Posts tagged ‘Graziano’

Where did consciousness come from? A recent piece in New Scientist (paywalled, I’m afraid) reviewed a number of ideas about the evolutionary origin and biological nature of consciousness. The article obligingly offered a set of ten criteria for judging whether an organism is conscious or not…

  • Recognises itself in a mirror
  • Has insight into the minds of others
  • Displays regret having made a bad decision
  • Heart races in stressful situations
  • Has many dopamine receptors in its brain to sense reward
  • Highly flexible in making decisions
  • Has ability to focus attention (subjective experience)
  • Needs to sleep
  • Sensitive to anaesthetics
  • Displays unlimited associative learning

This is clearly a bit of a mixed bag. One or two of these have a clear theoretical base; they could be used as the basis of a plausible definition of consciousness. Having insight into the minds of others (‘theory of mind’) is one, and unlimited associative learning looks like another. But robots and aliens need not have dopamine receptors or racing hearts, yet we surely wouldn’t rule out their being conscious on that account. The list is less like notes towards a definition and more of a collection of symptoms.

They’re drawn from some quite different sources, too. The idea that self-awareness and awareness of the minds of others has something to do with consciousness is widely accepted and the piece alludes to some examples in animals. A chimp shown a mirror will touch a spot that had been covertly placed on its forehead, which is (debatably) said to prove it knows that the reflection is itself. A scrub jay will re-hide food if it was seen doing the hiding the first time – unless it was seen only by its own mate. A rat that pressed the wrong lever in an experiment will, it seems, gaze regretfully at the right one (‘What do you do for a living?’ ‘Oh, I assess the level of regret in a rat’s gaze.’) Self-awareness certainly could constitute consciousness if higher-order theories are right, but to me it looks more like a product of consciousness and hence a symptom, albeit a pretty good one.

Another possibility is hedonic variation, here championed by Jesse Prinz and Bjørn Grinde. Many animals exhibit a raised heart rate and dopamine levels when stimulated – but not amphibians or fish (who seem to be getting a bad press on the consciousness front lately). There’s a definite theoretical insight underlying this one. The idea is that assigning pleasure to some outcomes and letting that drive behaviour instead of just running off fixed patterns instinctively, allows an extra degree of flexibility which on the whole has a positive survival value. Grinde apparently thinks there are downsides too and on that account it’s unlikely that consciousness evolved more than once. The basic idea here seems to make a lot of sense, but the dopamine stuff apparently requires us to think that lizards are conscious while newts are not. That seems a fine distinction, though I have to admit that I don’t have enough experience of newts to make the judgement (or of lizards either if I’m being completely honest).

Bruno van Swinderen has a different view, relating consciousness to subjective experience. That, of course, is notoriously unmeasurable according to many, but luckily van Swinderen thinks it correlates with selective attention, or indeed is much the same thing. Why on earth he thinks that remains obscure, but he measures selective attention with some exquisitely designed equipment plugged into the brains of fruit flies. (‘Oh, you do rat regret? I measure how attentively flies are watching things.’)

Sleep might be a handy indicator, as van Swinderen believes it is creatures that do selective attention that need it. They also, from insects to vertebrates (fish are in this time), need comparable doses of anaesthetic to knock them out, whereas nematode worms need far more to stop them in their tracks. I don’t know whether this is enough. I think if I were shown a nematode that had finally been drugged up enough to make it keep still, I might be prepared to say it was unconscious; and if something can become unconscious, it must previously have been conscious.

Some think by contrast that we need a narrower view; Michael Graziano reckons you need a mental model, and while fish are still in, he would exclude the insects and crustaceans van Swinderen grants consciousness to. Eva Jablonka thinks you need unlimited associative learning, and she would let the insects and crustaceans back in, but hesitates over those worms. The idea behind associative learning is again that consciousness takes you away from stereotyped behaviour and allows more complex and flexible responses – in this case because you can, for example, associate complex sets of stimuli and treat them as one new stimulus, quite an appealing idea.

Really it seems to me that all these interesting efforts are going after somewhat different conceptions of consciousness. I think it was Ned Block who called it a ‘mongrel’ concept; there’s little doubt that we use it in very varied ways, to describe the property of a worm that’s still moving at one end, to the ability to hold explicit views about the beliefs of other conscious entities at the other. We don’t need one theory of consciousness, we need a dozen.

humoursWorse than wrong? A trenchant piece from Michael Graziano likens many theories of consciousness to the medieval theory of humours; in particular the view that laziness is due to a build up of phlegm. It’s not that the theory is wrong, he says – though it is – it’s that it doesn’t even explain anything.

To be fair I think the theory of the humours was a little more complex than that, and there is at least some kind of hand-waving explanatory connection between the heaviness of phlegm and slowness of response. According to Graziano such theories flatter our intuitions; they offer a vague analogy which feels metaphorically sort of right – but, on examination, no real mechanism. His general point is surely very sound; there are indeed too many theories about conscious experience that describe a reasonably plausible process without ever quite explaining how the process magically gives rise to actual feeling, to the ineffable phenomenology.

As an example, Graziano mentions a theory that neural oscillations are responsible for consciousness; I think he has in mind the view espoused by Francis Crick and others that oscillations at 40 hertz give rise to awareness. This idea was immensely popular at one time and people did talk about “40 hertz” as though it was a magic key. Of course it would have been legitimate to present this as an enigmatic empirical finding, but the claim seemed to be that it was an answer rather than an additional question. So far as I know Graziano is right to say that no-one ever offered a clear view as to why 40 hertz had this exceptional property, rather than 30 or 50, or for that matter why co-ordinated oscillation at any frequency should generate consciousness. It is sort of plausible that harmonising on a given frequency might make parts of the brain work together in some ways, and people sometimes took the view that synchronised firing might, for example, help explain the binding problem – the question of how inputs from different senses arriving at different times give rise to a smooth and flawlessly co-ordinated experience. Still, at best working in harmony might explain some features of experience: it’s hard to see how in itself it could provide any explanation of the origin or essential nature of consciousness. It just isn’t the right kind of thing.

As a second example Graziano boldly denounces theories based on integrated information. Yes, consciousness is certainly going to require the integration of a lot of information, but that seems to be a necessary, not a sufficient condition. Intuitively we sort of imagine a computer getting larger and more complex until, somehow, it wakes up. But why would integrating any amount of information suddenly change its inward nature? Graziano notes that some would say dim sparks of awareness are everywhere, so that linking them gives us progressively brighter arrays. That, however, is no explanation, just an even worse example of phlegm.

So how does Graziano explain consciousness? He concedes that he too has no brilliant resolution of the central mystery. He proposes instead a project which asks, not why we have subjective experience, but why we think we do: why we say we do with such conviction. The answer, he suggests, is in metacognition. (This idea will not be new to readers who are acquainted with Scott Bakker’s Blind Brain Theory.) The mind makes models of the world and models of itself, and it is these inaccurate models and the information we generate from them that makes us see something magic about experience. In the brief account here I’m not really sure Graziano succeeds in making this seem more clear-cut than the theories he denounces. I suppose the parallel existence of reality and a mental model of reality might plausibly give rise to an impression that there is something in our experience over and above simple knowledge of the world; but I’m left a little nervous about whether that isn’t another example of the kind of intuition-flattering the other theories provide.

This kind of metacognitive theory tends naturally to be a sceptical theory; our conviction that we have subjective experience proceeds from an error or a defective model, so the natural conclusion, on grounds of parsimony if no others, is that we are mistaken and there is really nothing special about our brain’s data processing after all.

That may be the natural conclusion, but in other respects it’s hard to accept. It’s easy to believe that we might be mistaken about what we’re experiencing, but can we doubt that we’re having an experience of some kind? We seem to run into quasi-Cartesian difficulties.

Be that as it may Graziano deserves a round of applause for his bold (but not bilious) denunciation of the phlegm.

Newton in doubtConsciousness is not a problem, says Michael Graziano in an Atlantic piece that is short and combative. (Also, I’m afraid, pretty sketchy in places. Space constraints might be partly to blame for that, but can’t altogether excuse some sweeping assertions made with the broadest of brushes.)

Graziano begins by drawing an analogy with Newton and his theory of light. The earlier view, he says, was that white light was pure, and colour happened when it was ‘dirtied’ by contact with the surfaces of coloured objects. The detail of exactly how this happened was a metaphysical ‘hard problem’. Newton dismissed all that by showing first, that white light is in fact a mixture of all colours, and second, that our vision produces only an inaccurate and simplified model of the reality, with only three different colour receptors.

Consciousness itself, Graziano says, is also a misleading model in a somewhat similar way, generated when the brain represents its own activity to itself. In fact, to be clear, consciousness as represented doesn’t happen; it is a mistaken construct, the result of the good-enough but far from perfect apparatus bequeathed to us by evolution (this sounds sort of familiar).

We should be clear that it is really Hard Problem consciousness that is the target here, the consciousness of subjective experience and of qualia. Not that the other sort is OK: Graziano dismisses the Easy Problem kind of consciousness, more or less in passing, as being no problem at all…

These days it’s not hard to understand how the brain can process information about the world, how it can store and recall memories, how it can construct self knowledge including even very complex self knowledge about one’s personhood and mortality. That’s the content of consciousness, and it’s no longer a fundamental mystery. It’s information, and we know how to build computers that process information.

Amazingly, that’s it. Graziano writes in an impatient tone; I have to confess to a slight ruffling of my own patience here; memory is not hard to understand? I had the impression that there were quite a number of unimpeachably respectable scientists working on the neurology of memory, but maybe they’re just doing trivial detail, the equivalent of butterfly collecting, or who knows, philosophy? …we know how to build computers… You know it’s not the 1980s any more? Yet apparently there are still clever people who think you can just say that the brain is a computer and that’s not only straightforwardly true, but pretty much a full explanation? I mean, the brain is also meat, and we know how to build tools that process meat; shall we stop there and declare the rest to be useless metaphysics?

‘Information’, as we’ve often noted before, is a treacherous, ambiguous word. If we mean something akin to data, then yes, computers can handle it; if we mean something akin to understanding, they’re no better than meat cleavers. Nothing means anything to a computer, while human consciousness reads and attributes meanings with prodigal generosity, arguably as its most essential, characteristic activity. No computer was ever morally responsible for anything, while our society is built around the idea that human beings have responsibilities, rights, and property. Perhaps Graziano has debunking arguments for all this that he hasn’t leisure to tell us about; the idea that they are all null issues with nothing worthwhile to be said about them just doesn’t fly.

Anyway, perhaps I should keep calm because that’s not even what Graziano is mainly talking about. He is really after qualia, and in that area I have some moderate sympathy with him; I think it’s true that the problem of subjective experience is most often misconceived, and it is quite plausible that the limitations of our sensory apparatus and our colour vision in particular contribute to the confusion. There is a sophisticated argument to be made along these lines: unfortunately Graziano’s isn’t it; he merely dismisses the issue: our brain plays us false and that’s it. You could perhaps get away with that if the problem were simply about our belief that we have qualia; it could be that the sensory system is just misinforming us, the way it does in the case of optical illusions. But the core problem is about people’s actual direct experience of qualia. A belief can be wrong, but an experience is still an experience even if it’s a misleading one, and the existence of any kind of subjective experience is the real core of the matter. Yes, we can still deny there is any such thing, and some people do so quite cogently, but to say that what I’m having now is not an experience but the mere belief that I’m having an experience is hard and, well, you know, actually rather metaphysical…

On examination I don’t think Graziano’s analogy with Newton works well. It’s not clear to me why the ‘older’ view is to be characterised as metaphysical (or why that would mean it was worthless). Shorn of the emotive words about dirt, the view that white light picks up colour from contact with coloured things, the way white paper picks up colour from contact with coloured crayons, seems a reasonable enough scientific hypothesis to have started with. It was wrong, but if anything it seems simpler and less abstract than the correct view. Newton himself would not have recognised any clear line between science and philosophy, and in some respects he left the true nature of light a more complicated matter, not fully resolved. His choice of particles over waves has proved to be an over-simplification and remains the subject of some cloudy ontology to this day.

Worse yet, if you think about it, it was Newton who first separated the two realms: colour as it is in the world and colour as we experience it. This is the crucial distinction that opened up the problem of qualia, first recognisably stated by Locke, a fervent admirer of Newton, some years after Newton’s work. You could argue therefore, that if the subject of qualia is a mess, it is a mess introduced by Newton himself – and scientists shouldn’t castigate philosophers for trying to clear it up.

grazianoYes: I feel pretty sure that anyone reading this is indeed conscious. However, the NYT recently ran a short piece from Michael S. A. Graziano which apparently questioned it. A fuller account of his thinking is in this paper from 2011; the same ideas were developed at greater length in his book Consciousness and the Social Brain

I think the startling headline on the NYT piece misrepresents Graziano somewhat. The core of his theory is that awareness is in some sense a delusion, the reality of which is simple attention. We have ways of recognising the attention of other organisms, and what it is fixed on (the practical value of that skill in environments where human beings may be either hunters or hunted is obvious): awareness is just our garbled version of attention. he offers the analogy of colour. The reality out there is different wavelengths of light: colour, our version of that, is a slightly messed-up, neatened, artificial version which is nevertheless very vivid to us in spite of being artificial to a remarkably large extent.

I don’t think Graziano is even denying that awareness exists, in some sense: as a phenomenon of some kind it surely does: what he means is more that it isn’t veridical: what it tells us about itself, and what it tells us about attention, isn’t really true. As he acknowledges in the paper, there are labelling issues here, and I believe it would be possible to agree with the substance of what he says while recasting it in terms that look superficially much more conventional.

Another labelling issue may lurk around the concept of attention. On some accounts, it actually presupposes consciousness: to direct one’s attention towards something is precisely to bring it to the centre of your consciousness. That clearly isn’t what Graziano means: he has in mind a much more basic meaning. Attention for him is something simple like having your sensory organs locked on to a particular target. This needs to be clear and unambiguous, because otherwise we can immediately see potential problems over having to concede that cameras or other simple machines are capable of attention; but I’m happy to concede that we could probably put together some kind of criterion, perhaps neurological, that would fit the bill well enough and give Graziano the unproblematic materialist conception of attention that he needs.

All that looks reasonably OK as applied to other people, but Graziano wants the same system to supply our own mistaken impression of awareness. Just as we track the attention of others with the false surrogate of awareness, we pick up our own attentive states and make the same kind of mistake. This seems odd: when I sense my own awareness of something, it doesn’t feel like a deduction I’ve made from objective evidence about my own behaviour: I just sense it.  I think Graziano actually wants it to be like that for other people too. He isn’t talking about rational, Sherlock Holmes style reasoning about the awareness of other people, he has in mind something like a deep, old, lizard-brain kind of thing; like the sense of somebody there that makes the hairs rise on the back of the neck  and your eyes quickly saccade towards the presumed person.

That is quite a useful insight, because what Graziano is concerned to deny is the reality of subjective experience, of qualia, in a word. To do so he needs to be able to explain why awareness seems so special when the reality is nothing more than information processing. I think this remains a weak spot in the theory, but the idea that it comes from a very basic system whose whole function is to generate a feeling of ‘something there’ helps quite a bit, and is at least moderately compatible with my own intuitions and introspections.What Graziano really relies on is the suggestion that awareness is a second-order matter: it’s a cognitive state about other cognitive states, something we attribute to ourselves and not, as it seems to be, directly about the real world. It just happens to be a somewhat mistaken cognitive state.

That still leaves us in some difficulty over the difference between me and other people. If my sense of my own awareness is generated in exactly the same way as my sense of the awareness of others, it ought to seem equally distant  – but it doesn’t, it seems markedly more present and far less deniable.

More fundamentally, I still don’t really see why my attention should be misperceived. In the case of colours, the misrepresentation of reality comes from two sources, I think. One is the inadequacy of our eyes; our brain has to make do with very limited data on colour (and on distance and other factors) and so has to do things like hypothesising yellow light where it should be recognising both red and green, for example. Second, the brain wants to make it simple for us and so tries desperately to ensure that the same objects always look the same colour, although the wavelengths being received actually vary according to conditions. I find it hard to see what comparable difficulties affect our perception of attention. Why doesn’t it just seem like attention? Graziano’s view of it as a second-order matter explains how it can be wrong about attention, but not really why.

So I think the theory is less radical than it seems, and doesn’t quite nail the matter on some important points: but it does make certain kinds of sense and at the very least helps keep us roused from our dogmatic slumbers. Here’s a wild thought inspired (but certainly not endorsed) by Graziano. Suppose our sense of qualia really does come from a kind of primitive attention-detecting module. It detects our own attention and supplies that qualic feel, but since it also (in fact primarily) detects other people’s attention, should it not also provide a bit of a qualic feel for other people too? Normally when we think of our beliefs about other people, we remain in the explicit, higher realms of cognition: but what if we stay at a sort of visceral level, what if we stick with that hair-on-the back-of the-neck sensation? Could it be that now and then we get a whiff of other people’s qualia? Surely too heterodox an idea to contemplate…