Sep 4, 2009

The Necessity of A Physical Brain For the Existence of Consciousness

I admit to being in a somewhat mischevious mood. Then again, my blog has always been thought-provoking. :D
ST Sep 3, 2009
Devotees pray for the dead
By Yen Feng

WHETHER it was the sight of more than 5,000 altars filling the great hall or the memory of a dear family member, no one could be sure.

But it was enough to draw tears from the thousands of devotees who bowed their heads in prayer at the Kong Meng San Phor Kark See Monastery, off Sin Ming Avenue, on Thursday.

From noon to 9pm, Buddhists took part in Ullambana, the annual traditional custom of praying for departed family members on the 15th day of the seventh lunar month.

Temple staff said more than 5,000 requests had been put in this year by devotees to set up the temporary altars. It took volunteers three days to complete the spectacular ceremonial hall, filled with rows of identical tables brimming with sweet offerings.
Praying to the dead provides consolation for the living. Apart from that, the prayers serve no purpose. After all, the dead are already ... dead. Right?

Well, let us take a few moments to seriously examine this matter. Why might we believe that death is the end of our brief existence? Probably because we think that consciousness is dependent on the physical brain. If the brain has failed and begun to rot away, then that's presumably the end of the story.

But wait. What if the existence of consciousness is not dependent on the brain?

One good starting point for analysis may be the near-death experience. They used to be rare, but interestingly, are said to have become much more common ever since the development of modern cardiac resuscitation methods.

NDEs are a certain range of experiences that some people report having, at the time when they were clinically dead or otherwise very close to death. (Of course, they only report these experiences after they've been successfully saved, for example, by doctors in the emergency ward). What is an NDE like? Here's an excerpt from Wikipedia:

The traits of a classical NDE are as follows:

- The notice of a very unpleasant sound or noise.
- A sense/awareness of being dead.
- A sense of peace, well-being and painlessness. Positive emotions. A feeling of being removed from the world.
- An out-of-body experience. A perception of one’s body from an outside position. Sometimes observing doctors and nurses performing medical resuscitation
- A "tunnel experience". A sense of moving up, or through, a passageway or staircase.
- A rapid movement toward and/or sudden immersion in a powerful light. Communication with the light.
- An intense feeling of unconditional love.
- Encountering "Beings of Light", "Beings dressed in white", or other spiritual beings. Also, the possibility of being reunited with deceased loved ones
- Being given a life review.
- Being presented with knowledge about one's life and the nature of the Universe.
- A decision by oneself or others to return to one’s body, often accompanied by a reluctance to return.
- Approaching a border.

In the more dramatic NDE cases, the person even reports floating out of his body, and being able to observe, in very specific terms, what was happening at the accident scene/hospital ward; his account is then later verified by other eyewitnesses.

Although NDEs are uncommon, they are common enough for some of their characteristics to have crept into our everyday language. For example, you have probably come across phrases such as "the light at the end of the tunnel" or "I saw my whole life flash before my eyes". These are literal descriptions of some characteristics of NDEs.

The most obvious challenge to NDEs is, of course, that they are hallucinations, nothing more than the crazy, addled perceptions of a person whose brain is all mucked-up, because he was already dying.

But let me offer an excerpt of a counter-argument by a researcher on the topic. Dr Peter Fenwick is, among other things, Consultant Neuropsychiatrist emeritus at the Maudsley Hospital in the UK; Senior Lecturer at the Institute of Psychiatry; and Consultant Neuropsychiatrist at the Radcliffe Infirmary Oxford; and Honorary Consultant Clinical Neurophysiologist at Broadmoor Hospital. Here's Fenwick, in his own words:

"So, now we come to the really important question: what happens when an NDE
occurs during a cardiac arrest, and why is this important?

The first point is that signs of cardiac arrest are the same as clinical death. There is no detectable cardiac output, no respiratory effort, and brainstem reflexes are absent. If you are in this state and I put a tube down your throat, you will not cough. You will have dilated pupils. Your blood pressure has fallen to zero. You are, in fact, clinically dead. Even if I start cardiopulmonary resuscitation (CPR), I cannot get your blood pressure any higher than 30 millimetres of mercury, and this is not going to produce an adequate blood flow to your brain.

A number of studies show that the longer CPR is continued, the more brain damage occurs. So it is not an ideal intervention. We know that after a cardiac arrest, both NDErs and non-NDErs suffer brain damage, but we do not know whether the amount of brain damage in the two groups is the same or different. During CPR, you are not going to be able to perfuse – that is, force an adequate amount of blood through – the brain. When the heart does finally start, the blood pressure rises, and there is a slow resumption of circulation and lots of technical reasons why your brain function does not return instantly. And the point to remember is that your mental state during recovery is confusional.

What should be clear to you now is that it is not a good thing to have a heart attack. In their 1999 study of cardiac arrest and brain damage, Graham Nichol and his colleagues found that out of 1,748 cardiac arrests patients, only 126 survived (Nichol, Stiell, Hebert, Wells, Vandemheen, and Laupacis, 1999). Most units range between 2 and 20 percent resuscitation rates. Eighty-six of Nichol’s survivors were interviewed, and most of the people who were resuscitated had evidence of brain damage.

Simultaneous recording of heart rate and brain output show that within 11 seconds of the heart stopping, the brainwaves go flat. Now, if you read the literature on this, some sceptical people claim that in this state there is still brain activity, but, in fact, the data are against this in both animals and humans. The brain is not functioning, and you are not going to get your electrical activity back again until the heart restarts.

The flat electroencephalogram (EEG), indicating no brain activity during cardiac arrest, and the high incidence of brain damage afterwards both point to the conclusion that the unconsciousness in cardiac arrest is total. You cannot argue that there are ‘‘bits’’ of the brain that are functioning; there are not. There is a confusional onset and offset, and there is no brain-based memory functioning. Everything that constructs our world for us is, in fact, ‘‘down.’’ There is no possibility of the brain creating any images. Memory is not functioning during this time, so it should be impossible to have clearly structured and lucid experiences, and because of brain damage, memory should be significantly impaired, and you should not be able to remember any experiences which occurred during that time."
In layman's terms, what is Fenwick saying? Firstly, he referrs to NDE cases involving cardiac arrest patients. In these cases, the brain completely stops working and there should be no way that it can enable the patient to continue experiencing anything. Even if the patient does have any experience, he should not be able to remember it and report it later. That's because his memory has already stopped functioning. After all, the person's brain has shut down completely.

The fact however is that cardiac arrest patients can and do have NDEs. During these NDEs, they hear, see, move, feel and think (or distinctly perceive themselves doing so). They may even perceive themselves as having conversations with "Beings of Light"or long-deceased relatives. All of these perceptions indicate that the patient's consciousness is still operating very actively. Furthermore the patient is later able to remember his experience om detail, and can give a clear, lucid account of it. This indicates that his memory was still functioning at the time when his brain had shut down.

What does this suggest?

That ... consciousness can exist without a physical brain.


Anonymous said...

Mr Wang,

I beg to differ on this issue. While the brain might be clinically dead during NDE, it does not suggest that consciousness therefore exist outside the brain. As far as research goes, no one has yet been able to pinpoint consciousness. As such till today, debates are ongoing as to whether consciousness is a collection of activities, or is there a specific location where we can locate the "seat of consciousness".

The brain has been known to fabricate memories, this is especially so when a traumatic event has occurred. And as you rightly say that almost all patients with cardiac arrest have some form of brain damage, we cannot rule that such "recollection of NDE" can stem from the brain damage. People who have gone through PTSD also have memories that seems very lurid, but are often times not accurate.

This is also why forensic psychologists try to not place too much weight on eyewitness accounts, as memories is a very tricky issue. Many classic studies (such as Terr, 1988 McAdams, 1993, Loftus, 2002, 2003; Schacter, 1996, 2001) shows this, and even suggests that false memories are easy to create, and supposedly traumatic events are recalled filled with inaccurate details.

Indeed Culter & Pernod (1995) estimates between 2000 to 1000 people are wrongfully convicted each year in US due to faulty eyewitness testimony.

As such I suggest that we do not place too much weight on memory of a NDE to suggest that the consciousness exist outside the brain. It could be just as much that the memories of the event have been recreated thereafter.


Anonymous said...

the next question to ask is: If consciousness can exist without a functioning physical brain, how long can it last?

Indiana said...

Or that Fenwick is wrong, and during that time there are still minute impulses occurring in the brain but that we do not have a machine capable of reading them.


Perhaps the reports of "seeing something" are in fact brain damage, they are the reconnection of electrical activity in the brain cross wired across damage and the damage is being reported as the noise and the light.

Just some counter thoughts.

Mr Wang Says So said...

Dear Scott:

I understand your point about the debatability of consciousness having a location.

My post however is not so much about the location of consciousness, but about whether it can exist without a brain (never mind "where" the consciousness is).

As for your next point, Fenwick has elsewhere drawn a distinction between hallucinations and NDEs. There are important qualitiative differences between the two - one of them is that hallucinations can literally be about anything, while NDEs, across an entire spectrum of patients, tend to have a definite list of characteristics (see list in my main post).

People definitely can have "false memories". The key point is that Fenwick is saying that when the brain has stopped so completely, there cannot be any memories (false or otherwise). Hallucinations should not even be possible.

Anonymous said...


IMHO, the trilogy summarises the premise of consciousness. This philosophy discussion has been going on for quite a while.

Neo presence in the matrix, where the body is sleeping, but he is conscious and @ the end where the body (ie brain) dies but his conscious lives on in the matrix...

So can we be conscious without the body? Can we "upload" our memories into a computer to give it consciousness?

What consitute consciousness???


Rick said...

Mr Wang,

A patient's brain might invent false memories after it has resumed functioning, and attribute those memories as having occurred during his coma.

The only way to prove that the patient did experience an NDE is where the patient can describe something that happened in the operation room during the period of time where his brainwaves were flat. Something that was impossible for him to know without having seen/heard it.

Anonymous said...

Please do not give the Pappies any ideas!
They might use A*STAR to research on how to download Ah Kong's brain into a PC.
Then really LKY FTW FOREVER!

Anonymous said...

Mr Wang,

You reply quick!

I do see where you're coming from as well, I think what I was trying to say was that, while the brain might have been clinically dead, but when it revives and becomes functioning again, there is nothing to stop the brain from creating false memories of the event. Therefore memories of NDE, not as much as memories that lie outside the brain, but recreated memory of the event is a big possibility as well.

In this case, what Fenwick says does not necessarily support the hypothesis that the consciousness can reside outside the brain.

Hope that clarifies my position on this.


Anonymous said...

Hmm, if consciousness can exist without a physical brain... then does it age and loses its functions like the physical body?

If an old man suffering from dementia dies, would his consciousness remain at the same state?

Anonymous said...

This brings to mind the classic anime movie Ghost In The Shell.

Mr Wang Says So said...

Hello Rick & Scott:

Yes that is a possibility.

Some NDErs have reported that they floated out of their bodies and were able to observe events at the accident scene / hospital ward. Their accounts were then verified & confirmed by the people who were present there.

However, so far none of these have occurred under experimental conditions.

But aha, such an experiment is indeed currently underway, at the Morriston Hospital in the UK.

The method is to place distinctive, usual pictures in the emergency ward, at angles that are not easily noticeable in the course of daily activity, but would be noticeable if indeed a patient (or his consciousness) could float outside and above his body.

If an unconscious patient later survives, and reports later that he had an NDE, and is able to say: "Oh, I even saw a strange picture on a very high shelf in the ward, very close to the ceiling. It was a picture of [ ] and it looked like [ ]."

... then that is proof that his experience was not a false memory.

Mr Wang Says So said...

Typo, should be "unusual pictures".

Anonymous said...

We used to think the Sun runs around the Earth.

We are saying the brain is the center of everything.

Chee Wai Lee said...

The weakness in the argument lies with, as some other readers have pointed out, the dimension of time.

Saying "I experienced these things *after* I became brain-dead." means nothing unless the experiences can be recorded or measured by the external environment. And these measurements need to be repeatable. How many times have we had dreams which seem (to us) to last a longer time (or a shorter time) than we were actually asleep?

Chee Wai Lee said...

A better experiment is for a container holding a previously unknown item to be open *after* clinical brain-death and closed again *before* revival. Requiring visual identification would help make this more water-tight, particularly if the subject is blindfolded for the experiment.

If the item is identified, then the person was able to observe the event after brain-death as an external conscious entity.

Frankly, that sounds like a damn dangerous experiment unless there are ways to cause brain-"death" followed by reliable ways for revival without ill effects.

Mr Wang Says So said...

There are many NDE accounts along the following lines:

(Excerpt from Wikipedia)

Many NDE-accounts seem to include elements which, according to several theorists, can only be explained by an out-of-body consciousness.

For example, in one account, a woman accurately described a surgical instrument she had not seen previously, as well as a conversation that occurred while she was under general anesthesia.

In another account, from a prospective Dutch NDE study, a nurse removed the dentures of an unconscious heart attack victim, and was asked by him after his recovery to return them.

It might be difficult to explain in conventional terms how an unconscious patient could later have recognized the nurse.

Mr Wang Says So said...

Chee Wai:

It's not that any person will be deliberately brought close to death for the sake of this experiment!

It is simply that the unusual pictures (or objects, in your proposal) will be strategically placed in emergency wards.

Unconscious patients (eg who've just had a traffic accident, heart attack etc) will be brought in and treated as usual.

Over time, out of a large pool of patients (eg 500), one or two patients will inevitably report an NDE. When that happens, the researchers can ask him what he saw. If he accurately states that he saw Unusual Picture A or Unusual Object B, then we have evidence that indeed this was not a false memory.

Anonymous said...

I happened to experience this before. That was in 1984 or 1985; I just came back from my camping after “O” level exam. Tired and sunburn, I took a cold shower and went to sleep with fan blowing directly to me at high speed.

I believed my body temperature drop too fast, I was very lucky that my grandma came into my room and woke me up. My body was very cold and I just can’t stop shaking

It was like having a dream - I was in a very dark tunnel walking towards the end which was very bright, as I was walking towards the bright light, I saw my family calling out to me – “come back, don’t go”. All the things I did in me past kept coming into my mind, repeating again and again and I continue to walk towards the light until my grandma woke me up.

It was an experience that I will never forget and without my grandma I may not be here writing this.
Your blog on 26 Aug reminded me of my grandma again; just like you, I was very closed to my grandma.

Chrisloup said...

information must be stored somewhere. unless you are proposing that information can be stored in the aether. (wow, unlimited harddisk space then) (where are memories stored?), then it would be hard pressed to argue that a physical brain is not a necessity.

since brain damage, dementia, lobotomies etc indicate that damage to the brain damages memories.

even behaviour can be changed by damage to the brain, (eg: someone can become a sex addict..)

I believe the brain is the mind is soul. ie: we are just moist robots under the delusion we have free will.

Anonymous said...

Christians cannot deny that consciousness can exist without a physical brain.

Unless, of course, they believe that God has a physical brain and it's stored safely in some corner of the universe.

Actually by extension, the argument applies to Satan, ghosts etc.

Anonymous said...

"If you believe, proof is not necessary. If you do not believe, proof is not possible"

Quote by David Rossi, Criminal Minds

Anonymous said...

Dear Chrisloup

As a analogy, Asus is offering online storage.

Perhaps, the brain is the ROM\BIOS\OS\RAM?

Anonymous said...

Where's angry doc?

PS: God could be cloud computing?

Ah Wang

Anon said...

I think this sort of discussion is healthy, as long as people realise that it's highly speculative and full of conjectures.

Please don't believe for a moment that this is "evidence".

Scott in the first comment got it spot on.

Anonymous said...

When my dad was in the ICU and unconscious, he was put in a room that was extremely cold with the air-con blasting away. The nurse claimed that the air-con had malfunction and other rooms were not available. She claimed that my dad is unconscious he will not feel the cold. An argument ensued and we requested for extra blankets for him as he was visibly shivering and for the maintenance crew to repair the air-con immediately. When he was awoken, he told me that he can hear the discussion with the nurse but he cannot response at all. Furthermore he did felt very uncomfortable and cold. Hence it is very doubtful if an unconscious person is really unable to feel discomfort or unaware of their surrounding just because they cannot response to stimulus. As I understand, some Buddhist recommend that the dead be allowed to rest for at least 24 hours before their body are touch because it can be very sensitive and painful if their stiffen body are forced into movement. Also the dead is likely to be conscious even if their heart had stopped for an hour or more.
Some insights to a brain function being shut down can be found at this url:

Chrisloup said...

Yeap. if you can erase memories, it means its on the brain, ergo, either the brain was recording during the NDE and instructments are not sensitive enough, OR the brain is recreating such memories, without a double/triple blind experiment, some of these experiences can be down to sheer coincidence or 'sporadic eidetic memory'

there is a term for a phenomenon, that is described for past life experiences, where the memories from such actually come from things a person might have seen just casually , yet is noted in the subconscious and later recalled as part of a past life experience..which I can't remember off hand.

Anonymous said...

Anon 4:58

Very true.
Until u have a near death experience or an eerie "out of body" experience.

*meandering off topic due to inability to meditate \ misplacing medication*

Then you might even (against all reason or logic) join the flat earth society (aka religious right) like I did.

Then again, it should be obvious that reason or logic is not my forte.

PS: Can't wait for next installment ... slow day at the office ...

Ah Wang

angry doc said...

"Where's angry doc?"

Truth be told angry doc was busy working on something that could one day affect the lives of all of us...

Besides, others have posted on alternative explanations for the NDE, right from the first post too.

There is currently no conclusive evidence that consciousness can exist outside a physical body - some accounts of NDE and reincarnation are admittedly rather convincing, but even then these accounts are given by people with physical bodies - what we are accessing is '*memory*, not *consciousness*.

(Consciousness, curiously, is its own proof - we cannot say if someone is conscious of something; only he himself can...)

Something like a ghost would be a more convincing evidence, but that's another thing altogether.

To me the fact that we have physical bodies is a good reason to believe that consciousness is a product of the physical body - if our consciousness could see the hidden picture on top of a high shelf in the resuscitation room, why bother evolving eyes?

If we can think without a brain, why bother developing one?

Seems an awful waste to me...

From a moral point of view (not that angry doc is a moral person, mind you) a belief in a consciousness that survives death can be a bad thing; it can lead to people accepting that bad things happen to people because of their past karma, or that it's OK to "shoot them all and let God sort it out".

Ape said...

Just to throw in something for thought...

Most people are comfortable with the notion that memory resides in the brain. (And the brain does the processing as well).

What if memory is not stored in the brain? What if the brain is merely a "processor"? If the processor is not working, our sensory organs somehow sends all the signals directly to whatever "storage" place is, bypassing the brain?

Ape recalled a documentary where it was mentioned that someone believe memory is actually stored all over our body and the evidence used to support his claim are organ transplant patient who somehow developed certain behavior similar to the donor after the transplant. Pardon ape for not able to recall who is the researcher.... ape's brain still primitive :p

Cappella said...

Hmmm, this finding is known within the Buddhist world, where consciousness is separated from the body during death. Through meditation, it is possible to do it, though it requires a very skilled person to do so. After all, consciousness is an energy which can be transformed from a state to another. There is a lot of Buddhism doctrines on the relation of consciousness and the material body, and how they function together. One can Google all about it.

Anonymous said...

My friend's father passed away about 6 months ago. They left the body untouched for 24 hours in accordance to their Buddhist beliefs. I only thought it was weird.

But they explained to me, that the Buddhists believed that the "soul" or "essence" of the person will slowly travel out of his body on death. The "soul" will gather itself and exit through the head.

AFter 24 hours of chanting, the entire body was cold. But the top of the head, was warm. They did not burn incense, etc.

Chee Wai Lee said...

Mr. Wang,

That makes more sense. I would feel more comfortable with the experiment if they only changed the environment after brain-death is encountered. That way, we can reduce the possibility of error.

I wonder how much of this is related to cases where coma patients were able to sense everything around them but unable to react. Must have been harrowing to hear your family discuss whether to turn off your life-support and not be able to say "no".

Mr Wang Says So said...

It's not related. I've been under GA before; I had that kind of experience of being able to hear what people were saying, and not being able to respond.

NDEs are not quite like that. If you read NDE accounts, in the person's own words, you will see what I mean. (You can look around the Internet for such accounts).

One of the common characteristics is that the person feels unconditional love. He feels completely safe, completely loved, by a divine presence often represented by the white light. He feels so completely loved that it is with great reluctance that he eventually returns to his own body.

Such experiences are reported by people from all cultural backgrounds, including atheists and very young children (who have not heard or been taught about "God" in any form).

Anonymous said...

So the summary of the articles goes like this:

Say Ah Wang meets Miss X.
They have a long courtship ...


Ah Wang believes in true love and should marry.
Ah Wang's friend, Ah Tan thinks there is no such thing and marriage is obsolete\wrong.

Apparently, they are both wrong...

(Illusion of Free Will)
Ah Wang makes Miss X ... Mrs Wang.
Ah Wang thinks he made the decision freely but turns out that it is a myth. Actually, he did not do it out of free will.

As proof, when the office SYT (with D cup) gives Ah Wang "half ball", little Wang is at attention 10s before Ah Wang even realises that he is staring at a longkang.


Yet apparently there is such a thing call "consciousness". Ah Wang is conscious that if he does anything funny, he will experience a NDE (I use the term loosely) courtesy of Mrs Wang. So while the brain says "Go for it", Ah Wang is able meditate on the vision of kneeling on durian husks to clarify his thoughts. His consciousness keeps his brain in control. He also remembers Ah Tan had been so close to his death courtesy of the ex Mrs Tan until he seen his own dead body until he returned reluctantly as a undead as he still has to pay alimony.

Therefore, the brain is not necessary for consciousness.

But Angry doc does not believe so. Cos if there is no need for a brain(or eyes) then why bother evolving them? And ape thinks that like Ah Wang, little Wang have the ability to remember too.

My comprehension got pass or not?

Ah Wang

Anonymous said...

I recall reading somewhere that a human head that is decapitated is still conscious of its surrounding for about a minute or so.

Perhaps the brain still has some temporary function(s) that is(are) not measurable or detectable with our current state of technology?

angry doc said...

I think we need to see consciousness in the context of what we know about evolutionary neurobiolgy.

From my reading, I tend to favour the interpretation that consciousness is an emergent phenomenon - that is to say consciousness 'evolved' as a way for the brain to organise sensory information. The brain acts, then fools the consciousness into thinking that the consciousness did.

The problem comes because the illusion is too perfect - we begin to think that we have free will and began to construct our moral and legal system around the concept of free will. Libet's experiments should have overturned all that, but the world at large ignores it, or exists in a congnitive dissonance, because the illusion of free will continues to be real (just like how steak continues to taste good even after you realised it's all in the Matrix), and because our moral and legal system seem to have fucntioned so well despite their flawed basis.

Anonymous said...

Is angry doc Buddhist?

While the 3 blind man may each have a different perception of reality (elephant) ... kill an elephant and it stays dead ... even for the 3 blind man.

So how should we construct our legal system differently?

Libet's experiments are hardly perfect ... yet. Besides it does not disprove that whether it is the brain or a higher conscious that makes a decision ... we (the entity) still respond to external stimuli\incentives\KPIs.

Ah Wang

*sudden vision of angry doc n Mr Wang side-by-side comtemplating the meaning of life ... while maintaining the tree pose yoga stance and chanting the diamond sutra*

Anonymous said...

Wang, "unconditional love" is also described in Buddhism, and the Chinese "MO" and "RU" schools of thinking.

Why do you link only to "GOD"?

Anonymous said...

I believe the Mao Taoist have described rituals on how to "leave your body".

Anonymous said...

Mr Wang,

The brain is just like any other organ with its specific function.When the brain is dead, is possible that the heart is still pumping .Therefore consciousness reside in the heart.

bluB said...

Dear Mr Wang,

That was a good read.

You have analyzed consciousness from a NDE perspective. However, if one seeks the beginning of consciousness, when does it begin?

A minute-old child, a year-old child. Do they have consciousness? I probably became aware of my own existence only when I was 4 or 5? I can't pinpoint the exact moment. Can anybody?

Perhaps then the focus ought not be on consciousness but the soul? I reckon ensoulment begins at conception. Or at the very earliest, at birth. It appears to occur before consciousness arises.

Similarly, in a NDE, are the soul and consciousness mutually exclusive concepts?

And consciousness. They can be switched off? When I sleep. When a person goes into a state of automatism?

so why does it matter that consciousness can exist without the brain?

i think the fundamental question ought to be, is there a soul? if so, what is it?

pardon the lack of structure. these are just thoughts that i occasionally think about, which i believe is more of my sub-conscious (can there really be such a concept?) mind at work.

Chen said...

If we are talking about the existence of conscious without a physical brain, then we are wading into deep murky philosophical waters.

There is an interesting debate between philosophers on whether the physical world exist. (Yeah, crazy philosophers, but they have an interesting point) Basically, all our knowledge of the physical world is gained through our senses. It is possible that an all powerful evil being is feeding our conscious false sense data so that we erroneously believe that a physical world exist. Sort of like being in the matrix, but worst.

The philosophers don't like this uncertainty, and they try to find a way out. René Descartes came up with something brilliant: "I think, therefore I am" as he stated famously, deducing that the existence of a thinking entity is something we can definitely be sure of. From this premise he start making other deductions that unfortunately I feel are not that convincing.

Anyway, as far as I know, we are still stucked at this stage. We know that our own conscious thinking mind exist but we can't be absolutely sure of anything else, not even the existence of other conscious thinking minds. So... theoretically it is possible that NDE is real, we can see without our eyes, hear without our ears, perceive the physical world without being part of it or the physical world is just an illusion.

Personally, I would prefer to use occom's razer and assume that those patients are just having hallucinations.

Pete of Perth said...

We are but worm food...

Anonymous said...

There seems to be some confusion over NDE and unconsciousness. Probably the reason why there is so much debate over the definition of clinical death.

IIRC, NDE implies that there is no sign of life, no pulse, no breathing, no brain waves. In most forms of unconsciousness, there will be some kind of body function operating, usually a beating heart.

A person in a coma is unconscious (i.e. he/she cannot be woken up) but that does not mean the person is having an NDE and he/she may still be sensing environmental stimuli even though he/she cannot respond to these stimuli.

This is why it is a contentious issue on when to turn off the life support systems of an unconscious person. However, to me, if the person cannot maintain esential body functions (e.g. breathing or heart-beating) plus the complete absence of brain activity without the use of machines, the person can be considered as dead. This view may change when technology has advanced to the stage to be able to put humans into deep-freeze without damaging their bodies permanently.

Anonymous said...

2009 - 10 - 06

cancer or heart attacks.

Moments before death, the patients experienced a burst in brain wave activity, with the spikes occurring at the same time before death and at comparable intensity and duration.

Writing in the October issue of the Journal of Palliative Medicine, the doctors theorize that the brain surges may be tied to widely reported near-death experiences which typically involve spiritual or religious attributes.

Mr Wang Says So said...

Well, that raises the possibility that spiritual experiences (if they exist) can have physiological markers.

Then again, that possibility in itself is nothing new. The story of the resurrection of Jesus, if true, must necessarily have plenty of physiological markers.

Anonymous said...

There is a good documentary on this subject by the BBC called The Day I Died. I gave it a 5 star rating.

Check it out. You won't be disappointed.