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Author
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Topic: New Issue of PCID: Volume 2.3, Philosophy of Mind
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Rex Kerr
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Member # 632
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posted 04. December 2003 04:14
I'm still waiting for a single datapoint where all reductionistic factors are thought to be known, and yet behavior cannot be accounted for (at least to within a statistical distribution, as in QM).
There are cases where we can causally specify the connection between brain structure and mental phenomena. There are cases where we have mental phenomena and don't know how it relates to different brain structures (formally leaving open the possibility that it doesn't relate). However, there are no cases where we know that brain structures/activity are identical, and yet two different mental phenomena result.
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Micah Sparacio
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posted 04. December 2003 07:51
quote:
Micah, can you give an example of a phenomena that you think might "have no physical correlation nor ...causal specificity" with the brain?
And, if there is such a phenomena, doesn't that mean that at least in regards to that phenomena there is a "disembodied" aspect of mind?
Evan, I'll be honest. I don't think we're talking on the same level, so I'll try to do my best, but I'm worried that we're going to start talking in circles. Not a criticism of you, by any means... this happens all the time when talking about things that are at the edge of our epistemological grasp...
The clearest example I can give, and the most widely used example, is the nature of "raw experience." Experience is dependent on a brain. Experience can be modified or even destroyed by taking drugs. Yet the mental aspect of experience is not like anything we have in our physical theories.
What can our physical theories tell us? Well, imagine I've just been stabbed with a knife. Ok, so our physical theories can tell us things at many levels, but let's just focus on the crudest meta-level for simplicity's sake. A sharp metal object moves through space and punctures my skin. Lots and lots of my skin, blood, etc moves around. Electrical currents move through my neural system, up my spinal cord, and to my brain. There is more movement in my brain, probably localized, but not necessarily. Movement, movement, movement, more movement. That is what physical theories tell us - things move here and there for various reasons. Push-pull mechanics.
And yet, after all the pushing and pulling, all the physiological movement, you've given me ABSOLUTELY NO REASON why this should result in the rich phenomenal sensation that we call "pain."
When I use the word "causal specificity" what I want is more than correlation. I want to know *how* the rich, sensational nature of experience is related to the pushing and pulling (and neural firing) that happens in the brain. (I use neural firing as a place holder for whatever physical mechanisms are happening in the brain - the Penrose-Hameroff model argues that the on-off switch model of the brain is wrong and so they appeal to activity in the microtubules as an argument for quantum minds).
In any case, that's enough huffing and puffing. I've found that some people "get it" and some people don't (and it very well may be that the people who "get it" are wrong).
But to me, there seems to be a *fundamental divide* between what we know about the physical world and what we know about the phenomenal/experiential/sensational aspects of consciousness. Not that they aren't related. It's just that we're missing something fundamental about the world when we do the following:
A reduction:
I see red -> a certain configuration of neurons fired in my brain
There's something rich and important to us about the sensation that we totally lose in all current physical reductions.
Just so that you know...my best, naive guess is that the mind is going to turn out to be some sort of "field" that obeys certain "mental" laws and will thus potentially be accessible to science. But that is just a wild guess. I see no reason to believe that the mind is not part of nature. I see lots of reasons to think that nature is quite a bit bigger than our current physical theories allow for.
[ 04. December 2003, 08:01: Message edited by: Micah Sparacio ]
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Micah Sparacio
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posted 04. December 2003 08:12
In response to Rex, I'll quote a portion of my post above:
quote:
When I use the word "causal specificity" what I want is more than correlation. I want to know *how* the rich, sensational nature of experience is related to the pushing and pulling (and neural firing) that happens in the brain. (I use neural firing as a place holder for whatever physical mechanisms are happening in the brain - the Penrose-Hameroff model argues that the on-off switch model of the brain is wrong and so they appeal to activity in the microtubules as an argument for quantum minds).
Why should we expect sensation to come from physical movement?
quote:
There are cases where we can causally specify the connection between brain structure and mental phenomena.
No doubt. About two times a month I go over to the fMRI labs at Princeton University to have my brain scanned for the purpose of helping science discover these connections. I'm particularly interested in visual cortex experiments (because visual experience is so rich), and spend the majority of my time scanning on these experiments.
Still, if nothing else, these experiments and their results confirm my intuition: for all the mappable activity taking place in my visual cortex, I still haven't a clue why my visual sensations exist. There is a gap between visual cortex activity and the "raw visual experience" of seeing Bart skateboard down a street in Springfield (though most of the time I'm watching black and white checkerboard's flash on the screen or tracking green and orange bars that circle around my visual field).
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Evan
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Member # 164
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posted 04. December 2003 08:24
Micah writes,
quote:
Evan, I'll be honest. I don't think we're talking on the same level, so I'll try to do my best, but I'm worried that we're going to start talking in circles. Not a criticism of you, by any means... this happens all the time when talking about things that are at the edge of our epistemological grasp..
I’m not sure why you think we’re not talking on same level - I think I understand quite well that there is a mystery of consciousness. If you refer back to my earlier post at the start of this thread, I discussed the question of trying to grasp the nature of consciousness itself separate from any content to that consciousness, which is one of the spiritual goals of the Eastern religions.
So you write
quote:
When I use the word "causal specificity" what I want is more than correlation. I want to know *how* the rich, sensational nature of experience is related to the pushing and pulling (and neural firing) that happens in the brain. ...
But to me, there seems to be a *fundamental divide* between what we know about the physical world and what we know about the phenomenal/experiential/sensational aspects of consciousness. Not that they aren't related. It's just that we're missing something fundamental about the world ...
I share an interest in these questions and I think I “get” the issue you are trying to address. I hope we can continue the discussion.
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Joy Busey
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Member # 610
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posted 04. December 2003 11:38
quote:
Micah Sparacio said: No doubt. About two times a month I go over to the fMRI labs at Princeton University to have my brain scanned for the purpose of helping science discover these connections. I'm particularly interested in visual cortex experiments (because visual experience is so rich), and spend the majority of my time scanning on these experiments.
Greetings, Micah. I have watched this thread since it arrived, and am pleased to see some meaty discussion. There may be very little I can add, but I've been involved in the "Consciousness quest" for a number of years. Completed the UA course (Chalmers, Hameroff, Scott, Klein, Stapp, et. al.] in 2000, and am contributing on a continuing basis to research on anomalous presentations - in particular, synesthetic perceptions. These have relevance to questions about whether "Mind" is emergent from physical constructs and processes (a "bottom-up" causal situation), or is a supervenient property suggesting "top-down" causation.
quote:
Still, if nothing else, these experiments and their results confirm my intuition: for all the mappable activity taking place in my visual cortex, I still haven't a clue why my visual sensations exist. There is a gap between visual cortex activity and the "raw visual experience" of seeing Bart skateboard down a street in Springfield (though most of the time I'm watching black and white checkerboard's flash on the screen or tracking green and orange bars that circle around my visual field).
Conversely, the sensory qualia of a synesthete are quite different from those of "regular" people. The anomaly has been recognized for a couple of centuries at least, though serious investigation has had to await technologies that can assess physical brain activity in real time. Consequently many of the incomplete studies of the past - dealing with less than a handful of self-identified synesthetes - have been so limited as to lead to erroneous conclusions about the anomaly that have gained the status of scientific "urban legend" and have little to do with the commonality or nature of the "condition."
Anyway, it seems pertinent at this point in the discussion that someone mention the fact that there is an essentially dualistic dynamic present in the expressions, attributes and self-perceptions of consciousness even though these things correlate to certain activities in the brain. Perhaps best described as a "self" that can - and often does - specifically direct brain processes, attention, awareness, perception and global entanglement to its own intent. This tends to throw a monkey wrench into the physicalist notion that attention, awareness, sensation and global entanglement are effects caused by brain processes. My position is that things are in reality quite the other way around.
Until the recent multidisciplinary investigation was formally launched - in large part initiated and funded by AI researchers - much of the research into brain states (phenomena of consciousness) took place in the quasi-scientific realm of psychology. Anomalous presentations came to be recognized by psychologists because the people exhibiting the anomalies sometimes came to psychologists for help. IOW, they suffered from pathological difficulties in coping.
This of course skews the data and easily leads to erroneous conclusions. Those get published in the literature and generally accepted as accurate even though the bias is obvious. Very recently researchers have become aware of the research bias through their participation in the wider consciousness investigations, where they've been introduced to people with anomalous perceptual abilities who don't have any trouble coping with life in the world, so don't end up in the shrink's office seeking help. There is even a website now for gathering data from self-identified synesthetes, and already the demographics are falsifying past studies.
Before I begin to list some of the things I know about this particular anomaly, there is a point to be made in general about psychological studies and why they are so often dismissed by cognitive scientists and others working with physical brain functions. This has to do with the tendency of scientists (and until recently, psychologists) to discount first-person accounts. For instance, I could report a particular synesthetic perception and describe how it "feels" to me, and how I am able to consciously control and integrate the information into a global state for my own purposes of "knowing" what those perceptions are telling me about the environment.
A biased researcher will tend to brush aside as meaningless anything I say that does not correlate with whatever preconceived notions he/she has about the "condition" I "suffer," and report their own opinions in support of their own hypothesis. I have been reduced to nothing more than a semi-interesting set of factoids that may or may not be useful to their hypothesis. If not, I am further reduced to mere counterfactual that can safely be ignored.
I have found that this situation of researcher bias exists in a number of fields that have yet to fully accept the multidisciplinary approach to what is being quantified - consciousness. Everyone has their own ideas and their own philosophical ideologies about those ideas. I personally think this is the wrong way to go about an empirical investigation, but have been lucky enough to encounter a few genuinely curious and impartial scientists. There is much to learn.
It's all very fascinating to me, and it's about time science began to take the phenomenon of consciousness seriously. I commend PCID for jumping into the fray!
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Rex Kerr
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posted 04. December 2003 16:39
I don't think there are a priori reasons to expect sensation from physical movement. But ion channels change structure, sodium ions flow through, etc. etc., and physical movement causes neuronal firing.
I don't think there are a priori reasons to expect sensation from neuronal firing. Yet when we shock a nerve, we feel something. If the nerve is severed, we go numb. So, oddly enough, the physical movement that causes neuronal firing is essential for perception. Is it possible to come to philosophical and conceptual peace with this fact? Is there a reason to believe that consciousness is any different?
I think fMRI studies are fascinating, but I wouldn't place too much faith in what they can accomplish. We know that the action of the brain is a the neuronal level on the timescale of milliseconds, but fMRIs gather information from regions a thousand times too big, a thousand times too slow. Thus, fMRI lends itself to primarily phenomenologial descriptions, without making a connection to an alternate level of description. That is, fMRI can be used to link behavior and large-scale brain activity, but it won't get all the way to the pushing and pulling that Micah is worried about because it can't see that scale.
Since fMRI is not a tool that has the resolution to make that connection, unless we were accidentally very lucky, I am not surprised that Micah doesn't see the connections in the experiments he attends. Nonetheless, I encourage him to continue participating in the experiments...there are lots of other things to learn about the brain aside from whether and how mechanistic consciousness is implemented!
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Mark Szlazak
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Member # 391
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posted 04. December 2003 20:29
Rex states the challenge that physiological data poses to substance dualism but it isn't as great as it first seems.
McTaggart argued that materialists make various unwarrented inferential leaps when they interpret the evidence. No matter how intimate the mind-body connection seems to be, the data don't establish limits on the possible manifestations of selfhood. The physiological evidence doesn't show that self or consciousness is exclusively linked to bodily processes, much less the process of any particular physical body. McTaggart argued
quote:
it does not follow, because a self which has a body cannot get its data except in connexion with that body, that it would be impossible for a self without a body to get data in some other way. It may be just the existence of the body which makes these other ways impossible at present. If a man is shut up in a house, the transparency of the windows is an essential condition of his seeing the sky. But it would not be prudent to infer that, if he walked out of the house, he could not see the sky because there was no longer any glass through which he might see it.
McTaggart makes a similar point between brain states and mental states.
quote:
Even if the brain is essential to thought while we have bodies, it would not follow that when we ceased to have brains we could not think without them ... It might be that the present inability of the self to think except in connexion with the body was a limitation which was imposed by the presence of the body, and which vanished with it.
Also, because of the prima facia evidence for it, this position is even more compelling.
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Rex Kerr
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posted 04. December 2003 21:53
McTaggart is logically correct in the quoted passages. However, he relies upon concepts such as "a self without a body" that are essentially without evidence (unless you count popular opinion).
One could also introduce concepts like electrointelligence, where thought and self was material, but electrical only, and governed by yet-undiscovered physical laws, and was hampered and captured by interactions with the physical body; it would then, perhaps, make sense to try to free the our true abilities as conscious entities by flash-incinerating ourselves.
Scientifically, I think the appropriate approach is to reject all such evidence-free schemes, popular or no; and likewise, to reject the "you'll never find it" argument unless we have looked, and self/mind/consciousness is not there.
Making such a determination now reminds me of asking a six-year-old to look for a book in the library, whereupon he glances in the door, turns around, and proclaims, "I looked, they don't have it."
The amount of looking one must do to be convinced of the absence of something is a function of how complex the place is that one is looking. The brain is a very, very complicated place indeed, considering only material aspects.
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jasonyoung
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posted 04. December 2003 22:31
quote:
When I use the word "causal specificity" what I want is more than correlation
I hate to point out the obvious, but science currently lacks the logical equipment needed to make such a connection.
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Mark Szlazak
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posted 04. December 2003 23:10
Rex: quote:
McTaggart is logically correct in the quoted passages. However, he relies upon concepts such as "a self without a body" that are essentially without evidence (unless you count popular opinion).
I'm not just talking about popular opinion and it's not as evidence free as some professional debunkers think (not referring to you Rex). Everyone, it's a bit of an investment but please have a look: Immortal Remains
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RBH
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posted 07. December 2003 20:19
Apropos of the relation between brain and consciousness, this paper (requires subscription). The basic finding is that parietal cortex is somehow involved in our awareness of the intention to act. Essentially, people with parietal damage are not able to report an intention to act until the action occurs.
Carl Zimmer summarizes and discusses the research more succinctly than I could: quote:
[Describing Libet's 20-year old seminal study] Near the top of the brain there's a region known as the motor area where neurons fire to make the body move in particular ways. Libet found that EEG recordings from the motor area in his subjects' brains began to shift into a new pattern 1.5 seconds before the subjects pressed the button. Libet interpreted this as the mental preparation that goes into initiating an action. But his subjects consistently claimed that they began thinking about moving their hand about half a second after the EEG recordings began to change. In other words, they had already started preparing to make a voluntary movement for half a second before they felt like they were making a voluntary movement.
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[Recently, a European research group] ...ran Libet's experiment again, but some of the people they chose as their subjects had damage to certain parts of the brain. As they report in Nature Neuroscience, some kinds of brain damage make no difference to people's performance. But something fascinating happened to people who suffered damage to the parietal cortex, located at the back of the head. Like the healthy controls, they could nail the moment they actually pressed the button, to within a few milliseconds. But they also noted that they intended to press the button just around the time they actually did press the button. In other words, they were completely unconscious of their action until the action was already taking place.
Clearly "conscious" here means "awareness." That is inconsistent with Micah's philosophical conception of consciousness: quote:
I'd just like to point out that while "consciousness" may have a heavy connotational load, it does have a fairly precise meaning to those who are working on the problem in contemporary philosophy. It means nothing more than "raw experience." It typically does not mean what RBH indicates -> awareness (unless specified as such).
Since we know that processing of sensory information begins far out at the periphery, I'm less than entranced with the notion of "raw experience." Our experience is heavily processed from the get-go, and the only place "raw" experience can be said to exist in the visual system, for example, is at the surface of the cornea. I still remember (with a faint sheen of sweat on my brow) the first question I was asked in my preliminary doctoral oral examination: "O.K., R, start with the cornea and take color perception as far into the central nervous system as you can." It took me 10 minutes to just get out of the retina and into the thalamus. I have trouble even imagining what "raw experience" might mean in any operational or neurological sense. It strikes me as one of those notions that are interesting to talk about after a few beers in grad school, but that have no useful correspondence with reality. Talking about a fictional notion - "raw experience" - doesn't strike me as a potentially fruitful way to proceed to an understanding of how reality operates.
RBH
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Micah Sparacio
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posted 08. December 2003 08:44
Jason Young says:
"I hate to point out the obvious, but science currently lacks the logical equipment needed to make such a connection."
What he's referring to here is a quote that I made regarding my desire to see more than correlation -> causal specficity.
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But Jason, you're critiquing me out context as far as I can tell (some sort of Humean critique on the nature of causation). Here's what I meant:
Science can tell us that when it gets cold, water freezes. That's correlation. But it can also tell us the reasons that water freezes when it gets cold. That's causal specificity.
Anyone can notice that conscioussness is associated with the brain. But as for explaining the reasons, why physical motion in the brain causes phenomenal experience, we've not a clue.
quote:
Both third-person data and first-person data need explanation. An example is given by the case of musical processing. If we observe a subject listening to music, relevant third-person data include those concerning the nature of the auditory stimulus, its effects on the ear and the auditory cortex of the subject, various behavioral responses by the subject, and any verbal reports the subject might produce. All of these third-person data need explanation, but they are not all that needs explanation. As anyone who has listened to music knows, there is also a distinctive quality of subjective experience associated with listening to music. A science of music that explained the various third-person data listed above, but that did not explain the first-person data of musical experience, would be a seriously incomplete science of music. A complete science of musical experience must explain both sorts of phenomena, preferably within an integrated framework.
The problems of explaining third-person data associated with consciousness are sometimes called the "easy problems" of consciousness. The problem of explaining first-person data associated with consciousness is sometimes called the "hard problem" of consciousness. This is not because the problems associated with third-person data are in any sense trivial, but rather is because we have a clear model for how we might go about explaining them.
How Can We Construct a Science of Consciousness?
[ 08. December 2003, 08:45: Message edited by: Micah Sparacio ]
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Rex Kerr
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posted 08. December 2003 17:50
I still don't understand why the first person problem is any harder than the third person problem.
If you have a sensory processing loop that functions at a high level of abstraction and contains abstract representations of itself, self-consciousness of some sort seems almost impossible to avoid. What is the distinction between this advanced cognitive processor processing happy-thoughts, and consciousness of happiness?
Added in edit, after reading Chalmers' article: In other words, why don't you believe Chalmers' fairly optimistic account in the paper you linked to? (Or do you agree with his assessment?)
[ 08. December 2003, 18:01: Message edited by: Rex Kerr ]
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Micah Sparacio
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posted 09. December 2003 09:34
Rex,
I DO agree with Chalmers "fairly optimistic" assessment. But, I think his optimistic assessment requires, as he notes, new methodologies - new approaches.
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Rex Kerr
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posted 09. December 2003 12:44
Fair enough. But Chalmers outlines the "new approaches", which are basically the same old approaches we always use--match up the third-person data with first-person data, and once it reaches a certain level of reliability, begin to equate the third- and first-person data as different ways of looking at the same thing, assuming that is even vaguely plausible.
In other words, Chalmers' new(?) approach seems to be "keep doing what we're already doing". Unless I missed something when I looked through his article.
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