Consciousness after death

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This article is about the neuroscience of consciousness and death. For beliefs about life after death, see Afterlife.

The question of consciousness after death is a common theme in society and culture in the context of life after death. Scientific research has established that the mind and normal waking consciousness are closely connected with the physiological functioning of the brain, the cessation of which defines brain death. However, many people believe in some form of life after death, which is a feature of many religions.

Neuroscience[edit]

Neuroscience is a large interdisciplinary field founded on the premise that all of behavior and all of the cognitive processes that constitute the mind have their origin in the structure and function of the nervous system, especially in the brain. According to this view, the mind can be regarded as a set of operations carried out by the brain.[1][2][3][4][5]

There are multiple lines of evidence that support this view. They are here briefly summarized along with some examples.

Pharmacological manipulation using various drugs which alter neural activity by interfering with neurotransmission, resulting in alterations in perception, mood, consciousness, cognition, and behavior. Psychoactive drugs are divided into different groups according to their pharmacological effects; euphoriants which tend to induce feelings of euphoria, stimulants that induce temporary improvements in either mental or physical functions, depressants that depress or reduce arousal or stimulation and hallucinogens which can cause hallucinations, perception anomalies, and other substantial subjective changes in thoughts, emotion, and consciousness.
Electrical and magnetical stimulations using various electrical methods and techniques like transcranial magnetic stimulation. In a comprehensive review of electrical brain stimulation (EBS) results obtained from the last 100 years neuroscientist Aslihan Selimbeyoglu and neurologist Josef Parvizi compiled a list of many different subjective experiential phenomena and behavioral changes that can be caused by electrical stimulation of the cerebral cortex or subcortical nuclei in awake and conscious human subjects.[9]
Optogenetic manipulation where light is used to control neurons which have been genetically sensitised to light.

Death[edit]

Main article: Death

Death was once defined as the cessation of heartbeat (cardiac arrest) and of breathing, but the development of CPR and prompt defibrillation have rendered that definition inadequate because breathing and heartbeat can sometimes be restarted. Events which were causally linked to death in the past no longer kill in all circumstances; without a functioning heart or lungs, life can sometimes be sustained with a combination of life support devices, organ transplants and artificial pacemakers.

Today, where a definition of the moment of death is required, doctors and coroners usually turn to "brain death" or "biological death" to define a person as being dead; brain death being defined as the complete and irreversible loss of brain function (including involuntary activity necessary to sustain life).[15][16][17][18] According to the current neuroscientific view, consciousness fails to survive brain death and ceases to exist.[19][20]

Near-death experiences (NDEs)[edit]

A near-death experience (NDE) refers to a personal experience associated with impending death, encompassing multiple possible sensations including detachment from the body, feelings of levitation, total serenity, security, warmth, the experience of absolute dissolution, and the presence of a light.[21][22]

Explanatory models for the NDE can be divided into several broad categories, including psychological, physiological, and transcendental explanations.[23][24][25] Research from neuroscience explains the NDE in terms of various physiological and psychological factors,[26] while some NDE researchers in the field of near-death studies advocate for a transcendental explanation.[27][28]

See also[edit]

References[edit]

  1. ^ Kandel, ER; Schwartz JH; Jessell TM; Siegelbaum SA; Hudspeth AJ. "Principles of Neural Science, Fifth Edition" (2012).
  2. ^ Squire, L. et al. "Fundamental Neuroscience, 4th edition" (2012).
  3. ^ O. Carter Snead. "Neuroimaging and the "Complexity" of Capital Punishment" (2007).
  4. ^ Eric R. Kandel, M.D. "A New Intellectual Framework for Psychiatry" (1998).
  5. ^ "Neuroscience Core Concepts: The Essential Principles of Neuroscience". BrainFacts.org: Explore the Brain and Mind. 
  6. ^ Farah, Martha J.; Murphy, Nancey (February 2009). "Neuroscience and the Soul". Science 323 (5918): p. 1168. doi:10.1126/science.323.5918.1168a. Retrieved 20 November 2012. 
  7. ^ Max Velmans, Susan Schneider. "The Blackwell Companion to Consciousness" (2008). p. 560.
  8. ^ Matt Carter, Jennifer C. Shieh. "Guide to Research Techniques in Neuroscience" (2009).
  9. ^ Aslihan Selimbeyoglu, Josef Parvizi. "Electrical stimulation of the human brain: perceptual and behavioral phenomena reported in the old and new literature" (2010). Frontiers in Human Neuroscience.
  10. ^ "Severe TBI Symptoms"
  11. ^ "Symptoms of Brain Injury"
  12. ^ "Cognitive Development and Aging: A Life Span Perspective"
  13. ^ "Adolescent Brains Are A Work In Progress"
  14. ^ "Blossoming brains"
  15. ^ "Brain death". Encyclopedia of Death and Dying. Retrieved 25 March 2014. 
  16. ^ Young, G Bryan. "Diagnosis of brain death". UpToDate. Retrieved 25 March 2014. 
  17. ^ Goila, A.; Pawar, M. (2009). "The diagnosis of brain death". Indian Journal of Critical Care Medicine 13 (1): 7–11. doi:10.4103/0972-5229.53108. PMC 2772257. PMID 19881172.  edit
  18. ^ Machado, C. (2010). "Diagnosis of brain death". Neurology International 2. doi:10.4081/ni.2010.e2.  edit
  19. ^ Laureys, Steven; Tononi, Giulio. (2009). The Neurology of Consciousness: Cognitive Neuroscience and Neuropathology. Academic Press. p. 20. ISBN 978-0-12-374168-4
  20. ^ Piccinini, Gualtiero; Bahar, Sonya. "No Mental Life after Brain Death: The Argument from the Neural Localization of Mental Functions" (2011). University of Missouri - St. Louis.
  21. ^ Roberts, Glenn; Owen, John. (1988). The Near-Death Experience. British Journal of Psychiatry 153: 607-617.
  22. ^ Britton, Willoughby B. and Richard R. Bootzin. (2004). Near-Death Experiences and the Temporal Lobe. Psychological Science. Vol. 15, No. 4. pp. 254-258.
  23. ^ Linda J. Griffith. "Near-Death Experiences and Psychotherapy" (2009).
  24. ^ Mauro, James. Bright lights, big mystery. Psychology Today, July 1992
  25. ^ Vanhaudenhuyse, A; Thonnard, M; Laureys, S. "Towards a Neuro-scientific Explanation of Near-death Experiences?" (2009).
  26. ^ Olaf Blanke, Sebastian Dieguez. "Leaving Body and Life Behind: Out-of-Body and Near-Death Experience" (2009).
  27. ^ Sam Parnia, Peter Fenwick. "Near death experiences in cardiac arrest: visions of a dying brain or visions of a new science of consciousness" (2001).
  28. ^ Murray, Craig D. (2009). Psychological Scientific Perspectives on Out-of-Body and Near-Death Experiences. New York: Nova Science Publishers. pp. 187–203. ISBN 978-1-60741-705-7. 

Further reading[edit]