Tag Archives: Crick

The New Unconsciousness

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claustrumDoctors at George Washington found by chance recently that stimulating a patient’s claustrum served to disrupt consciousness temporarily (abstract). The patient was being treated for epilepsy, and during this kind of surgery it is normal to use an electrode to stimulate areas of the brain in the target area before surgery to determine their role and help ensure the least possible damage is done to important functions. The claustrum is a sheet-like structure which seems to be well connected to many parts of the brain; Crick and Koch suggested it might be ‘the conductor of the orchestra’ of consciousness.

New Scientist reported this as the discovery of the ‘on/off’ switch for consciousness; but that really doesn’t seem to be the claustrum’s function: there’s no reason at the moment to suppose it is involved in falling asleep, or anaesthesia, or other kinds of unconsciousness, The on/off idea seems more like a relatively desperate attempt to explain the discovery in layman’s terms, reminiscent of the all-purpose generic tabloid newspaper technology report in Michael Frayn’s The Tin Men:

British scientists have developed a “magic box”, it was learned last night. The new wonder device was tested behind locked doors after years of research. Results were said to have exceeded expectations… …The device is switched on and off with a switch which works on the same principle as an ordinary domestic light switch…

Actually, one of the most interesting things about the finding is that the state the patient entered did not resemble sleep or any of those other states; she did not collapse or close her eyes, but instantly stopped reading and became unresponsive – although if she had been asked to perform a repetitive task before stimulation started, she would continue for a few seconds before tailing off. On some occasions she uttered a few incoherent syllables unprompted. This does sound more novel and potentially more interesting than a mere on/off switch. She was unable to report what the experience was like as she had no memory of it afterwards – that squares with the idea that consciousness was entirely absent during stimulation, though it’s fair to note that part of her hippocampus, which has an important role in memory formation, had already been removed.

Could Crick and Koch now be vindicated? It seems likely in part: the claustrum seems at least to have some important role – but it’s not absolutely clear that it is a co-ordinating one. One of the long-running problems for consciousness has been the binding problem: how the different sensory inputs, processed and delivered at different speeds, somehow come together into a smoothly co-ordinated experience. It could be that the claustrum helps with this, though some further explanation would be needed. As a long shot, it might even be that the claustrum is part of the ‘Global Workspace’ of the mind hypothesised by Bernard Baars, an idea that is still regularly invoked and quoted.

But we must be cautious. All we really know is that stimulating the claustrum disrupted consciousness. That does not mean consciousness happens in the claustrum. If you blow up a major road junction near a car factory, production may cease, but it doesn’t mean that the junction was where the cars were manufactured. Looking at it sceptically we might note that since the claustrum is well connected it might provide an effective way of zapping several important areas at once, and it might be the function of one or more of these other areas that is essential to sustaining consciousness.

However, it is surely noteworthy that a new way of being unconscious should have been discovered. It seems an unprecedentedly pure way, with a very narrow focus on high level activity, and that does suggest that we’re close to key functions. It is ethically impossible to put electrodes in anyone’s claustrum for mere research reasons, so the study cannot be directly replicated or followed up; but perhaps the advance of technology will provide another way.

Structural Qualia

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structureKristjan Loorits says he has a solution to the Hard Problem, and it’s all about structure.

His framing of the problem is that it’s about the incompatibility of three plausible theses:

  1. all the objects of physics and other natural sciences can be fully analyzed in terms of structure and relations, or simply, in structural terms.
  2. consciousness is (or has) something over and above its structure and relations.
  3. the existence and nature of consciousness can be explained in terms of natural sciences.

At first sight it may look a bit odd to make structure so central. In effect Loorits claims that the distinguishing character of entities within science is structure, while qualia are monadic – single, unanalysable, unconnected. He says that he cannot think of anything within physics that lacks structure in this way – and if anyone could come up with such a thing it would surely be regarded as another item in the peculiar world of qualia rather than something within ordinary physics.

Loorits approach has the merit of keeping things at the most general level possible, so that it works for any future perfected science as well as the unfinished version we know at the moment. I’m not sure he is right to see qualia as necessarily monadic, though. One of th best known arguments for the existence of qualia is the inverted spectrum. If all the colours were swapped for their opposites within one person’s brain – green for red, and so on – how could we ever tell? The swappee would still refer to the sky as blue, in spite of experiencing what the rest of us would call orange. Yet we cannot – can we? – say that there is no difference between the experience of blue and the experience of orange.

Now when people make that argument, going right back to Locke, they normally chose inversion because that preserves all the relationships between colours.  Adding or subtracting colours produce results which are inverted for the swappee, but consistently. There is a feeling that the argument would not work if we merely took out cerulean from the spectrum and put in puce instead, because then the spectrum would look odd to the swappee.  We most certainly could not remove the quale of green and replace it with the quale of cherry flavour or the quale of distant trumpets; such substitutions would be obvious and worrying (or so people seem to think). If that’s all true then it seems qualia do have structural relationships: they sort of borrow those of their objective counterparts.  Quite how or why that should be is an interesting issue in itself, but at any rate it looks doubtful whether we can safely claim that qualia are monadic.

Nevertheless, I think Loorits’ set-up is basically reasonable: in a way he is echoing the view that mental content lacks physical location and extension, an opinion that goes back to Descartes and was more recently presented in a slightly different form by McGinn.

For his actual theory he rests on the views of Crick and Koch, though he is not necessarily committed to them. The mysterious privacy of qualia, in his view, amounts to our having information about our mental states which we cannot communicate. When we see a red rose, the experience is constituted by the activity of a bunch of neurons. But in addition, a lot of other connected neurons raise their level of activity: not enough to pass the threshold for entering into consciousness, but enough to have some effect. It is this penumbra of subliminal neural activity that constitutes the inexpressible qualia. Since this activity is below the level of consciousness it cannot be reported and has no explicit causal effects on our behaviour; but it can affect our attitudes and emotions in less visible ways.

It therefore turns out that qualia re indeed not monadic after all; they do have structure and relations, just not ones that are visible to us.

Interestingly, Loorits goes on to propose an empirical test. He mentions an example quoted by Dennett: a chord on the guitar sound like a single thing, but when we hear the three notes played separately first, we become able to ‘hear’ them separately within the chord. On Loorits’ view, part of what happens here is that hearing the notes separately boosts some of the neuronal activity which was originally subliminal so that we become aware of it: when we go back to the chord we’re now aware of a little more information about why it sounds as it does, and the qualic mystery of the original chord is actually slightly diminished.

Couldn’t there be a future machine that elucidated qualia in this way but more effectively, asks Loorits?  Such a machine would scan our brain while we were looking at the rose and note the groups of neurons whose activity increased only to subliminal levels. Then it could directly stimulate each of these areas to tip them over the limit into consciousness. For us the invisible experiences that made up our red quale would be played back into our consciousness, and when we had been through them we should finally understand why the red quale was what it was: we should know what seeing red was like and be able for the first time to describe it effectively.

Fascinating idea, but I can’t imagine what it would be like; and there’s the rub, perhaps. I think a true qualophile would say, yes, all very well, but once we’ve got your complete understanding of the red experience, there’s still going to be something over and above it all; the qualia will still somehow escape.

The truth is that Loorits’ theory is not really an explanation of qualia: it’s a sceptical explanation of why we think we have qualia. This becomes clear, if it wasn’t already, when he reviews the philosophical arguments: he doesn’t, for example, think philosophical zombies, people exactly like us but without qualia, are actually possible.

That is a perfectly respectable point of view, with a great deal to be said for it. If we are sceptics,  Loorits’ theory provides an exceptionally clear and sensible underpinning for our disbelief; it might even turn out to be testable. But I don’t think it will end the argument.

 

The Cambridge Declaration

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At the Francis Crick Memorial Conference back in July the participants signed a Declaration (pdf) affirming that animals are conscious. The key passage reads:

“The absence of a neocortex does not appear to preclude an organism from experiencing affective states. Convergent evidence indicates that non-human animals have the neuroanatomical, neurochemical, and neurophysiological substrates of conscious states along with the capacity to exhibit intentional behaviors. Consequently, the weight of evidence indicates that humans are not unique in possessing the neurological substrates that generate consciousness. Nonhuman animals, including all mammals and birds, and many other creatures, including octopuses, also possess these neurological substrates.”

Actually, you’ll notice that that paragraph crams on the brakes an inch short of saying that animals are conscious. It says they have various substrates and that it doesn’t seem to be impossible that they should have ‘affective states’. More boldly it says they have the capacity to exhibit intentional behaviours.

We could certainly do with some clarity on this issue – but why are scientists issuing a Declaration? Don’t they just publish papers and leave the results to speak for themselves? There’s a clear intention that the Declaration should have political impact, at least encouraging protection of animals, perhaps lending support to the idea of animal rights, possibly even giving a boost to veganism if we assume Philip Low (Portuguese text) was serious. (In fact I suppose we might have to go further and intervene to prevent carnivores of other species pursuing their traditional diet.)

Whatever we feel about that, it takes us into contentious territory, and I think there are in any case two other factors which make discussion in this area especially complicated. One is that there is a hidden dispute here about standards of proof. At least three standards are, as it were, in play. There’s the ordinary/political standard of proof, which requires something to be shown to be true clearly enough that we believe it and generally expect others to believe it. There’s the scientific standard of proof, which requires more rigorous evidence, reproducibility of results, and endorsement by peer review. Then there’s the philosophical standard of proof, which requires that no rational being who understands the case could possibly think otherwise, which actually makes it tough to prove that animals even exist, never mind what their mental states are. All of these different standards have their place, but discussion of animal consciousness is handicapped by differences and misunderstandings about which to invoke in which contexts.

Animal consciousness is also a peculiarly emotive subject. Our conclusions may be very strongly affected by feelings of empathy, and indeed there is an argument that empathy is an appropriate response.  Although I’ve never heard this particular argument made explicitly, it can be argued legitimately that even if animals are not conscious, we are better people if we let our empathy cause us to believe they are, because empathy is such a vital human quality it even trumps strict truth in this case. It’s better to waste some sympathy on creatures that don’t really deserve it than risk remaining cold to those that do, in other words. At any rate some may feel that those who deny that animals have feelings at all (step forward, Descartes) are deficient in perception or even perhaps in moral sense, a feeling that sceptics on their side are not apt to welcome.

So discussion is potentially difficult, and so it is with all due caution I say I think the Declaration is probably a bad idea overall; and that there are three particular problems with it.

The first problem is that it doesn’t seem well-motivated scientifically, by which I mean it doesn’t seem to be inspired by any definite scientific result. The preliminary passages of the Declaration do allude to various pieces of research, but the basic case is that animals have much of the same brain hardware as human beings, and also exhibit the right sorts of behaviour. We’ve known that for a long time. If some scientific Rubicon has been crossed recently, I missed it and I can’t see it set out here. To make matters worse the Declaration seems to come close to a clunking logical error, along the lines of: other areas than the neocortex are involved in having feelings; animals have those other areas, therefore animals have feelings. That wouldn’t work: you could as well argue that: other organs than the eye are involved in seeing; people whose eyes have been gouged out have those other organs; therefore people whose eyes have been gouged out can see. You can’t really dismiss the neocortex that easily.

The second problem is that we’re not told clearly which animals are conscious, and no allowance is made for different levels of consciousness in different species. On the face of it it seems the claim is that insects are just as conscious as anyone else (so those classic observations of stereotyped behaviour in sphex wasps must somehow have been wrong). In fact Christof Koch seems to be saying everything is conscious. That’s too extreme to be plausible and too vague to be helpful, especially in a context where we’re implicitly thinking about political rights and moral status. This is by no means an academic problem in a world where, for one thing, experimental animals may be sacrificed to help save human lives; if we think all beings have an equal share of consciousness there will certainly be no more animal experiments, and if we get it wrong either way that has serious consequences.

The third problem is that we’re not told what kind of consciousness. The Declaration seems mainly to be about whether animals feel pain, but it makes no distinction between a capacity for suffering and a capacity for rational planning (or indeed self-awareness). These are radically different things, and we might well find it much more likely that animals have the former than the latter.

This is important in two respects. First, if animals have feelings, then we might want to enact laws protecting them from pain; but we won’t feel inclined to give them rights unless we think they have the kind of intentional thought that would allow them to exercise those rights. To have legal rights you need to be the kind of entity that might go to court to enforce them, and presumably the kind of entity which also has duties and gets punished for infractions.  Actually, that’s not quite true; we might still want to give animals the special kind of rights that children or comatose patients have, which need to be exercised on their behalf by others and entail no obligations; but even if we do that it’s important to keep track of what legal/moral status we’re actually awarding.

Second, the presence or absence of rational conscious thought might affect our view of how important feelings are. It might be that some animals can indeed feel pain in a basic way, but that without human-style neocortex-driven awareness their pains are only like dream ones, or like pains we instantly forget (some people take the view that a forgotten agony doesn’t matter; and indeed surgeons use mnestics, which make you forget the pain, almost interchangeably with true anaesthetics, which actually stop you feeling it in the first place). Even if animals feel pain it might still be that their pains are of lesser value or even of no account at all; and the presence or absence of explicitly entertained thoughts, projects and desires might be relevant.

There’s an awful lot more to be said about these issues, quite a lot of it on the Declaration’s side, but that brings me to the overall problem. What is the Declaration for, and what will it be used for? I presume the aspiration is that it will be cited wherever the treatment of animals is an issue. Its function is surely meant to be to give clarity, but to do it by curtailing argument; to end discussion. That’s certainly liable to be the way it is used, at any rate. I don’t like that at all; there are cases where it’s legitimate to try to close down an area of discussion, but I don’t think this is one; the attempt is at best radically premature, at worst profoundly unhelpful. If anything we should be promoting discussion. Wouldn’t it have been better, and more appropriate to Crick’s memory, if the participants in the Conference had, in that spirit, published a list of good questions?