"Consciousness, Accessibility and the Mesh between Psychology and Neuroscience"
Neuphi
March 20, 2007, 4-6PM
Note-taker: J. T. , E. I
Last Updated: March 26, 2007
Preliminary Statement of the Puzzle
Cognitive accessibility vs. reportability
Are representations inside a Fodorian module phenomenal or not?
One suggestion: If a state is unreportable, it is not phenomenally conscious.
This doesn’t work because the ultimate data are themselves reports. Furthermore, we know that it is possible for unreportable states to be phenomenally conscious (Locked-in Syndrome).
The real question, then, is whether cognitively inaccessible states can be phenomenally conscious. In other words: is cognitive accessibility a part of phenomenal consciousness?
A real case
Binocular Rivalry – red/green alternating image. This seems explicable.
Fusiform face tests. Subject experiencing a face without being able to cognitively access that experience?
Can’t use induction, because we are interested in whether cognitive access is actually a part of what phenomenal consciousness is.
Medical importance
Terry Schiavo case, e.g. Whether or not the patient is having experiences would seem to be important for the decision of whether or not to pull the plug.
Importance for science of consciousness
Cognitive Accessibility
Using a Global Workspace Model of Cognitive Global Accessibility.
-Perceptual mechanisms are suppliers of representations.
-Mechanisms of reasoning, reporting, evaluating, deciding, etc, are “consumers”.
“Accessibility” is somewhat ambiguous here: could mean “in the global workspace” or “potentially in the global workspace”; the latter is too broad to be useful.
Correlationist methodology
Generally restricts discussions of consciousness to conscious access, since consciousness seems to be too difficult to cover in a broader sense.
Better methodology
Inference to the best explanation.
Empirical Argument
We have a sense of experiencing more than we can grasp cognitively.
Ex: Change blindness
But is this inattentional blindness or inattentional inaccessibility?
Thesis: it is blindness to change, but not blindness to the features that change.
Argument: Inattentional inaccessibility implies that there are different bases for phenomenal consciousness and attentive consciousness.
Refrigerator Light Illusion: subjects mistake the easy potential accessibility of all Sperling's letters with actual consciousness of them.
- Replies: but how can the way that it seems that it seems not actually be the way that it seems?
- Why wouldn’t this illusion vanish when we find out about it?
- No positive reason given for believing that the illusion exists—only the philosophical doctrine that access and consciousness must coincide.
What about the “illusion of seeing” noted in the change blindness discussion?
- Reply: The conclusions of these change blindness experiments are debatable.
Mesh Argument:
- Psychological argument: phenomenology overflows accessibility.
- If strong recurrent activations in the back of the head that are not globally broadcast are phenomenal (cf. discussions of V5 region), we have a neural mechanism for overflow.
- This is a reason for accepting that phenomenology doesn’t require global broadcasting.
In other words, abduction/inference to the best explanation (as in the Mesh Argument) dissolves the puzzle abstractly.
Q: Is it possible for phenomenology to be distinct from attention? Could cognitive access be distinct from attention?
A: Phenomenology can be distinct from attention. One recent article has a good argument that describes difference between phenomenology and attention. One of the dramatic cases involves attentional manipulation of blindsight patients. Subjects got faster with practice at the task of utilizing predicting/anti-predicting cues in their blind field. This suggests they can pay attention in the blind field, even without the phenomenology. So it looks like attention and phenomenology can be pretty separate. The relation between attention and cognitive accessibility is less clear. There is a recent study that shows that things (like faces) shown in the periphery can still be reported even if all the attention was soaked up in the center of the visual field. This seems to show that you can have access without attention, but it could also be that all the attention was not soaked up in the center of the field as the experimenters assumed.
Q: Can’t this V1-V5 recurrent processing loop simply be construed as a causal condition, along the lines of the necessity of the retina, or blood flow in the brain?
A: Some view that what the recurrent processing does is to amplify and refine the process, and that the activation itself (and not the recurrent process) is the real neural basis of phenomenology. I think this is a possibility, and that the experiments that have been done so far do not distinguish between the two possibilities. But I think that this is an issue that can be investigated; one might e.g. cut the connection between the fusiform face area and the lower area and stimulating the fusiform face area, to see whether you still get phenomenology (even with the absence of recurrent feedback).
Q: All of this discussion seemed to leave out any mention of memory, but memory might be an issue in any discussion of attention and experiments measuring attentiveness. When we talk about a subject experiencing phenomenology, shouldn’t there be a distinction regarding when a subject is recalling/remembering something as opposed to experiencing something right at that moment?
A: I did actually discuss memory, the global workspace I referred to is often referred to as working memory. Although long-term (permanent) memory probably affects phenomenology (e.g. tasting wine may utilize categories built into the long term memory system through previous experience), it is mostly likely not required for phenomenology. One of the conclusions of this paper is that phenomenology and working memory are importantly distinct, and that there is much more in phenomenology than in working memory.
Q: When I think about the difference between a computer/camera and a human brain, one difference seems to be that the former merely takes in energy, whereas a mind requires more than merely physical input—a comparative judgment of some sort, or a detection of difference, seems to be required. It doesn’t seem that there is consciousness in the former case. The V5 loop you mentioned might be getting closer to consciousness because it is informational…but it still seems we would need something like the frontal cortex or limbic system in order to have conscious experience.
A: Judgment is bringing some system of categories that you have in long term memory to apply to the current experience. I actually deny the premise that judgment is necessary for consciousness—I believe it is possible for an animal without long-term memory/concepts to still have conscious experience.
Q: Certain recognition processes are built into the brain, while others are learned. So when you speak of cognitive access, which sort of process do you have in mind?
A: You seem to be raising the issue, to what extent does the discussion of phenomenology of perception require the application of concepts? My view is that you can have experiences even when you’re not applying concepts (i.e. no activation of long term memory)—but you have a different experience when you do apply concepts from long term memory. Wine tasting is a great example of this. Concepts come in, but they’re not necessary.
Q: What is the difference between brain-state and neural account?
A: I don’t mean any distinction between those, they are used interchangeably.
Q: You had three accounts of the relationship between phenomenal consciousness and awareness: same order, higher order and automatic, and you think higher order is not necessary. I’m wondering, couldn’t either automatic or same order more congenial to your account? The same-order view is a version of a traditionally held Kantian categorical view which espouses that there is always not only awareness not just of color, but also awareness of “I’m seeing this color” (thus there must be Kantian categories). It seems that for you to espouse this view would make it sound like you’re building too much into it and hence would like to claim that the automatic view is more congenial.
A: I see your point. If I had to choose between automatic view, and the same-order-plus-Kant view, the same-order-plus-Kant structure fits more with my account. I would certainly agree with that.
Q: Some philosophers espouse that when I experience red, I also have to be aware that “I” am experiencing red. Your account doesn’t seem to be committed to that.
A: I may have some sympathy to that, although not talked about in this paper. There’s a paper referenced in my paper by Pollen that espouses the view that phenomenal consciousness must involve some parts of the brain related to the conception of the self. Kandisher’s (2001) paper writes that phenomenology requires binding in space and time (great echos to Kant). This is a place where neuroscience seems to be rediscovering some points that philosophers have been discussing for a long time.
Q: Mesh between psychology and neuroscience. You seem to try to establish some correspondence btw neural basis and the inner phenomenology of accessibility. The conclusion seems that if you have a certain neural basis then you have phenomenology. With a richer neural basis you can have phenomenology plus accessibility. So we can have a very mechanical scheme. Accessibility presumes phenomenology, i.e. that we have a richer neural basis. If some neural basis is taken away then you only have the phenomenology without accessibility. This seems to be the reduction of psychology to neural sciences. How do you account for the content of phenomenology within that reduction? You can locate some neural structure, neural phenomena, neural content of phenomenology. For example, how can we structurally account for the fact that although I see and recognize a lot of faces, but in with one face I have a special emotional attachment. I’m not sure about the idea that there is a 1-to-1 relation between such content and neural structure. Even the mesh idea seems too strong a structure.
A: You’re right that I am presupposing a reductionist point of view. However, it’s not exactly that I believe in such a view, but rather I am interested in how far you can push such a view, and what you can get out of this, and are there unanswerable questions (even in a reductionist point of view). My opponents are also reductionists, but think that there are unanswerable questions even on such a view. One thing that fits with your point: I’m not certain about is whether or not phenomenology is multiply realizable (on a machine for example). For now, I exclude these views. Re: 1-1 content-structure relatonship: The reductionist view that I’m presupposing is that consciousness itself (there being a conscious field) is identified with some kind of upper brain stem relation to the cortex (perhaps something like thalamal cortical oscillation). The specific contents, I’m identifying with specific activations within specific cortical systems (e.g. visual motion--recurrent loops between V5 and lower face areas; face experience--fusiform face area and lower area interaction). So I have corresponded phenomenal field with one and contents with another. I don’t know if this is precisely right, but it’s worth pushing it to see how far it can go.
Q: Consciousness here doesn’t seem like a natural kind, but there are reasons to think it ought to be.
A: You’re right in a sense, recurrent activation of V5 doesn’t seem rigid enough to be a natural kind, or perhaps too specific to human beings. One way to go about it might be to bring in multiple-realizability, but this would involve so many complexities. Thus for now, I choose to limit my investigation to human processes. I think that it would be premature at this stage of the inquiry to relax our assumptions about the reduction.
Q: What do you mean by cognitive accessibility does not "constitute" phenomenology?
A: I want the paper to be about the fact that cognitive accessibility is not included in phenomenology. What do I mean by that? It is not a part of it, in the standard sense. I claim that the machinery of phenomenology does not necessarily include the machinery going on in the front of the head (i.e., used in accessibility). My argument for this is the mesh argument.
Q: The quote from the authors in the paper who later retracted their view mentioned that their conclusion was logically flawed. Why did they say this?
A: Their point was that they just assumed the effect was the result of sparse representation, without considering other possibilities.
Q: One of your replies to the “refrigerator light illusion” was that it did not vanish when we found out about it…why is this a response to their argument?
A: Because it is a different type of illusion than standard perceptual illusions, it is a cognitive one, an illusion about how things seem. In general, with cognitive illusions (say, affirming the consequent or the gambler’s fallacy), once we learn about them, the illusion vanishes. In this case, the illusion doesn’t disappear when we learn about it.
Q: Let me ask about the slide discussing the relationship between perceptual awareness and brain-states (neural correlates). Since it’s the case that we’re not even reliable reporters of our own visual stimuli, how is it that we can ever make an equation between percepts and brain-states—it seems to be getting close to qualia.
A: If I understand you rightly, I agree with most of what you said. However, I think that it is possible for you to have experiences or perceptions that don’t make it all the way to the area of the brain involved in attentive consciousness. I’m arguing that there’s no bar for us understanding phenomenal consciousness physically.
Q: Classical phenomenology is very concerned with, e.g., figure-ground experimentation. What sorts of things are discussed in the phenomenology you’re after?
A: Many of the same issues come up; lots of work in this field is being done on figure-ground relationships.
Let me ask you a question now. I think the overlap between neuroscience and philosophy is very interesting, and I’m curious whether your department has any interest in starting a section of neuroscientific study, or giving credit for neuroscience classes, etc.?
A: Yes, there have been more and more students pursuing this area of study in the past ten years…where the students go, philosophy follows.
Reading: http://www.neuphi.com/images/readings/Block_BBS.pdf