I have just finished reading a new book which has relevance to both near-death experiences and UFO abductions.
The book is "The Spiritual Doorway in the Brain: A Neurologist's search for the God Experience." The author is Kevin Nelson. Publisher is Dutton. New York. 2011. ISBN 978-0-525-95188-9.
Nelson's interest in the subject of NDEs started nearly 30 years ago when a patient he calls "Joe" had an NDE which Joe said was "absolutely real." (p.3.) Over the following years Nelson "...began to collect these stories..." (p.4.) He observed a number of medical professionals research the topic. This lead him to collect "...case studies of spiritual experiences." (p.18.)
In a chapter titled "What is a spiritual experience?" Nelson reviews the work of William James and his 1902 work "The Variety of Religious Experiences." James' work included spirituality and religion.
Central to later discussions is the subject of consciousness. Consciousness is defined in clinical neurology as "Awareness of one self and one's surroundings." (p.38.)
Nelson writes that "Within consciousness, neurology recognises three states: wakefulness; REM sleep, and non-REM sleep." (p.38.) REM is short for rapid-eye movement. Nelson's work "...has focused on the switch in the brain stem that regulates our three conscious states." (p.38.)
The three states:
"Each of the three conscious states-wakefulness, REM sleep...and non-REM sleep-has identifiable brain activity..." (p.42.)
"The nerve centres arousing the brain to respond to itself and the environment, switching the brain to sleep or wakefulness, are in the structure called the brain stem...located at the base of the skull." (p.48.)
"The arousal system contains the switches that shift our consciousness between it three states." (p.48.)
We all identify "the self' - that sense of "me." There are a number of ways in which the self can be lost. Firstly, "The Alien Arm" where your arm doesn't seem to belong to you, and moves of its own volition. "Underlying the alien limb is a disconnection from consciousness and other parts of the self..." (p.75.)
Secondly, is the rubber hand illusion. Here a person can be convinced that a lifelike but rubber hand is a part of them - their "self."
Thirdly, phantom limb pain, where an amputee can still sense their missing limb.
Fourthly, "A brainstem stroke can also cause spare limbs to sprout." (p.75.)
These four things lead Nelson to pose the question, "...if I can sprout new limbs from my body-can I trust the seemingly reality of an out-of-body experience?" (p.76.)
Nelson points out that there are also people who are convinced that they are dead - they do not exist - Cotard's syndrome. "Cotard's syndrome patients think they are dead and that their bodies are decomposing or they are walking around in an afterworld." (p.88.)
These type of experiences led Nelson to remind us that "The brain is perfectly capable of creating experiences that are utterly convincing and are often described as "realer than real." (p.89.)
Nelson then takes a look at the elements which make up an NDE, from a neurological perspective. He points out the work of Dr Thomas Lempert of Berlin, who in the 1990's experimented on healthy subjects by causing them to safely faint in a laboratory. He found that sixty per cent of fainters had visual hallucinations; on the borderland of consciousness and unconsciousness. 10 per cent had an OBE. Comparing these to elements of NDEs, he found "...no real difference between the two types of experience." (p.125.)
The tunnel mystery solved:
Research by Dr Edward Lambert, a neurophysiologist, on pilots, found that "...when exposed to a force designed to bring on fainting, the pilot's peripheral vision began to dim...the pilot could only see within a small circle in front of him" -it was like looking through a tunnel. (p.129.) "When not enough blood is pumped to the head, the eyes fail first, causing tunnel vision..." (p.130.)
Out of body experiences in NDEs:
"Neurologists have discovered that out-of-body perspectives are created by disrupting how the brain puts sensations together to form the self's body schemas..." (p.139.)
"...out-of-body experiences are about a displacement or misapprehension oft he location of the whole body." (p.140.) The brain brings together various bits of sensory information from such places as the eyes and the vestibular organs in the ear. In an OBE these sensations get disconnected at the tempoparietal junction in the brain.
Nelson proposes that during an OBE in an NDE, "Consciousness has lost its bearings in relation to bodily position, touch, gravity and motion." (p.142.)
Presence of others during an NDE:
NDErs often report seeing a person or supernatural being during the experience. Nelson cites the work of Blank et al who "...discovered shadowy presences lurking in the tempoparietal junction..." of a patient. Instead of an OBE she reported (p.148.) a person behind her when her tempoparietal junction was electrically stimulated.
The Locus Coeruleus:
"Through its connections the locus coeruleus plays crucial roles in arousal and conscious states, paying attention and responding to stress." (p.156.)
Nelson suggests that when in danger " this experiment suggests that we perceive time slowing or our thoughts speeding when we're in danger." (p.171.)
"If we accept that the brain participates in spiritual experience then the orbital prefrontal must be responsible for giving us a glimpse of the rewards that will be ours when we go to heaven or reach enlightenment." (p.180.)
Summary to here:
"Low blood flow reaching the brain from fainting or cardiac arrest leads to many features of near-death experiences. If the tempoparietal portion of the brain shuts down, we have an out-of-body experience or have "sensed presences." When blood flow is cut off to the eye as well as the brain, we experience tunnel vision." (p.183.)
"During REM sleep, spinal paralysis sets in so we cannot act out our dreams...Our eyes and breathing muscles are left unaffected..." (p.188.)
During REM sleep the dorso-lateral prefrontal cortex is turned off. This area of the brain processes logical problem-solving and planning. It organises information, thought and emotions.
If in REM sleep the dorso-lateral brain were switched on, then we would get lucid dreaming. In lucid dreaming, we become aware we are dreaming whereas normally we do not realise we are dreaming when we dream, only when we awaken. "Lucid dreaming mixes the two conscious states of REM sleep and wakefulness but only in 3 percent of dreams do people enter the borderland of consciousness." (p.190.)
"The experienced lucid dreamer can feel a wide range of emotions, including fear, spiritual ecstasy and sexual bliss." (p.191.)
"Since lucid dreaming can be learned, turning on the dorso-lateral brain seems to be at least somewhat under our control." (p.194.)
"Recently, sophisticated brain-wave recordings have shown that lucid dreaming is a conscious state between REM and waking." (p.194.)
"A switch in the brainstem tilts us between these two states." Awake and REM sleep. (p.197.)
"...tucked away near the centre of the brainstem is a portion of the REM switch called the V1Pag. When it activates consciousness tilts towards waking and away from REM." (p198.)
Nelson located 55 people who had had NDEs. He asked them "...if during the transition (between wakefulness and sleep they had ever experienced visions, sounds, or paralysis, in other words REM consciousness." (p.200.)
"What we found was that the brain switch linking waking and REM consciousness was different in people who had had a near-death experience. Instead of passing directly between the REM state and wakefulness, the brain switch in these people was two-and-one half times more likely to blend the two states." (p.202.)
"Our study strongly showed that people who have had a near-death experience possess an arousal system predisposed to blending REM and waking consciousness." (p.202.)
The vagus nerve:
"Eighty per cent of the vagus conveys information to the brainstem." (p.206.) "Could wild vagus activity alone tilt someone into REM consciousness?" It seems so. (p.208.)
"When the vagus nerve is stimulated for medical purposes in patients, REM appears rapidly with sleep onset and REM intrudes into non-REM states." (p.206.)
"What is clear is that through its nerves the heart can cause REM consciousness in waking times." (p.207.)
The unearthly light:
"Light at the end of the tunnel can come from two sources. The first is ambient light that comes through our eyelids...A second source of light might, of course, be the light of REM consciousness...Light is the core business of the REM system, creating the visual images ..." (pp212-213.)
"Regardless of what gaps remain in our knowledge, experiencing the bliss of heaven while on earth must have its Genesis somewhere in the brain's reward system." (p.214.)
"...near-death experiences...are more akin to the lucid dream...Part of the dreaming brain erupts in a brain already awake...blending REM with waking consciousness creates experiences that are realistic and memorable." (p.214.)
Summary to here:
Nelson proposes the following near-death experience elements have the following physiological causes:
Tunnel - Low blood flow to the eye's retina
Light - Ambient light and REM visual excitation.
Appearing "dead" - REM paralysis.
Out-of-body - Tempoparietal REM deactivation.
Life review - memories from flight or fight.
Bliss - Reward system.
Narrative quality - REM dreaming and the limbic system.
"A sizable 42 percent of our research subjects felt "united, one with the world" during their near-death experience." (p.221.)
How does this occur?
"It seems possible that shutting down the tempoparietal brain could contribute to the loss of self in a mystical experience." (p.232.)
This was a deeply engrossing book to read. I have come across numerous explanations for the different elements of an NDE before, but this is a unified hypothesis that covers all elements.
I see relevance to the out-of-body experience, as I have covered in previous posts on this blog about scientific OBE research.
I now need to ponder the possible relevance of some of this material to UFO abduction accounts, for there seems some highly relevant material here. There is the 'oz factor", the loss of everyday activity which overcomes some abductees. Jenny Randles in the UK has written extensively on the 'oz factor.' Some abductions invlove a "floating sensation." Many abductions are reported to have occurred on the borderland between sleep and awake. There is also the bodily paralysis which overcomes many abductees.
What do blog readers think of Nelson's work?