New Bernardo Kastrup Paper: What Neuroimaging of the Psychedelic State Tells Us about the Mind-Body

#41
I've had a bit more time to process that 2012 paper. To me, Bernardo's error is to assume that reduced CBF to those parts of the brain found in the study represent some sort of neural correlates of consciousness, whereas all they really represent are neural correlates of psilocybin use.

Careful reading of this passage is key IMO:
Yeah, I agree, and what is really being observed is psilocybin's affect on their measurements... I stress 'measurements', because it's not known what neural activity BOLD is really correlated with.

Refreshing my understanding of fMRI BOLD this morning...

BOLD itself Is not really measuring oxygen use... CBF is thought to be related to neural activity... But BOLD is taking advantage of our knowledge that when CBF increases, it increases beyond the brains metabolic rate of oxygen utilisation (CMRO2). This causes a rise in localised capillary and venous oxygen levels.

It's that mismatch between CBF increase and CMRO2 change that the BOLD signal is related to.

Thus BOLD is reliant on knowing what neural activity is going on in the brain, to be able to make any assumption on what these measurements mean.

You can quickly see that a variety of changes could affect the BOLD 'mismatch' signal, that are not related to an increase in oxygen utilisation.

Irrespective of that, I still return to this odd assumption that 'richness' of experience somehow requires an increase in energy utilisation (now further confabulated by whether BOLD actually means that in this case) which makes very little sense to me.

Borjigin's study was conducted in an enforced physiological state of zero CBF, and therefore substantially reduced EM power measured by iEEG... and in that physiological state, she measured increased synchronization and connectivity which she states makes the organism appear *more* conscious during cardiac arrest, than during wakefulness.

I can't see anyway round that, which suggests one should be very careful about suggesting CBF is any sort of reliable measure of 'richness', irrespective of what BOLD means in this case regarding actual energy utilisation.
 
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#42
Irrespective of that, I still return to this odd assumption that 'richness' of experience somehow requires an increase in energy utilisation (now further confabulated by whether BOLD actually means that in this case) which makes very little sense to me.
However, if the scan had showed a wild increase of neural activity on psilocibin, I am sure that would have been seized as evidence that the brain was producing the trip experience!

The problem seems to be that so much brain research is indecisive, with multiple interpretations. Even the observation that electrical activity diminishes massively soon after a cardiac arrest, attracts the counter argument that some activity can still be detected, and maybe that might be 'enough' to explain NDE's! Of course it is easy to postulate that any level of electrical activity might be enough, because nobody knows how to translate electrical activity into consciousness - other than by correlation.

Does the richness of an experience translate into anything measurable in the brain?

http://www.scientificamerican.com/article/thinking-hard-calories/

David
 
#43
However, if brains were "whirlpools of consciousness" I might expect them to light up more during "richer experiences". ;)
 
#44
However, if the scan had showed a wild increase of neural activity on psilocibin, I am sure that would have been seized as evidence that the brain was producing the trip experience!

The problem seems to be that so much brain research is indecisive, with multiple interpretations. Even the observation that electrical activity diminishes massively soon after a cardiac arrest, attracts the counter argument that some activity can still be detected, and maybe that might be 'enough' to explain NDE's! Of course it is easy to postulate that any level of electrical activity might be enough, because nobody knows how to translate electrical activity into consciousness - other than by correlation.

Does the richness of an experience translate into anything measurable in the brain?

http://www.scientificamerican.com/article/thinking-hard-calories/

David
Well if energy is some sort of correlate of 'richness'... it seems to me more logical to talk about how the energy is used/arranged/interacts etc... rather than how much energy there is... but frankly I think the simplistic connection that is being put forward is a little too symplistic. :)
 
#45
Well if energy is some sort of correlate of 'richness'... it seems to me more logical to talk about how the energy is used/arranged/interacts etc... rather than how much energy there is... but frankly I think the simplistic connection that is being put forward is a little too symplistic. :)
In fairness, that's not quite what I think Bernardo is saying. Rather, I think he's saying that energy is needed in order to create the broader information state (see my post above).

By the way Bernardo - I hope you return to this thread!
 
#46
In fairness, that's not quite what I think Bernardo is saying. Rather, I think he's saying that energy is needed in order to create the broader information state (see my post above).

By the way Bernardo - I hope you return to this thread!
Eh?
 
#47
Sorry, not my last post, this one:

Here's where I'm having an issue. Bernardo writes:

Therefore, a relative increase in local metabolism is necessary to create the broader information space in the brain that supposedly constitutesthe broader information space in awareness entailed by richer experiences. This is an inescapable implication of physicalism.​

I've summarized the findings on the increased information relationships above. Am I wrong that it is those relationships that can be interpreted as forming the broader information state required for richer experiences that Bernardo refers to (and that are also required by integrated information theory?).

If so, wouldn't we have to accept that whatever the metabolic state of the brain at that time, it was sufficient to power that broader information state, thus resulting in the phenomenological experiences described.
 
#48
Sorry, not my last post, this one:
I dunno what your going on about Aroute? but he says... "...a relative increase in local metabolism is necessary to create... [ ] ...richer experiences."

But there is no reason to assume that is actually correct, although he seems to be saying he is assuming it to be correct for his argument... I assume this is because he wants an easy target to knock down.... Lol...
 
#49
I dunno what your going on about Aroute? but he says... "...a relative increase in local metabolism is necessary to create... [ ] ...richer experiences."

But there is no reason to assume that is actually correct, although he seems to be saying he is assuming it to be correct for his argument... I assume this is because he wants an easy target to knock down.... Lol...
Why did you remove "the broader information space"?

You wrote that "Well if energy is some sort of correlate of 'richness'." I wrote that in fairness, he's not really saying that. He says the energy is needed to create the information space. It is the information space which is the correlate of richness.

I agree there is no reason to assume it is true (as I said in my post). I was trying to clarify what Bernardo's actual position was.
 
#50
Additionally, is IIT even a physcialist theory? - I ask because it seems at times even the authors aren't clear on this.
I'm not sure whether Bernardo considered his argument to apply to IIT either, which is why I raised it in my post to him. He didn't comment on it. IIRC he's not a big fan of IIT either.
 
#51
Why did you remove "the broader information space"?

You wrote that "Well if energy is some sort of correlate of 'richness'." I wrote that in fairness, he's not really saying that. He says the energy is needed to create the information space. It is the information space which is the correlate of richness.

I agree there is no reason to assume it is true (as I said in my post). I was trying to clarify what Bernardo's actual position was.
I removed it because it's not necessary.
 
#52
I removed it because it's not necessary.
Well, only if you want to frame his argument properly. He wasn't focusing on the amount of energy as an NCC itself, which is what you seemed to be suggesting when you wrote: "it seems to me more logical to talk about how the energy is used/arranged/interacts etc... rather than how much energy there is". Bernardo wasn't just talking about how much energy there is, except so far as he believes that an increase of energy would be needed to create the information state needed for the richer experience.
 
S

Sciborg_S_Patel

#53
I'm not sure whether Bernardo considered his argument to apply to IIT either, which is why I raised it in my post to him. He didn't comment on it. IIRC he's not a big fan of IIT either.
Well any realism applied to "information" doesn't seem like a physicalist theory to me?

However, if the scan had showed a wild increase of neural activity on psilocibin, I am sure that would have been seized as evidence that the brain was producing the trip experience!

The problem seems to be that so much brain research is indecisive, with multiple interpretations. Even the observation that electrical activity diminishes massively soon after a cardiac arrest, attracts the counter argument that some activity can still be detected, and maybe that might be 'enough' to explain NDE's! Of course it is easy to postulate that any level of electrical activity might be enough, because nobody knows how to translate electrical activity into consciousness - other than by correlation.

Does the richness of an experience translate into anything measurable in the brain?

http://www.scientificamerican.com/article/thinking-hard-calories/

David
Yeah, I think we need to be sure to separate the kind of theories the (obviously brief) paper is an argument against versus alternate [metaphysical] interpretations the paper is not considering.

In general I think if look at the way materialist/physicalist theories have shifted over time to take refuge in computer inspired functionalism separating thoughts/emotions from specific structures the idea that we are eventually going to find empirical evidence to falsify the whole thing isn't surprising.

When people talk of Patterns (and connectivity just seems like a synonym for patterns?) I think we're talking about something the paper isn't discussing.

Even the shift from Physicalism to Patternism is rather incredible given the last one doesn't rule out things like reincarnation.
 
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#54
Well, only if you want to frame his argument properly. He wasn't focusing on the amount of energy as an NCC itself, which is what you seemed to be suggesting when you wrote: "it seems to me more logical to talk about how the energy is used/arranged/interacts etc... rather than how much energy there is". Bernardo wasn't just talking about how much energy there is, except so far as he believes that an increase of energy would be needed to create the information state needed for the richer experience.
I still don't know what your going on about... it's absolutely clear that he's saying a relative increase in metabolism is required for richness.
 
#55
Well if energy is some sort of correlate of 'richness'... it seems to me more logical to talk about how the energy is used/arranged/interacts etc... rather than how much energy there is... but frankly I think the simplistic connection that is being put forward is a little too symplistic. :)
I don't think that most of the action in profound psychedelic trips happens inside the brain. I think these trips are related to the whole NDE phenomenon, although the physical mental separation isn't as total - for example even people on DMT trips report opening their eyes and seeing whatever they are encountering overlaid over the normal world!

David
 
#56
I don't think that most of the action in profound psychedelic trips happens inside the brain. I think these trips are related to the whole NDE phenomenon, although the physical mental separation isn't as total - for example even people on DMT trips report opening their eyes and seeing whatever they are encountering overlaid over the normal world!

David
I dunno what they are... I haven't spent a great deal of time thinking about them... but they seem to be capable of distorting and disrupting patterns of activation within the networks.

Dunno whether they are useful or not... perhaps in some people they are. My one experimentation with some good quality marijuana at my mothers flat, resulted in a bizzare visual sensory delay, and subsequent paranoia, where I thought men with guns were going to break into the flat.

Following that I had about 6 weeks of inability to focus on problems to solve them, my mind would sort of slide off problems, with an inability to find any sort of solution, which I found quite frustrating. I likened it to losing the razor edge of my mind... it felt blunted.

Some years later, I was advised not to take them again, to avoid risks to my mental health... I didn't need the warning, lol, I wouldn't put myself through that again voluntarily!
 
#57
I don't think that most of the action in profound psychedelic trips happens inside the brain. I think these trips are related to the whole NDE phenomenon, although the physical mental separation isn't as total - for example even people on DMT trips report opening their eyes and seeing whatever they are encountering overlaid over the normal world!

David
Wouldn't that be consistent in what we see in the LSD paper? It describes a bunch of additional information going into the primary visual cortex. Is it surprising it will mix in with the other stuff that's being seen?
 
S

Sciborg_S_Patel

#58
Wouldn't that be consistent in what we see in the LSD paper? It describes a bunch of additional information going into the primary visual cortex. Is it surprising it will mix in with the other stuff that's being seen?
What is information in the context you are using it? Something that reduces to physicalist primitives or something additional to those?
 
#59
What is information in the context you are using it? Something that reduces to physicalist primitives or something additional to those?
In a way, neither. Rather, I see them as different sides of the same coin. In other worlds, different ways of describing the properties of the same stuff. I guess you could call them equal. They are all fundamental properties (or at least as fundamental as we've identified so far...)
 
#60
Yeah, I agree, and what is really being observed is psilocybin's affect on their measurements... I stress 'measurements', because it's not known what neural activity BOLD is really correlated with.

Refreshing my understanding of fMRI BOLD this morning...

BOLD itself Is not really measuring oxygen use... CBF is thought to be related to neural activity... But BOLD is taking advantage of our knowledge that when CBF increases, it increases beyond the brains metabolic rate of oxygen utilisation (CMRO2). This causes a rise in localised capillary and venous oxygen levels.

It's that mismatch between CBF increase and CMRO2 change that the BOLD signal is related to.

Thus BOLD is reliant on knowing what neural activity is going on in the brain, to be able to make any assumption on what these measurements mean.

You can quickly see that a variety of changes could affect the BOLD 'mismatch' signal, that are not related to an increase in oxygen utilisation.

Irrespective of that, I still return to this odd assumption that 'richness' of experience somehow requires an increase in energy utilisation (now further confabulated by whether BOLD actually means that in this case) which makes very little sense to me.

Borjigin's study was conducted in an enforced physiological state of zero CBF, and therefore substantially reduced EM power measured by iEEG... and in that physiological state, she measured increased synchronization and connectivity which she states makes the organism appear *more* conscious during cardiac arrest, than during wakefulness.

I can't see anyway round that, which suggests one should be very careful about suggesting CBF is any sort of reliable measure of 'richness', irrespective of what BOLD means in this case regarding actual energy utilisation.
I was trying to explain what BOLD was measuring to a friend yesterday... (i.e. BOLD = vascular increase, minus, oxygen utilisation), and it's limitations, because it measures neither of those two things, but only the difference between them.

Thus it's not clear which of those two things (or both) have altered from BOLD measurement to BOLD measurement, to produce an increase (or decrease) in the difference between them.

The best (inaccurate) analogy I could come up with was that BOLD was taking a snapshot of the number of petrol tankers waiting outside a neuron... Which were waiting to refuel it. Also, BOLD couldn't tell you how many tankers there were waiting outside the neuron at any one snapshot, all BOLD could tell you were whether the number of tankers had gone up (or down) in relation to a previous snapshot.

Dunno if that is useful to anybody...?
 
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