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[GE Morton]

Gertie . . .

You might find two articles in this week's issue of Science of interest --- both on the structural neural correlates of consciousness in birds. The editors' summary article is below. (The two research articles are too long to post here).

-------------------

Birds do have a brain cortex—and think

Like mammals, birds have a pallium that sustains correlates of consciousness

By Suzana Herculano-Houzel *

The term “birdbrain” used to be derogatory. But humans, with their limited brain size, should have known better than to use the meager proportions of the bird brain as an insult. Part of the cause for derision is that the mantle, or pallium, of the bird brain lacks the obvious layering that earned the mammalian pallium its “cerebral cortex” label. However, birds, and particularly corvids (such as ravens), are as cognitively capable as monkeys (1) and even great apes (2). Because their neurons are smaller, the pallium of songbirds and parrots actually comprises many more information-processing neuronal units than the equivalent-sized mammalian cortices (3). On page 1626 of this issue, Nieder et al. (4) show that the bird pallium has neurons that represent what it perceives—a hallmark of consciousness. And on page 1585 of this issue, Stacho et al. (5) establish that the bird pallium has similar organization to the mammalian cortex.

The studies of Nieder et al. and Stacho et al. are noteworthy in their own ways, but not because either is the first demonstration of
close parallels between mammalian and bird pallia. That neuroscientists still refer to how bird cognition happens “without a cerebral
cortex” (6), as Nieder et al. have done themselves (4), is a testament to how neuroscience has grown so much that specialists in different subfields often are not familiar with each other’s findings, even when groundbreaking.

Stating that birds do not have a cerebral cortex has been doubly wrong for several years. Birds do have a cerebral cortex, in the
sense that both their pallium and the mammalian counterpart are enormous neuronal populations derived from the same dorsal half of the second neuromere in neural tube development (7). The second neuromere is important: The pallium of birds and mammals lies posterior to the hypothalamus, the true front part of the brain, which is then saddled in development by the rapidly bulging pallium. Owing to the painstaking, systematic comparative analyses of expression patterns of multiple homeobox (Hox) genes that compartmentalize embryonic development, it is now understood that in both birds and mammals, the pallium rests on top of all the neuronal loops formed
between spinal cord, hindbrain, midbrain, thalamus, and hypothalamus.

In both birds and mammals, the pallium is the population of neurons that are not a necessary part of the most fundamental circuits that operate the body. But because the pallium receives copies, through the thalamus, of all that goes on elsewhere, these pallial neurons create new associations that endow animal behavior with flexibility and complexity. So far, it appears that the more neurons there are in the pallium as a whole, regardless of pallial, brain, or body size, the more cognitive capacity is exhibited by the animal (8). Humans remain satisfyingly on top: Despite having only half the mass of an elephant pallium, the human version still has three times its number of neurons, averaging 16 billion (9). Corvids and parrots have upwards of half a billion neurons in their pallia and can have as many as 1 or 2 billion—like monkeys (3).

Additionally, it has been known since 2013 that the circuits formed by the pallial neurons are functionally organized in a similar
manner in birds as they are in mammals (10). Using resting-state neuroimaging to infer functional connectivity, the pigeon pallium was shown to be functionally organized and internally connected just like a mouse, monkey, or human pallium, with sensory areas, effector areas, richly interconnected hubs, and highly associative areas in the hippocampus and nidopallium caudolaterale.
The nidopallium caudolaterale is the equivalent of the monkey prefrontal cortex (10), the portion of the pallium that is the seat of the ability to act on thoughts, feelings, and decisions, according to the current reality informed by the senses.

Now, adding to their resting-state neuroimaging tool set the power and high resolution of polarized light microscopy to examine anatomical connectivity, Stacho et al. show that the pallia of pigeons and owls, like that of mice, monkeys, and humans, is criss-crossed by fibers that run in orthogonal planes. Repeated imaging of the brain with light shone at different orientations revealed that fibers within and across bird pallial areas are mostly (although not exclusively) organized at right angles, reminiscent of the orthogonal tangential and radial organization of cortical fibers in mammals (11). The broadminded neuroscientist with some knowledge of developmental biology might not find this surprising; what would be the alternative, a spaghetti-like disorganized jumble of fibers? But then again, the mantra that “birds do not have a cortex” even though they share pallial development and organization with mammals has been repeated so exhaustively that recognizing that columns and layers are actually observed—visible under polarized light if not to the naked eye—brings new hope that this mantra will join the ranks of myth.

If the bird pallium as a whole is organized just like the mammalian pallium, then it follows that the part of the bird pallium that
is demonstrably functionally connected like the mammalian prefrontal pallium (the nidopallium caudolaterale) should also function like it. Nieder et al., who established previously that corvids, like macaques, have sensory neurons that represent numeric quantities (12), now move on to this associative part of the bird pallium. They find that, like the macaque prefrontal cortex, the associative pallium of crows is rich in neurons that represent what the animals next report to have seen—whether or not that is what they were shown.

This representation develops over the time lapse of 1 to 2 s between the stimulus disappearing and the animal reporting what it perceived by pecking at a screen either for “yes, there was a stimulus” or for “no, there was no stimulus,” depending on a variable
contingency rule. The early activity of these neurons still reflects the physical stimulus presented to the animal, which indicates that
they receive secondhand sensory signals. However, as time elapses and (presumably) recurrent, associative cortical circuits progressively shape neuronal activity, the later component of the responses of the same neurons predicts instead what the animal then
reports: Did it see a stimulus that indeed was there, or did it think the stimulus was there enough to report it—even if it was not?
Future studies will certainly delve into more complex mental content than simply “Was it there or not?”, but concluding that birds do
have what it takes to display consciousness—patterns of neuronal activity that represent mental content that drives behavior—now
appears inevitable.

Because the common ancestor to birds (and non-avian reptiles) and mammals lived 320 million years ago, Nieder et al. infer that
consciousness might already have been present then—or might have appeared independently in birds and mammals through convergent evolution. Those hypotheses miss an important point: how fundamental properties of life present themselves at different scales. The widespread occurrence of large mammalian bodies today does not mean that ancestral mammals were large (they were not), nor do the nearly ubiquitous folded cortices of most large mammals today imply that the ancestral cortex was folded [it was not (13)]. The physical properties that make self-avoiding surfaces buckle and fold as they expand under unequal forces apply equally to tiny and enormous cortices, but folds only present themselves past a certain size (14). Expansion of the cortical surface relative to its thickness is required for folds to appear. But that does not imply that folding evolved, because the physical principles that cause it to emerge were always there.

Perhaps the same is true of consciousness: The underpinnings are there whenever there is a pallium, or something connected like a
pallium, with associative orthogonal shortand long-range loops on top of the rest of the brain that add flexibility and complexity
to behavior. But the level of that complexity, and the extent to which new meanings and possibilities arise, should still scale with the
number of units in the system. This would be analogous to the combined achievements of the human species when it consisted of just
a few thousand individuals, versus the considerable achievements of 7 billion today.

REFERENCES AND NOTES
1. E. L. MacLean et al., Proc. Natl. Acad. Sci. U.S.A.111, 2140
(2014).
2. C. Kabadayi, L. A. Taylor, A. M. P. von Bayern, M. Osvath, R.
Soc. Open Sci.3, 160104 (2016).
3. S. Olkowicz et al., Proc. Natl. Acad. Sci. U.S.A.113, 7255
(2016).
4. A. Nieder et al., Science369, 1626 (2020).
5. M. Stacho et al., Science369, eabc5534 (2020).
6. O. Güntürkün, T. Bugnyar, Trends Cogn. Sci.20, 291 (2016).
7. L. Puelles, M. Harrison, G. Paxinos, C. Watson, Trends
Neurosci.36, 570 (2013).
8. S. Herculano-Houzel, Curr. Opin. Behav. Sci.16, 1 (2017).
9. S. Herculano-Houzel, The Human Advantage (MIT Press,
2016).
10. M. Shanahan, V. P. Bingman, T. Shimizu, M. Wild, O.
Güntürkün, Front. Comput. Neurosci.7, 89 (2013).
11. V. J. Wedeen et al., Science335, 1628 (2012).
12. A. Nieder, Curr. Opin. Behav. Sci.16, 8 (2017).
13. T. B. Rowe, T. E. Macrini, Z.-X. Luo, Science332, 955 (2011).
14. B. Mota, S. Herculano-Houzel, Science349, 74 (2015).
10.1126/science.abe0536

* Department of Psychology, Department of Biological Sciences, Vanderbilt Brain Institute, Vanderbilt University,
Nashville, TN, USA. Email: suzana.herculano@vanderbilt.edu

[Gertie]

GE

Interesting, thanks. Tiny neurons! Does your idea rest on a central 'control and command' structure in complex conscious creatures? A Cartesian Theatre minus the homunculous? Do we have sufficient evidence for such a thing?

The How can you know question still applies. And I think is only exacerbated by (rightly) accepting that all we have is a necessarily limited and flawed model of our own making to work with.

We can't know that the cognitive model theory is "right," i.e., true or false. It's just a theory, and theories are never true or false. They're only good or bad, sound or unsound, depending upon how well unify and render coherent some set of phenomena, suggest future observations, and correctly predict their results. They're explanatory constructs.

It's a What if... which doesn't follow the usual ways we arrive at scientifically grounded theories. And which we can't reliably test because experience is private. And because it's not an explanation which tells us the necessary and sufficient conditions which might be third person observable, we can't test for those either.

That aside, the question remains of how brain matter can generate experience, what is it about brains in certain states that does it and why. And how does generated experience feed back information to brain matter.

Well, that sounds like you're asking for a reductive explanation, which, for the reasons given --- per that theory --- will be forever unobtainable.

Then it doesn't avoid the Hard Problem?


Or another problem with monist materialist identity theory - it seems to render experience redundant. If the material brain is doing the necessary behavioural work anyway, why would parallel experience evolve? Over determinism.


Your solution has the additional 'reporting back/presenting itself' aspect too. If there isn't a homunculous watching the experience the brain creates play out, behaviourally it's all only neurons interacting. To take the bee analogy, how would invisible honey affect the bee's behaviour?

Conversely, I don't think this necessarily precludes this generating of experience being a universal aspect of all matter.

That is another theory. But if there is no way to test, to determine, whether or not rocks (for example) have experience, then the theory is vacuous. It will not lead us to any new knowledge.

Just because we don't have a reliable test doesn't mean we can discount a theory with similar explanatory value as your preference - which we can't reliably test either.

[GE Morton]

Interesting, thanks. Tiny neurons! Does your idea rest on a central 'control and command' structure in complex conscious creatures? A Cartesian Theatre minus the homunculous? Do we have sufficient evidence for such a thing?

I think such a structure is logically implied. Decision-making has to occur somewhere. That structure is the "homunculus." What it perceives, and takes to be "reality," is the model, created and presented to it by other structures. There is plenty of room in the brain for both.

It's a What if... which doesn't follow the usual ways we arrive at scientifically grounded theories. And which we can't reliably test because experience is private. And because it's not an explanation which tells us the necessary and sufficient conditions which might be third person observable, we can't test for those either.

The only available tests are of the system's behavior. We can observe whether particular brain subsystems play the role the theory ascribes to them by disabling them and observing the effects on behavior. But no theory will be able to characterize "what it's like" to be a bat, or a crow, or even another human. We can only make inferences --- guesses --- about that, based on what it's like to be us, and similarities of others' behavior to ours. And we have plenty of behavioral evidence indicating that "what it is like" to be Mother Teresa is considerably different than "what it is like" to be Adolf Hitler (not to mention the ancient, unsolved problem of men trying to understand women, and vice-versa).

Or another problem with monist materialist identity theory - it seems to render experience redundant. If the material brain is doing the necessary behavioural work anyway, why would parallel experience evolve? Over determinism.

Subjective experience is not "parallel" to (certain) brain functioning. It is a feature of it, a product of it. It is an epiphenomenon only in the sense that an EM field is an epiphenomenon of electric motors. It's existence does not require, or imply, another realm of "substances" in the universe. Nor is it redundant --- there is no question that conscious mental events (decisions, intentions, desires), not non-conscious neural processes, initiate most human behavior (though non-conscious processes trigger some). Of course, we can ask why do certain physical processes produce that effect, but that is an unanswerable question --- like asking why electrons have negative charge, or why the speed of light is C.

Your solution has the additional 'reporting back/presenting itself' aspect too. If there isn't a homunculous watching the experience the brain creates play out, behaviourally it's all only neurons interacting. To take the bee analogy, how would invisible honey affect the bee's behaviour?

I think I said before that the "Cartesian theater, without the homunculus," was gaining new favor among some psychologists and neuro-scientists. But there is no need to banish the homunculus. Another brain system can fulfill that role.

[Faustus5]

Subjective experience is not "parallel" to (certain) brain functioning. It is a feature of it, a product of it. It is an epiphenomenon only in the sense that an EM field is an epiphenomenon of electric motors. It's existence does not require, or imply, another realm of "substances" in the universe.

But an EM field can be intersubjectively confirmed to actually exist, and subjective experiences (in this sense) cannot. So it kind of requires another, inexplicable realm or mode of being.

I think TS's approach, that subjective experiences are just how a subject witnesses and talks about her own brain events, makes more sense and is more consistent with a scientific/materialist model of the world.

I just don't think we need the extra step of thinking brain events, in addition to having all the causal properties we can observe from the third person, also generate something else that can't be measured and have no further effects in the world. That strikes me as problematic. What does this move accomplish? Why would evolution evolve the ability of the brain to generate these pointless effects?

[Sculptor1]

Subjective experience is not "parallel" to (certain) brain functioning. It is a feature of it, a product of it. It is an epiphenomenon only in the sense that an EM field is an epiphenomenon of electric motors. It's existence does not require, or imply, another realm of "substances" in the universe.

But an EM field can be intersubjectively confirmed to actually exist, and subjective experiences (in this sense) cannot. So it kind of requires another, inexplicable realm or mode of being.

You are setting up a completely false distinction. The point is that you cannot know what it feels like to be an EM field in the same way you cannot feel another's experience. Both can be confirmed to exist.

I just don't think we need the extra step of thinking brain events, in addition to having all the causal properties we can observe from the third person, also generate something else that can't be measured and have no further effects in the world. That strikes me as problematic. What does this move accomplish? Why would evolution evolve the ability of the brain to generate these pointless effects?

Why do you think this question is even meaningful. Evolution does not happen FOR a reason. The whole point of evolution is that it is the result of change, not a force to cause it.
And what makes you think that we are talking about pointless effects?

[Gertie]

GE

To take the homunculous self observing the Cartesian 'experiential field' idea then.

Obviously we should expect to discover brain mechanisms which account for the structural ways human experience manifests - a unified, discrete, coherent field of consciousness with the ability to focus attention, correlated with a first person pov located in a specific body.

As I understand it, your suggestion is that a specific part of human brains is effectively an experiential model of the Self-as-Experiencer (homunculous), assessing the incoming sensory qualia, reasoning, checking memory, imagining scenarios/consequences, and such. And then making decisions and issuing commands to the motor systems. And this Experiencer-Self part of the brain mainifests experientially too.

If that was the case, isn't that what we'd see on brain scans? Intense activity in this central control and command area whenever we are conscious, with a radial map of routes leading from sensory subsystems and to motor subsystems? Something like a wheel hub with spokes.

But that's not what scans find. If they had, that would be our understanding of how brains work.

Instead, scans find what experience feels like. Different subsystems dominating from moment to moment, as one or another gains attentional ascendance. Right now I'm concentrating on constructing this post, the corresponding part of my brain would be lighting up on a scan, while other subsystems which aren't the 'focus of my attention' right now would likely dim. Or if I'm listening to music I love my other subsystems take a breather, if I'm remembering something vividly, my current sensations fade, etc.

Attention and focus on this or that subsystem seems to be how brains work, not everything is always present like a film being played in a Cartesian Theatre for the Self-Experiencer to take in and assess. The attention process happens automatically, unless I feel I 'intervene' and deliberately shift it.

The reporting back issue has these experiential qualia being experientially observed by the Self-Experiencer, which still has to somehow report back to the physical brain systems, if the experience is a product of brains, rather than identical with brains. It's not a way out of that problem.

Which brings us to over determinism. The 'experiential field' as a product of brain activity only avoids this problem if neural correlation doesn't hold surely. Is that your claim? That brain activity produces an 'experiential field' which then somehow escapes neural correlates? But somehow causes physical neural activity

[Sculptor1]

GE

To take the homunculous self observing the Cartesian 'experiential field' idea then.

Obviously we should expect to discover brain mechanisms which account for the structural ways human experience manifests - a unified, discrete, coherent field of consciousness with the ability to focus attention, correlated with a first person pov located in a specific body.

As I understand it, your suggestion is that a specific part of human brains is effectively an experiential model of the Self-as-Experiencer (homunculous), assessing the incoming sensory qualia, reasoning, checking memory, imagining scenarios/consequences, and such. And then making decisions and issuing commands to the motor systems. And this Experiencer-Self part of the brain mainifests experientially too.

If that was the case, isn't that what we'd see on brain scans? Intense activity in this central control and command area whenever we are conscious, with a radial map of routes leading from sensory subsystems and to motor subsystems? Something like a wheel hub with spokes.

Why would you think that? LOL

But that's not what scans find. If they had, that would be our understanding of how brains work.

And no one expected to find any spokes or hubs, why should they?

Instead, scans find what experience feels like.

No. Scans SHOW cerebral activity which of experience which is consistent with similar or the same types of experience; ie. speech effect, visual effects, pleasure effects and so on light up specific areas of the cerebral cortex. as would be expected.

Different subsystems dominating from moment to moment, as one or another gains attentional ascendance. Right now I'm concentrating on constructing this post, the corresponding part of my brain would be lighting up on a scan, while other subsystems which aren't the 'focus of my attention' right now would likely dim. Or if I'm listening to music I love my other subsystems take a breather, if I'm remembering something vividly, my current sensations fade, etc.

Attention and focus on this or that subsystem seems to be how brains work, not everything is always present like a film being played in a Cartesian Theatre for the Self-Experiencer to take in and assess. The attention process happens automatically, unless I feel I 'intervene' and deliberately shift it.

The reporting back issue has these experiential qualia being experientially observed by the Self-Experiencer, which still has to somehow report back to the physical brain systems, if the experience is a product of brains, rather than identical with brains. It's not a way out of that problem.

A sculpture of Caesar is made of marble, marble is not the same as the sculpture of Caesar. So what, and how the brain is acting, in the sense of how it is structuring, how it is making connections, and what it the energetic state of down to microscopic levels is the experience, details impossible to see with a scanner. And since a scanner is not a brain, we ought to expect only a very partial understanding of the "experience" just by looking at pretty pictures from afar - because the scanner is no better.

Which brings us to over determinism. The 'experiential field' as a product of brain activity only avoids this problem if neural correlation doesn't hold surely. Is that your claim? That brain activity produces an 'experiential field' which then somehow escapes neural correlates? But somehow causes physical neural activity

The experience IS the neural activity. That is what a brain does.

[Gertie]

GE

To take the homunculous self observing the Cartesian 'experiential field' idea then.

Obviously we should expect to discover brain mechanisms which account for the structural ways human experience manifests - a unified, discrete, coherent field of consciousness with the ability to focus attention, correlated with a first person pov located in a specific body.

As I understand it, your suggestion is that a specific part of human brains is effectively an experiential model of the Self-as-Experiencer (homunculous), assessing the incoming sensory qualia, reasoning, checking memory, imagining scenarios/consequences, and such. And then making decisions and issuing commands to the motor systems. And this Experiencer-Self part of the brain mainifests experientially too.

If that was the case, isn't that what we'd see on brain scans? Intense activity in this central control and command area whenever we are conscious, with a radial map of routes leading from sensory subsystems and to motor subsystems? Something like a wheel hub with spokes.

Why would you think that? LOL

But that's not what scans find. If they had, that would be our understanding of how brains work.

And no one expected to find any spokes or hubs, why should they?

Instead, scans find what experience feels like.

No. Scans SHOW cerebral activity which of experience which is consistent with similar or the same types of experience; ie. speech effect, visual effects, pleasure effects and so on light up specific areas of the cerebral cortex. as would be expected.

Different subsystems dominating from moment to moment, as one or another gains attentional ascendance. Right now I'm concentrating on constructing this post, the corresponding part of my brain would be lighting up on a scan, while other subsystems which aren't the 'focus of my attention' right now would likely dim. Or if I'm listening to music I love my other subsystems take a breather, if I'm remembering something vividly, my current sensations fade, etc.

Attention and focus on this or that subsystem seems to be how brains work, not everything is always present like a film being played in a Cartesian Theatre for the Self-Experiencer to take in and assess. The attention process happens automatically, unless I feel I 'intervene' and deliberately shift it.

The reporting back issue has these experiential qualia being experientially observed by the Self-Experiencer, which still has to somehow report back to the physical brain systems, if the experience is a product of brains, rather than identical with brains. It's not a way out of that problem.

A sculpture of Caesar is made of marble, marble is not the same as the sculpture of Caesar. So what, and how the brain is acting, in the sense of how it is structuring, how it is making connections, and what it the energetic state of down to microscopic levels is the experience, details impossible to see with a scanner. And since a scanner is not a brain, we ought to expect only a very partial understanding of the "experience" just by looking at pretty pictures from afar - because the scanner is no better.

Which brings us to over determinism. The 'experiential field' as a product of brain activity only avoids this problem if neural correlation doesn't hold surely. Is that your claim? That brain activity produces an 'experiential field' which then somehow escapes neural correlates? But somehow causes physical neural activity

The experience IS the neural activity. That is what a brain does.

I'm addressing GE's homunculus idea. Tell it to him.

[GE Morton]

Subjective experience is not "parallel" to (certain) brain functioning. It is a feature of it, a product of it. It is an epiphenomenon only in the sense that an EM field is an epiphenomenon of electric motors. It's existence does not require, or imply, another realm of "substances" in the universe.

But an EM field can be intersubjectively confirmed to actually exist, and subjective experiences (in this sense) cannot. So it kind of requires another, inexplicable realm or mode of being.

Well, though you qualified your claim with "kind of," it is still a non sequitur. That some phenomena are subjective (not observable by third parties) is an epistemological fact, but epistemological facts don't entail any ontological facts. We can just as easily account for those phenomena as predictable effects of certain physical processes. Because they are the mode via which external information is represented internally in the system they are necessarily unobservable externally. Per Occam, "don't multiply entities needlessly."

I think TS's approach, that subjective experiences are just how a subject witnesses and talks about her own brain events, makes more sense and is more consistent with a scientific/materialist model of the world.

As I've pointed out before, that begs the question. The question of whether two (alleged) things are identical can only be answered on the basis of what we perceive, or "witness." If they appear different then we have to assume they are different, unless we can reconcile the apparent differences as due to differences in observational circumstances. That can't be done re: qualia and brain states. So we're not warranted in claiming them to be identical. But that they are not identical doesn't mean there is no essential and intimate relationship between them. There is. Qualia are "physical/materialist effects," even though they are subjective.

I just don't think we need the extra step of thinking brain events, in addition to having all the causal properties we can observe from the third person, also generate something else that can't be measured and have no further effects in the world.

Qualia can be measured in certain ways --- duration, intensity --- by the person experiencing them, though not by third parties (who may be able to measure the brain processes correlated with them). And they do have ubquitous effects in the world. A decision by me to post this comment --- a mental phenmenon --- caused my fingers to move over my keyboard. That is the only cause of that behavior I can know of directly --- though I'm the only one who can know that. Everyone else may only infer that some such decision was made.

[Faustus5]

Both can be confirmed to exist.

Can they both be confirmed to exist through intersubjective processes?

And what makes you think that we are talking about pointless effects?

Please articulate how something that has been described as "epiphenomenal" can have a point or a meaningful causal role to play.

[Faustus5]

A decision by me to post this comment --- a mental phenmenon --- caused my fingers to move over my keyboard. That is the only cause of that behavior I can know of directly --- though I'm the only one who can know that.

I appreciate that you are trying to approach qualia in a non-dualist fashion that remains consistent with scientific inquiry, but I'm still smelling dualism almost every time you describe such things, as in the above quote.

An uncharitable reading of this quote of yours suggests that you picture first a mental event in the world, then you imagine that this mental event creates a cascade of brain events leading eventually to activity in the motor sections of your brain guiding your fingers on the keyboard.

That is clearly dualism, but this isn't how you want me to interpret your two sentences, hence my characterizing it as an unfair interpretation.

So how should we interpret such an event?

In terms of causality consistent with cognitive neuroscience, we do not have a mental event causing physical events. In fact, we cannot have
that. We have physical brain events all the way down, period, with only the initiating brain event being a conscious event, and conscious only by virtue of the fact that it was registered in the short term memory of the brain's global workspace, another series of completely physical processes.

I don't see any need to multiply entities and add to all of this that there was a special epiphenomenal (and therefore pointless and non-functional) "glow" emitted by some of the brain processes that created a mental phenomenon.

[GE Morton]

GE

To take the homunculous self observing the Cartesian 'experiential field' idea then.

Obviously we should expect to discover brain mechanisms which account for the structural ways human experience manifests - a unified, discrete, coherent field of consciousness with the ability to focus attention, correlated with a first person pov located in a specific body.

As I understand it, your suggestion is that a specific part of human brains is effectively an experiential model of the Self-as-Experiencer (homunculous), assessing the incoming sensory qualia, reasoning, checking memory, imagining scenarios/consequences, and such. And then making decisions and issuing commands to the motor systems. And this Experiencer-Self part of the brain mainifests experientially too.

Not quite (or perhaps this is only a terminological quibble). The "homunculus" (the subsystem which assesses the information represented in the model and initiates actions) is not per se represented in the model, and is not aware of itself as a brain subsystem. What it recognizes as "itself" is "that which is having these experiences," plus the representation of the organism as a whole in the model. (In other words, the brain system which apprehends the model is not aware of its own workings).

If that was the case, isn't that what we'd see on brain scans? Intense activity in this central control and command area whenever we are conscious, with a radial map of routes leading from sensory subsystems and to motor subsystems? Something like a wheel hub with spokes.

That would depend upon how that subsystem is distributed. The "homunculus" may not be localized in a particular brain area.

But that's not what scans find. If they had, that would be our understanding of how brains work.

Instead, scans find what experience feels like. Different subsystems dominating from moment to moment, as one or another gains attentional ascendance. Right now I'm concentrating on constructing this post, the corresponding part of my brain would be lighting up on a scan, while other subsystems which aren't the 'focus of my attention' right now would likely dim. Or if I'm listening to music I love my other subsystems take a breather, if I'm remembering something vividly, my current sensations fade, etc.

Inputs over the different sensory channels (vision, olfactory, tactile, etc.) deliver their signals to specific areas of the brain, for preliminary processing. Those areas will "light up" on scans when there is input over those channels. But as far as I know there is no "part of the brain" that corresponds to "concentrating on constructing this post." At best the scans can reveal that you're concentrating on something. But if you have a link to some work that indicates otherwise, please post.

Attention and focus on this or that subsystem seems to be how brains work, not everything is always present like a film being played in a Cartesian Theatre for the Self-Experiencer to take in and assess. The attention process happens automatically, unless I feel I 'intervene' and deliberately shift it.

Keep in mind that even at the Orpheum, your attention is directed to specific things/events on the screen from moment to moment. But the entire screen is always before you.

The reporting back issue has these experiential qualia being experientially observed by the Self-Experiencer, which still has to somehow report back to the physical brain systems, if the experience is a product of brains, rather than identical with brains. It's not a way out of that problem.

That is only a problem if you're imagining the homunculus to be something separate from the brain. But it isn't; it is intimately connected to it, but not identical with it.

Which brings us to over determinism. The 'experiential field' as a product of brain activity only avoids this problem if neural correlation doesn't hold surely. Is that your claim? That brain activity produces an 'experiential field' which then somehow escapes neural correlates? But somehow causes physical neural activity

Oh, no. Phenomenal experience is strongly correlated with brain states; the former only exists as long as the latter does. But correlation is not identity, and does not entail it.

The chief architect of the "Self-Model Theory of Subjectivity" is Thomas Metzinger (no, this theory was not invented by me!). His book, "Being No One, The Self-Model Theory of Subjectivity" is here (among many other places):

https://www.amazon.com/Being-No-One-Sel ... 0262633086

A precis by Metzinger is here:

https://citeseerx.ist.psu.edu/viewdoc/d ... 1&type=pdf

[GE Morton]

A decision by me to post this comment --- a mental phenmenon --- caused my fingers to move over my keyboard. That is the only cause of that behavior I can know of directly --- though I'm the only one who can know that.

I appreciate that you are trying to approach qualia in a non-dualist fashion that remains consistent with scientific inquiry, but I'm still smelling dualism almost every time you describe such things, as in the above quote.

An uncharitable reading of this quote of yours suggests that you picture first a mental event in the world . . .

"Mental event in the world"? That's an odd phrase. Usually we reserve "in the world" to denote phenomena outside ourselves.

. . . then you imagine that this mental event creates a cascade of brain events leading eventually to activity in the motor sections of your brain guiding your fingers on the keyboard.

Yes.

That is clearly dualism, but this isn't how you want me to interpret your two sentences, hence my characterizing it as an unfair interpretation.

It is only dualism if you construe that mental event to be a non-physical phenomenon. My argument is that it isn't; it is a physical phenomenon, though one that is not reducible to other physical phenomena for explicable, understandable reasons.

In terms of causality consistent with cognitive neuroscience, we do not have a mental event causing physical events.

Yes; Dennett et al would so claim. But that claim is palpably false, as everyone who has ever had a thought, made a decision, formed an opinion, reached a judgment will confidently testify. I know without doubt, as did Descartes, that my actions are caused by acts of will (i.e., mental events). There is nothing of which I am more certain.

Now it may also be true that they are caused by brain processes, events. But that is a theory, which is another mental artifact, a conceptual construct. It is a very good theory, but the causal chain it postulates needs to be modified: brain process ---> mental event ---> physical action. Brain processes have a place in the causal chain, but (for willful, intentional actions) a conscious event intervenes. Yes, that conscious event is itself a product of a brain process. But it is the only phenomenon of which we have direct, immediate knowledge, and is the starting point of all inquires and theories (which are themselves conscious phenomena).

Theories of consciousness which endeavor to eliminate qualia and other mental phenomena entail a variant of Epimenides Paradox: not only do they eliminate the very phenomena they seek to explain, but themselves as well, since theories are themselves mental constructs.

[Gertie]

GE

To take the homunculous self observing the Cartesian 'experiential field' idea then.

Obviously we should expect to discover brain mechanisms which account for the structural ways human experience manifests - a unified, discrete, coherent field of consciousness with the ability to focus attention, correlated with a first person pov located in a specific body.

As I understand it, your suggestion is that a specific part of human brains is effectively an experiential model of the Self-as-Experiencer (homunculous), assessing the incoming sensory qualia, reasoning, checking memory, imagining scenarios/consequences, and such. And then making decisions and issuing commands to the motor systems. And this Experiencer-Self part of the brain mainifests experientially too.

Not quite (or perhaps this is only a terminological quibble). The "homunculus" (the subsystem which assesses the information represented in the model and initiates actions) is not per se represented in the model, and is not aware of itself as a brain subsystem. What it recognizes as "itself" is "that which is having these experiences," plus the representation of the organism as a whole in the model. (In other words, the brain system which apprehends the model is not aware of its own workings).

If that was the case, isn't that what we'd see on brain scans? Intense activity in this central control and command area whenever we are conscious, with a radial map of routes leading from sensory subsystems and to motor subsystems? Something like a wheel hub with spokes.

That would depend upon how that subsystem is distributed. The "homunculus" may not be localized in a particular brain area.

But that's not what scans find. If they had, that would be our understanding of how brains work.

Instead, scans find what experience feels like. Different subsystems dominating from moment to moment, as one or another gains attentional ascendance. Right now I'm concentrating on constructing this post, the corresponding part of my brain would be lighting up on a scan, while other subsystems which aren't the 'focus of my attention' right now would likely dim. Or if I'm listening to music I love my other subsystems take a breather, if I'm remembering something vividly, my current sensations fade, etc.

Inputs over the different sensory channels (vision, olfactory, tactile, etc.) deliver their signals to specific areas of the brain, for preliminary processing. Those areas will "light up" on scans when there is input over those channels. But as far as I know there is no "part of the brain" that corresponds to "concentrating on constructing this post." At best the scans can reveal that you're concentrating on something. But if you have a link to some work that indicates otherwise, please post.

Attention and focus on this or that subsystem seems to be how brains work, not everything is always present like a film being played in a Cartesian Theatre for the Self-Experiencer to take in and assess. The attention process happens automatically, unless I feel I 'intervene' and deliberately shift it.

Keep in mind that even at the Orpheum, your attention is directed to specific things/events on the screen from moment to moment. But the entire screen is always before you.

The reporting back issue has these experiential qualia being experientially observed by the Self-Experiencer, which still has to somehow report back to the physical brain systems, if the experience is a product of brains, rather than identical with brains. It's not a way out of that problem.

That is only a problem if you're imagining the homunculus to be something separate from the brain. But it isn't; it is intimately connected to it, but not identical with it.

Which brings us to over determinism. The 'experiential field' as a product of brain activity only avoids this problem if neural correlation doesn't hold surely. Is that your claim? That brain activity produces an 'experiential field' which then somehow escapes neural correlates? But somehow causes physical neural activity

Oh, no. Phenomenal experience is strongly correlated with brain states; the former only exists as long as the latter does. But correlation is not identity, and does not entail it.

The chief architect of the "Self-Model Theory of Subjectivity" is Thomas Metzinger (no, this theory was not invented by me!). His book, "Being No One, The Self-Model Theory of Subjectivity" is here (among many other places):

https://www.amazon.com/Being-No-One-Sel ... 0262633086

A precis by Metzinger is here:

https://citeseerx.ist.psu.edu/viewdoc/d ... 1&type=pdf

OK, here are the problems as I see them then.


As you agree neural correlation holds, then you're still stuck with the Hard Problem. Positing that experience is some kind of 'field' science can't account for, has no more explanatory value than positing it is some kind of 'perspective', or any other monist substance materialist 'What If'.


You're still stuck with addressing Over Determinism too, like all monist materialist positions. If neural correlation holds, and neurons are affected by physical causality just like any other physical stuff, then experiential states are redundant, and there would be no evolutionary pressure for them to arise. When in reality, they look honed for evolutionary utility.


You have an additional problem not just with explaining the generation of the 'experiential field', but with the way this field feeds back info/instructions to the physical brain systems.


If you're relying on neural correlation to explain that - see above. If alternatively you're relying on a Homunculus/Cartesian Theatre model to explain it, it just puts the problem a step. And we'd expect to be able to locate the homunculus brain system which activates any time a person is conscious, with neural connections centring there. We don't find that. We know there must be some mechanism whereby a sense of self-as-unified-observer/experiencer arises from the brain's inter-connected sub-systems, but it doesn't seem to be a homunculus/Cartesian Theatre type mechanism.


Testing - there is no way to test your preferred 'What If' against others.

[Faustus5]

Yes; Dennett et al would so claim.

Not just Dennett, but anyone committed to a non-dualist, non-supernatural model of consciousness, which you seemed to do when you earlier agreed that of course mental phenomena are just physical phenomena. Physical phenomena are only caused by other physical phenomena. There is no such thing as a mental event that is somehow physical but not a brain event.

But that claim is palpably false, as everyone who has ever had a thought, made a decision, formed an opinion, reached a judgment will confidently testify. I know without doubt, as did Descartes, that my actions are caused by acts of will (i.e., mental events). There is nothing of which I am more certain.

I think you are conflating two things that need to be kept very far apart from one another.

A. What everyone agrees exists and needs to be explained (mental phenomenon, subjective experience, whatever you want to call them). As you say, that these exist is something that no one can deny or wants to deny. Dennett, for instance, does not deny them and can only be characterized as having done so by deliberately ignoring his actual words.

B. One’s theoretical or ideological commitments to how the elements in A are best characterized and explained. One never establishes the reality of such commitments by claiming they cannot be denied. One establishes such commitments by making reasoned, evidence based arguments showing they are better than the alternatives.

It is a very good theory, but the causal chain it postulates needs to be modified: brain process ---> mental event ---> physical action. Brain processes have a place in the causal chain, but (for willful, intentional actions) a conscious event intervenes.

If mental events are physical events, which you earlier committed to, they can only be brain processes. There is literally no available alternative consistent with established cognitive neuroscience, which leads me to think I must be confused about what you are and are not trying to say.

Theories of consciousness which endeavor to eliminate qualia and other mental phenomena entail a variant of Epimenides Paradox. . .

Not even remotely, not by a zillion light years, is this statement true. Scientific theories are not logical theorems.