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Jason Braithwaite
#1
So anyone with a better grip on the functions of the brain have any opinion on Jason Braithwaite's references to EEG activity here: http://www.ukskeptics.com/the-dying-brain.php

“However, the emerging evidence is somewhat unhelpful for the survivalist. Tao, Ray, Hawes-Ebersole, and Ebersole (2005) compared EEG activity from surgically implanted electrodes placed in or around deep sub-cortical regions of epileptic patients, with cortical EEG electrodes placed on the scalp of the same patients. The results were quite surprising. Tao et al. showed that for 90% of cases, large amplitude paroxysmal firing needed to recruit 10 cm2 of brain tissue in order to show up against background cortical EEG traces. In other words, large seizure-based activity was being recorded by the surgically implanted electrodes (indexing clear and widespread brain-seizure activity) which was completely absent from scalp-based EEG traces until it propagated through and excited 10 cm2 of brain volume. This is a considerable amount of brain tissue.”

“Furthermore, a recent study that employed both EEG and brain-imaging (fMRI) techniques to explore seizure processes found significant increases in localised cortical neural activity (indicative of a seizure) in the fMRI BOLD (blood-oxygen-level dependant) response, which was completely absent from the EEG data (Kobayashi, Hawco, Grova, Dubeau, & Gotman, 2006). This is particularly striking in that this occurred despite the fact that the intense seizure activity occurred in a region where EEG electrodes were closely spaced. Kobayashi et al. note that this is striking as the EEG completely missed the most intensely discharging region despite the fact that this region was also located at the cortical level.”
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#2
(01-28-2018, 04:36 AM)Desperado Wrote: So anyone with a better grip on the functions of the brain have any opinion on Jason Braithwaite's references to EEG activity here: http://www.ukskeptics.com/the-dying-brain.php

“However, the emerging evidence is somewhat unhelpful for the survivalist. Tao, Ray, Hawes-Ebersole, and Ebersole (2005) compared EEG activity from surgically implanted electrodes placed in or around deep sub-cortical regions of epileptic patients, with cortical EEG electrodes placed on the scalp of the same patients. The results were quite surprising. Tao et al. showed that for 90% of cases, large amplitude paroxysmal firing needed to recruit 10 cm2 of brain tissue in order to show up against background cortical EEG traces. In other words, large seizure-based activity was being recorded by the surgically implanted electrodes (indexing clear and widespread brain-seizure activity) which was completely absent from scalp-based EEG traces until it propagated through and excited 10 cm2 of brain volume. This is a considerable amount of brain tissue.”

“Furthermore, a recent study that employed both EEG and brain-imaging (fMRI) techniques to explore seizure processes found significant increases in localised cortical neural activity (indicative of a seizure) in the fMRI BOLD (blood-oxygen-level dependant) response, which was completely absent from the EEG data (Kobayashi, Hawco, Grova, Dubeau, & Gotman, 2006). This is particularly striking in that this occurred despite the fact that the intense seizure activity occurred in a region where EEG electrodes were closely spaced. Kobayashi et al. note that this is striking as the EEG completely missed the most intensely discharging region despite the fact that this region was also located at the cortical level.”

Hmmm, I was sent this remarkable passage. I tried to log on the link that was provided at the top, but it did not work. I will only comment after having read the entire paper. 

Smithy
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#3
(01-28-2018, 10:18 AM)Smithy Wrote: Hmmm, I was sent this remarkable passage. I tried to log on the link that was provided at the top, but it did not work. I will only comment after having read the entire paper. 

Smithy

Possibly here?

https://www.skeptic.org.uk/magazine/onli...ing-brain/

Quote:Towards a Cognitive Neuroscience of the Dying Brain

Published in The Skeptic, Volume 21, Issue 2 (2008)

Jason J Braithwaite offers an in-depth analysis and critique of the survivalist’s neuroscience of near-death experiences

or maybe here may be better:
http://www.academia.edu/574245/Towards_a...ying_Brain
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#4
(01-28-2018, 10:40 AM)Typoz Wrote: Possibly here?

https://www.skeptic.org.uk/magazine/onli...ing-brain/


or maybe here may be better:
http://www.academia.edu/574245/Towards_a...ying_Brain

Yes, I got it now.

First of all, I saw that this paper is almost ten years old. I don't think much of what he says is valid nowadays.
But I will study it and come back to it later - but that "later" may be a days.

Cheers - Smithy
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#5
He (Braithwaite) like any mainstream British university psychologist, didn't like Van Lommel's paper (which was threatening to the party line) and felt duty bound to say something.

His main point was that electrodes on the scalp cannot be an infallible method of detecting deep brain activity that might be occurring even in the confirmation of a flat EEG. In Van Lommel's patient's though, there wouldn't have been any EEG in place to measure electrical activity, there isn't time for anything like that when a patient goes into cardiac arrest. (so we are told)

But they know that after a cardiac arrest, the brain stem ceases to function and without a brain stem the whole brain is off line so it doesn't matter about electrodes on the scalp or implanted electrodes deeper down in the brain, no brain stem, no nothing. 

Dr Van Lommel is quite approachable for questions of this nature and (Desperado) I would suggest you contact him.

 http://compellingevidencefortheafterlife...age_id=283

Through many studies with induced cardiac arrest in both human and animal models cerebral function has been shown to be severely compromised during cardiac arrest, with complete cessation of cerebral flow, causing sudden loss of consciousness and of all body reflexes (function of the cortex), but also with the abolition of all brain-stem activity with the loss of the gag reflex and the corneal reflex, and fixed and dilated pupils are clinical findings in those patients.

Edit : No disrespect to you Desperado but I'm personally bored with reiterating what's been said so many times before. It never makes any difference, the sceptics on here just ignore it and continue to accept what Braithwaite (and others like him ) have to say unconditionally.... even though Baithwaite and others have never conducted any serious research into this phenomenon other than reading a few papers and writing one of his own. How many hours does that take ? Not that many. 

Van Lommel, however spent years of hard slog with real patients on the hospital floor and followed them up afterwards for a decade to produce his study.

Why should Braithwaite's paper be given the same consideration as Van Lommel's.
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#6
(01-28-2018, 04:36 AM)Desperado Wrote: So anyone with a better grip on the functions of the brain have any opinion on Jason Braithwaite's references to EEG activity here: http://www.ukskeptics.com/the-dying-brain.php

“However, the emerging evidence is somewhat unhelpful for the survivalist. Tao, Ray, Hawes-Ebersole, and Ebersole (2005) compared EEG activity from surgically implanted electrodes placed in or around deep sub-cortical regions of epileptic patients, with cortical EEG electrodes placed on the scalp of the same patients. The results were quite surprising. Tao et al. showed that for 90% of cases, large amplitude paroxysmal firing needed to recruit 10 cm2 of brain tissue in order to show up against background cortical EEG traces. In other words, large seizure-based activity was being recorded by the surgically implanted electrodes (indexing clear and widespread brain-seizure activity) which was completely absent from scalp-based EEG traces until it propagated through and excited 10 cm2 of brain volume. This is a considerable amount of brain tissue.”

“Furthermore, a recent study that employed both EEG and brain-imaging (fMRI) techniques to explore seizure processes found significant increases in localised cortical neural activity (indicative of a seizure) in the fMRI BOLD (blood-oxygen-level dependant) response, which was completely absent from the EEG data (Kobayashi, Hawco, Grova, Dubeau, & Gotman, 2006). This is particularly striking in that this occurred despite the fact that the intense seizure activity occurred in a region where EEG electrodes were closely spaced. Kobayashi et al. note that this is striking as the EEG completely missed the most intensely discharging region despite the fact that this region was also located at the cortical level.”

You have to understand what scalp EEG is picking up. EEG scalp sensors are crude metal sensors which at any moment are picking up the summed post synaptic potential of around 1/2 million firing neurons from within the cortex. Bear in mind EEG is nowhere near sensitive enough to measure the actual firing of the neuron (it’s too quick), we’re only measuring the slower currents from the period after neurons have fired. To have any effect on the crude metal sensor on the scalp, you need the summed post synaptic potential of hundreds of thousands of neurons, and even then, we can only pick up this activity in the outermost layers of the brain, closest to the scalp. We can’t pick up anything deeper.

One needs to use invasive EEG (iEEG) to pickup weaker activity that would not be picked up by scalp EEG. iEEG uses probes that are inserted directly into the brain. That allows them to pick up weaker electrical fields, and because of their probe-like nature, they can be inserted at different depths into the brain, allowing measurements from deeper brain structures that are totally off limits to surface scalp EEG.

One needs to be clear about the uses of medical EEG, compared to research using iEEG. There are plenty of studies showing continued electrical activity in the brain using iEEG, when EEG on the surface of the scalp has gone flat. There are many different reasons why this can occur. Suffice it to say that it is totally incorrect to claim that there is no activity in the brain, simply because medical EEG cannot measure it.

However, one should also bear in mind that medical EEG measurements are generally accepted as being suitable to decide on whether somebody is conscious, or not. Finally bear in mind that studies like aware, are suggesting that people may still maintain some level of consciousness in situations previously thought impossible, that is that people may in some circumstances only *appear* to be behaviourally unconscious.

What is really the clincher, is whether people can recall information from these periods, information that they should not (could not) have become aware of because of their condition.

The use of targets is a great way to investigate whether people are coming into possession of information during these periods, in a way that we do not understand. The problem is that most studies looking into this question, end up hiding the targets, to overcome objections of information leakage.

There is a middle way... but no one on here seems to like it. Some information obtained during these periods may be anomalous, but at the same time, nothing (no entity etc) needs to have left the body.
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#7
(01-28-2018, 07:57 PM)Max_B Wrote: You have to understand what scalp EEG is picking up. EEG scalp sensors are crude metal sensors which at any moment are picking up the summed post synaptic potential of around 1/2 million firing neurons from within the cortex. Bare in mind EEG is nowhere near sensitive enough to measure the actual firing of the neuron (it’s too quick), we’re only measuring the slower currents from the period after neurons have fired. To have any effect on the crude metal sensor on the scalp, you need the summed post synaptic potential of hundreds of thousands of neurons, and even then, we can only pick up this activity in the outermost layers of the brain, closest to the scalp. We can’t pick up anything deeper.

One needs to use invasive EEG (iEEG) to pickup weaker activity that would not be picked up by scalp EEG. iEEG uses probes that are inserted directly into the brain. That allows them to pick up weaker electrical fields, and because of their probe-like nature, they can be inserted at different depths into the brain, allowing measurements from deeper brain structures that are totally off limits to surface scalp EEG.

One needs to be clear about the uses of medical EEG, compared to research using iEEG. There are plenty of studies showing continued electrical activity in the brain using iEEG, when EEG on the surface of the scalp has gone flat. There are many different reasons why this can occur. Suffice it to say that it is totally incorrect to claim that there is no activity in the brain, simply because medical EEG cannot measure it.

However, one should also bear in mind that medical EEG measurements are generally accepted as being suitable to decide on whether somebody is conscious, or not. Finally bear in mind that studies like aware, are suggesting that people may still maintain some level of consciousness in situations previously thought impossible, that is that people may in some circumstances only *appear* to be behaviourally unconscious.

What is really the clincher, is whether people can recall information from these periods, information that they should not (could not) have become aware of because of their condition.

The use of targets is a great way to investigate whether people are coming into possession of information during these periods, in a way that we do not understand. The problem is that most studies looking into this question, end up hiding the targets, to overcome objections of information leakage.

There is a middle way... but no one on here seems to like it. Some information obtained during these periods may be anomalous, but at the same time, nothing (no entity etc) needs to have left the body.

None of the above matters in cardiac arrest, Max (even if what you are saying did have any substance to it, which it doesn't BTW ref-Dr John Greenfield  http://skeptiko.com/eeg-expert-on-near-d...xperience/) because the brain stem doesn't function after the heart has stopped and the whole of the brain goes down. (Greenfield doesn't mention the brain stem of course)

Naturally you don't like the experiment that is being conducted because you know very well that if Parnia's patients see the pictures, your theory has finally been 'slain' once and for all.
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