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Near Death Experiences (NDE). Presented by Jennifer Kwok Jennifer Tom Luong Phan. What is the near death experience?. Occurs when a person enters “clinical death” and usually has a profound personal experience which can include:. What is the near death experience?.
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Near Death Experiences(NDE) Presented by Jennifer Kwok Jennifer Tom Luong Phan
What is the near death experience? • Occurs when a person enters “clinical death” and usually has a profound personal experience which can include:
What is the near death experience? • Occurs when a person enters “clinical death” and usually has a profound personal experience which can include: • A sensation of leaving the body
What is the near death experience? • Occurs when a person enters “clinical death” and usually has a profound personal experience which can include: • A sensation of leaving the body • Following a bright light
What is the near death experience? • Occurs when a person enters “clinical death” and usually has a profound personal experience which can include: • A sensation of leaving the body • Following a bright light • Encounter with a higher being (God, Buddha, Aliens, etc.)
Background Information • What is “clinical death” then?
Background Information • What is “clinical death” then? • Clinical death: no cardiac output, no respiration, fixed dilated pupils
Background Information • What is “clinical death” then? • Clinical death: no cardiac output, no respiration, fixed dilated pupils • Focus of our research evidence are centered on cardiac arrest patients because they all exhibit clinical death
Background Information • Raymond Moody (1975) • Wrote Life After Life • First compilation of NDE survivor stories • Coined the term “near death experience”
Background Information • Why care about NDE? • NDE have been recorded through history and in many different cultures. • Description of Er’s experience in Plato’s Republic resemble modern NDEs. • Best chance to study death because these patients return from “dying”
Theorized Causes • Disturbance of brain chemistry (Parnia 2001) • alpha-endopsychosin, hypoxia, NDMA, etc.
Theorized Causes • Disturbance of brain chemistry (Parnia 2001) • alpha-endopsychosin, hypoxia, NDMA, etc. • Psychological response to perceived threat of death (Parnia 2001) • Wish fulfillment in response to perceived threat of death
Theorized Causes • REM intrusion (Nelson 2006) • When things normally experienced during sleep carry over into wakefulness
Theorized Causes • REM intrusion (Nelson 2006) • When things normally experienced during sleep carry over into wakefulness • Usually occurs before sleep or just after wakefulness
Theorized Causes • REM intrusion (Nelson 2006) • When things normally experienced during sleep carry over into wakefulness • Usually occurs before sleep or just after wakefulness • Occurs in times of extreme stress in which one may be in REM sleep and partially awake at the same time
Theorized Causes: REM Int. Cont’ • REM centers in the brainstem • Higher brain areas in the cortex quickly blank out during hypoxia, the brainstem (since it’s more primitive) remains active for several minutes
Theorized Causes: REM Int. Cont’ • REM centers in the brainstem • Higher brain areas in the cortex quickly blank out during hypoxia, the brainstem (since it’s more primitive) remains active for several minutes • An NDE that seems to last many minutes might occur in the few seconds right before or right after the cortex blanks out
Theorized Causes: REM Int. Cont’ • REM centers in the brainstem • Higher brain areas in the cortex quickly blank out during hypoxia, the brainstem (since it’s more primitive) remains active for several minutes • An NDE that seems to last many minutes might occur in the few seconds right before or right after the cortex blanks out • NDE may also be very brief but be perceived as prolong because REM compresses time
Theorized Causes: REM Int. Cont’ • Vagus nerve: A cranial nerve that connects the brainstem to the heart and lungs • REM intrusion and the vagus nerve (Fox 2006) • In times of extreme stress (heart attacks or near drowning) blood pressure or blood oxygen levels quickly drop, or levels of carbon dioxide in the blood quickly rise. • This stimulates the vague nerve • Since the REM centers are in the brainstem, this causes the REM centers to snap on without warning
Theorized Causes: REM Int. Cont’ • Evidence for vagus nerve in REM intrusion (Fox 2006) • Animal studies • When electrically stimulating the vagus nerve in various animal preparations, stimulation enhances REM and causes atonia • Stimulating the vagus nerve in cats pushes them into REM sleep within 45 seconds • Human studies • Epilepsy patients whose condition is treated with implants stimulate their vagus nerve also slip more quickly into REM during daytime naps
Theorized Causes: REM Int. Cont’ • Temporal-parietal junction (Fox 2006) • Known to cause out-of-body sensations when it malfunctions • Since it is located at the end of a tree of blood vessels, if blood pressure drops, perfusion in this area is first to go • Thus if blood pressure drops when one is fainting, this explains why they may experience NDE-like symptoms
Theorized Causes: REM Int. Cont’ • Could be possible that NDE enhances subsequent REM intrusion • SUPPORTED by: people with Post Traumatic Stress Disorder subsequently have more frequent REM intrusion
Evidence: REM intrusion and NDE • REM intrusion during wakefulness is a normal occurrence but infrequently recognized (Nelson 2005)
Evidence: REM intrusion and NDE • REM intrusion during wakefulness is a normal occurrence but infrequently recognized (Nelson 2005) • Underlies other clinical conditions such as narcolepsy
Evidence: REM intrusion and NDE • Common feature of narcolepsy • Neurological disorder characterized by uncontrollable bouts of sleep that can cause elaborate hallucinations and out-of-body experiences
Evidence: REM intrusion and NDE • Common feature of narcolepsy • Neurological disorder characterized by uncontrollable bouts of sleep that can cause elaborate hallucinations and out-of-body experiences • Narcoleptics’ REM systems can activate leading to out of body experiences
Evidence: REM intrusion and NDE • Common feature of narcolepsy • Neurological disorder characterized by uncontrollable bouts of sleep that can cause elaborate hallucinations and out-of-body experiences • Narcoleptics’ REM systems can activate leading to out of body experiences • Combination of dreaming and wakefulness causes people with narcolepsy to recall their hallucinations vividly
Evidence: REM intrusion and NDE • Another form of REM intrusion is sleep paralysis • Awaken with part of brain still in REM sleep so body feel paralyzed • Result: terrified that you’re unable to move, visual/auditory hallucinations, and pressure on the chest
Evidence: REM intrusion and NDE • Nelson: surveyed of REM intrusion: 55 people who had NDE from a variety of situations and 55 controls matched for age and gender • Found that around 60% of NDE group reported having experiencing some kind of symptoms of REM intrusion, either before or after their NDE, compared with just 24 % of the control • REM intrusions in NDE group were more elaborate (not just sleep paralysis but also hallucinations
Evidence: REM intrusion and NDE • Nelson: surveyed of REM intrusion: 55 people who had NDE from a variety of situations and 55 controls matched for age and gender • Not conclusive but good preliminary correlational experience • Not conclusive because possible that REM intrusion makes you more susceptible to NDE; also suggests that you do not need to have a near-death experience to have NDE
Why NDE is an ASC • NDE is a deviation from the normal waking state • Experience clinical death • Experience another reality • Large population can experience NDE • Prevalence of REM intrusion • 10% cardiac arrest patients develop memories consistent with NDE • What about the other 90%? Still experience but don’t remember?
References Bosveld, Jane. "Soul Search: Can Science Ever Decipher the Secrets of the Human Soul?" Discover magazine, June 2007. Fox, Douglas. "Light at the End of the Tunnel." New Scientist. Retrieved from the web, http://www.newscientist.com, 2008 March 3. Nelson, Kevin R., MD et al (2006). Does the arousal system contribute to near death experience? Neurology, 66:1003-1009. Parnia, Sam et al (2001). A qualitative and quantitative study of the incidence, features and aetiology of near death experiences in cardiac arrest survivors. Resuscitation, 48:149-156. Parnia, Sam and Peter Fenwick (2002). Near death experiences in cardiac arrest: visions of a dying brain or visions of a new science of consciousness. Resuscitation, 52:5-11. Wallace, Benjamin and Leslie E. Fisher. Consciousness and Behavior, Fourth Edition. Waveland Press Inc., Prospect Heights, pp. 218-220.