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Near Death Experiences & Brainstem Cardiac Arrest and Pim van Lommel
A book explaining the biology of NDEs
Read Chapter 3 for an explanation of the "light experience" and seeing auras of light
The necessity for atheism proven by the Bible and Koran
Followers of Islam doomed by the Sunnah
Click hier om een recensie van "Eindeloos Bewustzijn" te lezen
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To the left is an old engraving illustrating a deathbed light experience. An unfortunate young woman receives the solace offered by her religion during her last moments. And during these last conscious moments, she perceives herself to be illuminated by a heavenly light, as well as the all-seeing eye of her God, and realises she will go to the paradise promised to all believers. The watching priest and nun quite evidently do not see this light, just the expression of joy on the dying woman's face. This is true of all deathbed experiences. Dying people say to others clustered around their beds that they can see a "wonderful bright light that does not hurt their eyes", but no-one else other than the dying people can see this light. The same is also true of those observing people who later report having undergone near death experiences at the same time as observers were watching them. The observers never report seeing the light, or the other experiences undergone by those who underwent these near death experiences. Such experiences of light and passages through tunnels are profoundly moving experiences to those who undergo them. Even so, these experiences are explained by the functioning of the body during these experiences. I recently wrote an article published in the Skeptical Inquirer describing the changes in body function causing these experiences, but I soon found this article, while very adequate, still did not clearly demonstrate to some people exactly how such experiences could arise, nor was it entirely complete. So this webpage is intended to supplement this article (also see chapter 17, reference 8). Body function and seeing light As a practical physician, my initial approach is always anatomical - first see what apparatus is available to perceive light. Light which everyone sees with their eyes as well as photgraph is electromagnetic radiation in the wavelength range 400 to 700 nanometers (one nanometer is 0.000,000,001 meter). The sequence, or rather the chain of perception and seeing light is as follows. 
Failure of any link in this chain of perception means affected persons are blind and will see nothing, no light, only darkness. Furthermore this chain of perception reveals how it is possible for the body to generate light and tunnel experiences, so that people can perceive bright light, or experience darkness, or pass through a tunnel to enter a region of bright light, while observers notice none of these things. Pupils & light The pupils regulate the amount of light entering the eyes by narrowing to admit less light, and by widening to admit more light. Pupil diameter in the normal human eye can vary from as little as 1 millimeter to as much as 10 millimeters. The area of the pupil through which light can enter the eye is a circle, which means that when ambient light levels remain constant, the pupil can admit as much as 100 times more light when widening from 1 to 10 millimeters in diameter (see drawing below).  So a person whose pupils widen significantly will notice that their surroundings become lighter, while those in the vicinity of that person, and whose pupils do not widen will notice nothing. And when that person says, "Everyhting is getting brighter and brighter", or "I can see a bright light that doesn't hurt my eyes!" - these other people will say that the person who sees the bright light is hallucinating, even though that person really does see a bright light that does not hurt their eyes. Simulating "seeing the light" I simulated this situation with the two garden photographs shown below. The first photograph is normally exposed and the garden is seen normally. Then I widened the diaphragm of the camera without changing the exposure time. This is the same situation as happens when the pupils suddenly widen in a situation of unchanged ambient lighting. The result was that the garden appeared flooded with bright light, and some parts of the image were out of focus. This is a wonderful demonstration of the role of the pupils in generating the perception of "bright light".
But why should the pupils of a person widen at a time when the pupils of other people in their vicinity do not widen? Pupils will widen as a result of serious oxygen deficiency, as a result of surprise or fear ("eyes like saucers"), as a result of increased sympathetic nervous system activity such as occurs during many severe illnesses, and as a result of drugs such as adrenaline. One or more of these things may occur in a dying person, or as a result of injuries, accidents, life-threatening events, and fear. Any one, or more of these factors is always present in someone who believes their lives to be threatened, to be near to death, or actually dying. I will give an example. A woman dying in the Mothers' Hospital In the article in the Skeptical Inquirer, I used the example of a report of the experiences of an unfortunate woman who during 1923 AD lay dying of heart failure after a difficult childbirth in the Mothers' Hospital in Clapton, London, England. This report is published in the book by Sir William Barrett called "Death-Bed Visions. Psychical Experiences of the Dying" (1). It is a report which particularly appeals to me because it clearly illustrates the role of the pupils in the perception of "bright light". Furthermore, it also appeals to me because I once worked in this same hospital as an anesthesiology resident during 1978-1979. A photo of the hospital shows it as it was when I worked there, and it had not changed much since 1923 when the events in the report occurred (see photo below).  The Mothers' Hospital has since been demolished and replaced by a housing estate. But at the time I worked there, as well as during 1923, the district of Clapton was inhabited by the poor and socially deprived. And during 1923, it was not uncommon for young women to die during childbirth. Heart failure was a relatively common cause of death at that time, usually as a result of heart valve diseases caused by a disease called "rheumatic fever" which was common among poorer people in the earlier years of the twentieth century. The full report of this woman's passing reveals a touching affirmation of her religious beliefs, although the cause of her experience was rooted in her body function. Lady Florence Barrett was the wife of Sir William, and was also the obstetrician of this dying woman. She reported how the woman revivied after a short period of unconsciousness. Suddenly she looked eagerly to one part of the room, a radiant smile illuminating her whole countenance. "Oh, lovely, lovely," she said. I (Lady Barrett) asked, "What is lovely?" "What I see," she replied in low, intense tones. "What do you see?" "Lovely brightness - wonderful beings." It is difficult to describe the sense of reality conveyed by her intense absorption in the vision. Subsequently she had other visions among which a vision of a recently deceased sister. But then she turned to her husband, who had come in, and said, "You won't let the baby go to anyone who won't love him, will you?" Then she gently pushed him to one side, saying, "Let me see the lovely brightness." The matron was also present, and reported: Her husband was leaning over her and speaking to her, when pushing him aside she said, "Oh, don't hide it; it's so beautiful." These last two passages reveal that the presence of her husband before her eyes blocked her vision of the "lovely brightness", something which could only happen if the brightness was due to light entering her eyes. No-one else reported seeing a lovely brightness in the room.So the only way this woman could see a lovely brightness due to light entering her eyes under these circumstances was due to widening of her pupils! Widening of the pupils is one cause of "seeing the light", or of being "engulfed by light". Yet while widening of the pupils is a cause of this experience, it does not explain light experiences undergone by those whose eyes are closed, or those people who are in the dark. These light experiences are due to other causes. Visual cortex and light Nerve fibers from the eyes eventually end in the visual cortex, (number 5 in the drawing above). This part of the brain is highly structured, because the positions where the nerve fibers from the eyes terminate in the visual cortex are related to where they originate in the retina. Accordingly the visual cortex has a highly structured organisation. One consequence of this is seen in the effects of activation of the visual cortex due to factors such as:
All these effects can give rise to the visual experience of bright light, as well as the experience of passing through a tunnel to enter a region of bright light as was suggested by Dr. Susan Blackmore (5). So changes in eye and brain function can generate the sensations of light, of bright light, as well as sensations of passing through a tunnel to enter a region of light. Even so, this still does not explain all experiences of light. Hallucinations The effects of severe disease, the mental effects of drugs, the mental effects of withdrawal of some drugs, and well as the effects of some mental states can all induce states of mind during which people hallucinate that they see light, or experience light. It does not really matter that these people are hallucinating, because they really are experiencing light, or seeing a bright light. Indeed, functional brain scanning of hallucinating people reveals that the brain areas concerned with vision are just as active in these people as if they were seeing things with their eyes (6,7). Conclusions These are the mechanisms by which the functioning of the body can generate the experience of light, or of being embraced by the light during near death experiences. I am sure this discussion is incomplete, but it does reveal that the functioning of the mechanisms of the human body provides provable alternative explanations for these wondrous experiences free from the necessity to invoke unprovable spiritual or immateral explanations. References.
© G.M. Woerlee Last revised 1 July 2008
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Many people reporting near-death experiences tell of seeing a wonderful "bright light that does not hurt the eyes", "wonderful brightness". They may pass through darkness to "enter the light", or they pass through tunnels to enter the light. These are all part of the near death experiences undergone by some people.
Normal vision
Pupils wide open
