Florida, Gainesville, FL, United States
| | - Andrew P Maurer
- Engineering School of Sustainable Infrastructure and Environment, University of Florida, Gainesville, FL, United States.,Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, United States.,Department of Biomedical Engineering, University of Florida, Gainesville, FL, United States
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Idris Z, Ang SY, Wan Hassan WMN, Hassan MH, Mohd Zain KA, Abdul Manaf A. A Clinical Test for a Newly Developed Direct Brain Cooling System for the Injured Brain and Pattern of Cortical Brainwaves in Cooling, Noncooling, and Dead Brain. Ther Hypothermia Temp Manag 2021; 12:103-114. [PMID: 33513054 DOI: 10.1089/ther.2020.0033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
To ensure the direct delivery of therapeutic hypothermia at a selected constant temperature to the injured brain, a newly innovated direct brain cooling system was constructed. The practicality, effectiveness, and safety of this system were clinically tested in our initial series of 14 patients with severe head injuries. The patients were randomized into two groups: direct brain cooling at 32°C and the control group. All of them received intracranial pressure (ICP), focal brain oxygenation, brain temperature, and direct cortical brainwave monitoring. The direct brain cooling group did better in the Extended Glasgow Outcome Scale at the time of discharge and at 6 months after trauma. This could be owing to a trend in the monitored parameters; reduction in ICP, increment in cerebral perfusion pressure, optimal brain redox regulation, near-normal brain temperature, and lessening of epileptic-like brainwave activities are likely the reasons for better outcomes in the cooling group. Finally, this study depicts interesting cortical brainwaves during a transition time from being alive to dead. It is believed that the demonstrated cortical brainwaves follow the principles of quantum physics.
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Affiliation(s)
- Zamzuri Idris
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Malaysia.,Brain and Behaviour Cluster (BBC), School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Malaysia.,Hospital Universiti Sains Malaysia (HUSM), Universiti Sains Malaysia, Kubang Kerian, Malaysia
| | - Song Yee Ang
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Malaysia.,Hospital Universiti Sains Malaysia (HUSM), Universiti Sains Malaysia, Kubang Kerian, Malaysia
| | - Wan Mohd Nazaruddin Wan Hassan
- Hospital Universiti Sains Malaysia (HUSM), Universiti Sains Malaysia, Kubang Kerian, Malaysia.,Department of Anaesthesiology, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Malaysia
| | - Mohd Hasyizan Hassan
- Hospital Universiti Sains Malaysia (HUSM), Universiti Sains Malaysia, Kubang Kerian, Malaysia.,Department of Anaesthesiology, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Malaysia
| | - Khairu Anuar Mohd Zain
- Collaborative Microelectronic Design Excellence Center (CEDEC), Universiti Sains Malaysia, Bayan Lepas, Malaysia
| | - Asrulnizam Abdul Manaf
- Collaborative Microelectronic Design Excellence Center (CEDEC), Universiti Sains Malaysia, Bayan Lepas, Malaysia
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Clinique des expériences de mort imminente : du vécu agonistique aux formes extrêmes de symbolisation. EVOLUTION PSYCHIATRIQUE 2020. [DOI: 10.1016/j.evopsy.2020.04.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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