Archive for February, 2011

Picture: ephaptic consciousness. The way the brain works is more complex than we thought. That’s a conclusion that several pieces of research over recent years have suggested for one reason or another: but some particularly interesting conclusions are reported in a paper in Nature Neuroscience (Anastassiou, Perin, Markram, and Koch). It has generally been the assumption that neurons are effectively isolated, interacting only at synapses: it was known that they could be influenced by each other’s electric fields, but it was generally thought that given the typically tiny fields involved, these effects could be disregarded. The only known exceptions of any significance were in certain cases where unusually large fields could induce ‘ephaptic coupling ‘ interfering with the normal working of neurons and cause problems.

Given the microscopic sizes involved and the weakness of the fields, measuring the actual influence of ephaptic effects is difficult, but for the series of experiments reported here a method was devised using up to twelve electrodes for a single neuron. It was found that extracellular fluctuation did produce effects within the neuron, at the minuscule level expected: however, although the effects were too small to produce any immediate additional action potentials, induced fluctuations in one neuron did influence neighbouring cells, producing a synchronisation of spike timing. In short, it turns out that neurons can influence each other and synchronise themselves through a mechanism completely independent of synapses.

So what? Well, first this may suggest that we have been missing an important part of the way the brain functions. That has obvious implications for brain simulations, and curiously enough, one of the names on the paper (he helped with the writing) is that of Henry Markram, leader of the most ambitious brain simulation project of all,Blue Brain.  Things seem to have gone quiet on that project since completion of ‘phase one’; I suppose it is awaiting either more funding or the advances in technology which Markram foresaw as the route to a total brain simulation. In the meantime it seems the new research shows that like all simulations to date Blue Brain was built on an incomplete picture, and as it stood was doomed to ultimate failure.

I suppose, in the second place, there may be implications for connectionism. I don’t think neural networks are meant to be precise brain simulations, but the suggestion that a key mechanism has been missing from our understanding of the brain might at least suggest that a new line of research, building in an equivalent mechanism to connectionist systems could yield interesting results.

But third and most remarkable, this must give a big boost to those who have suggested that consciousness resides in the brain’s electrical field: Sue Pockett, for one, but above all JohnJoe McFadden, who back in 2002 declared that the effects of the brain’s endogenous electromagnetic fields deserved more attention. Citing earlier studies which had shown modulation of neuron firing by very weak fields, he concluded:

By whatever mechanism, it is clear that very weak em field fluctuations are capable of modulating neurone-firing patterns. These exogenous fields are weaker than the perturbations in the brain’s endogenous em field that are induced
during normal neuronal activity. The conclusion is inescapable: the brain’s endogenous em field must influence neuronal information processing in the brain.

We may still hold back from agreeing that consciousness is to be identified with an electromagnetic field, but he certainly seems to have been ahead of the game on this.

Picture: Nicholas Humphrey. Nicholas Humphrey is back with what he presents as a new attempt to knock that Hard Problem of qualia on the head once and for all. Soul Dust is not, however, a brand new theory: rather he has dusted down (or dusted up) the ideas he presented in Seeing Red, added some new points and a lot of persuasive advocacy, much of it in the form of quotes. He has many really good, interesting quotes, the sort that impel you to look up the original for more: but on the whole I think it was a mistake to invoke the ‘raindrops on roses and whiskers on kittens’ of The Sound of Music when extolling the splendiferous nature of a qualia-filled world.

The basic proposition of the book has two parts.  The first is an account of perception and the self. Perception begins with a simple response to a stimulus – ‘redding’ if we’re seeing red. There are no qualia involved in that, but when we form a loop by perceiving our own redding it adds a special vividness which we project back on to the perceived object; seen as a property of the object, this reverberation in our brain (Humphrey speaks of ‘soul-hammering’)  naturally seems somewhat mysterious: it’s like one of those paradoxical objects in an Escher picture (Humphrey uses as his example the 3D object made by Richard Gregory, which from one angle appears to be an impossible Penrose triangle). The looping also contributes to the construction of ‘thick time’, the perception of the present as something with significant duration rather than an infinitesimal line dividing past and present.

The enchanted quality of experience sheds the same illusory magic on the perceiving self, and by extension on the thinking Ego which goes with it. All this is why the world seems so worth experiencing and why we seem to ourselves so well worth preserving: a qualia-free zombie wouldn’t have any great relish in life nor any particular reason to fear death. That’s the second part of the case: this business of ‘artificial’ qualic impressions has come about through evolution because the extra zest it confers gives the possessor of qualia a survival edge over zombie counterparts.

The book is an engaging and persuasive read: you feel you’ve spent some time in friendly conversation with a very civilised and erudite man who has seen deeply into some of the issues.  But there are a few problems.

The first is that the book isn’t really about qualia at all. Humphrey, reasonably enough perhaps, dismisses the idea of ineffable qualia that can’t be described and play no causal role in the world. Since he wants to give an evolutionary explanation, he has to take this stance: ineffable qualia couldn’t have survival value. But if they ain’t ineffable, they ain’t really qualia, and what we’re talking about ain’t really the Hard Problem. It’s the ineffability that’s hard to explain; take that away and explaining why sensations are vivid may be non-trivial, but it’s part of the Easy Problem.  I’m not altogether sure he realises it, but Humphrey has pitched his camp with Dennett and accordingly all he is really entitled to say is “what qualia?”.

Although they’re not ineffable, Humphrey still wants his qualia to be illusions, a magic lantern show rather than a radar system. Why is that? If our perceptions are not of ineffable qualia, can’t they just be of real qualities of actual things? One reason Humphrey wants them to be illusions is that he wants to use the fact to validate that much-quoted phraseology about there being “something is it like” to experience things: the thing it’s like can be the thing itself.  But also lurking somewhere in the back of Humphrey’s mind is, I suspect, that terrible old argument from error: because some of our perceptions are not of real things, none of them are – they’re all of proxies in our heads.

So everything that makes life seem worthwhile is actually an illusion? It’s a grim conclusion to reach, though Humphrey doesn’t seem to read it that way: he talks about the delight of experience and the wonder of the world as though he hadn’t begun by insisting that all these things are confidence tricks, quite false in fact. If Humphrey takes his own views seriously, he must be forced to conclude that in sober fact the zombies would be right: there actually is no particular reason to go on living and everything we value is in fact worthless. In fact, perhaps he does realise this, because he closes with an examination of the reasons why we go on living in the face of our undeniable mortality: not the actual reasons why we should go on living, but the deluded considerations that stop us topping ourselves immediately.  He concludes that belief in an afterlife, supported by such things as our experience of waking every day, as if from death, is a natural part of the human outlook and the main thing that keeps most of us going. I think in fact that the majority of people, faced with the fact of eventual death, simply don’t waste time worrying about something they can’t change. Humphrey seems to think that a natural reaction to the inevitability of eventual death is immediate suicide: that might be one emotional reaction but I think to most people the lack of logic in bringing forward the very thing you fear is too salient to make that an attractive course. Myself I think it’s possible that if we attain sufficient maturity we might come to realise that one good life is enough. You don’t have to be a pessimist or severely depressed to think that rightly understood, the law that everything has its termination amounts to a promise, not a threat.

What about the second point, that qualia are here because they have positive survival value? I like the idea of looking for an evolutionary explanation, but I don’t think Humphrey ever makes this really convincing.  The main argument seems to be that the extra pleasure given by qualia means we’re better motivated than zombies would be, and pay more attention.  Yet there are surely many unpleasant and repulsive qualia; logically one might suppose as many of those as pleasant, attractive ones.  Malthus tells us that most animals naturally live on the brink of starvation; having their constantly frustrated desire for food intensified doesn’t seem as obviously a good thing for them as it might be for us well-fed historical anomalies. Above all, aren’t qualia distracting? Isn’t it all too likely that while the qualophile animals are admiring the sunset they are more likely to be caught by the sabre-toothed tiger?

I think there is actually a potential argument here that Humphrey doesn’t use.  Most animals get by very largely on instinct and other relatively hard-wired behaviour; only humans have really broken free to do whatever their rational deliberations – or their irrational whims – suggest to them.  It could be argued that humans need qualia exactly to make the traditional sensory rewards for ‘good’ behaviour more potent in compensation for our greater ability to over-ride them. We need food to be more exciting and sex sexier to make us attend sufficiently to the basic biological imperatives instead of simply starving to death while reading or playing computer games (or committing suicide out of misplaced philosophical angst). That would make a certain kind of sense, anyway.

It may sound from the foregoing as if I radically disagree with everything Humphrey says, but that’s not the case at all: the book is a good rational effort in the right area, and it expresses some complex insights with marvellous lucidity. But  (alas, how many times have I said this over the years?) it’s not quite the Answer.

Picture: God. I worry sometimes about God. I suppose I’ve been a fairly consistent atheist all my life, though not particularly zealous: I realise that many people far cleverer than me have been committed believers in one religion or another and have written enlightening stuff about it which is well worth anyone’s time to read. I don’t really understand the apparently visceral hostility which people like Richard Dawkins display towards theism; for me it’s more that in itself it doesn’t seem a useful idea; instead it seems to be among the wilder pieces of metaphysics you could go in for (I enjoy wild metaphysics, of course – nothing better – but I don’t adopt it). Be that as it may, I used to think that certain conceptions of God were rationally available if you wanted them. ‘Geometrical’ Gods would be one example, where you just define something like ‘the universal total of awareness’ or ‘the origin of everything’ as God, and then stick to it even though on careful examination your defined entity turns out to bear no apparent resemblance to the one people talk to in church. A little more scary, Gods that are absent, indifferent, unkind, or systematically deceptive seemed viable enough so long as you realise they’re not really going to do any useful ontological work for you. They have a tendency to leave you with a theoretical mess slightly worse than the one you had to begin with, but if you want you can bring them along for the ride without egregious inconsistency.

Or so I thought: but in recent years I feel it’s been getting more difficult to accommodate the idea of a non-material conscious entity. In the old days, when we had no idea how any of this worked, God was useful as the source of consciousness: he’s got it and he bestows it on us. This view has not gone away and perhaps a modern version might be Peter Russell’s equation of God and consciousness. If our consciousnesses are God it puts a strangely introverted complexion on prayer; but I think what he really means is that our consciousnesses are fragments of the universal version which is God. For me, that has too strong a flavour of gnosticism (roughly, the belief that we’re all fragments of a divine being trapped by a ghastly cosmic accident in lumps of meat, and subject to a demiurge who falsely believes himself to be God. Why is gnosticism so popular, by the way? The secret esoteric doctrine always turns out to be gnostic. Come on, you heresiarchs: I was promised wild metaphysics!): I’m afraid for me gnosticism is one of those doctrines that resemble the legendary town in the mid-west of America that had a big sign saying Friend, if you’ve ended up here, you musta got on the wrong train somewhere.

At any rate, I find myself more in sympathy with Matt McCormick’s case that an omnipresent God wouldn’t be able to think because of his inability to draw the distinction between himself and the rest of the world. Although McCormick makes a cogent case, a determined theist could probably lash together a way of dealing with the problem of conscious omnipresence, but then there are others, possibly worse, associated with omniscience. God knows everything at once: he doesn’t suffer from our form of the binding problem (the issue of how our brain makes a smooth coherent sequence out of sounds, vision, touch, etc) because all the correct things are linked up; but has a worse one of his own because everything is bound with everything else. He can’t perceive some events as simultaneous and others as not, because he can’t stop thinking about any of them. How right the theologians were then, to say he lived in eternity rather than time: it was bound to look like eternity to him, at any rate, because he’s incapable of perceiving change.

But surely that’s all wrong: God can’t have a binding problem because the binding problem relates to the synchronisation of sensory data; and as a non-material being, he can’t have any senses (to see, you need material parts that can be affected by light, for example).  But then he needs no senses, because he already knows where everything is and what it looks like. What he has a problem with is coherence and progression. Consciousness, we know, is a stream, and thought is a sequence, but it seems God is going to be incapable of either because everything is constantly in his mind.

But again, perhaps that to is wrong, and we need to distinguish between what God knows and what he’s actually thinking about. We, after all, know lots of things without having them constantly in mind. That’s an attractive way of looking at it because it suggests that although God knows about your sins, he will most likely never get round to giving them any attention, given all the things he has to think about – a comforting if heterodox view.

Picking on the ‘omni’ problems – omnipotence has its own long-standing difficulties - may be attacking a soft target; unfortunately there are less abstract ones, too. We sort of know by now that consciousness is associated with the activity of complex neural structures, and an immaterial God hasn’t got neurons. We sort of know, too, that consciousness is associated with a family of cognitive abilities displayed in different degrees by different animals and arising out of a long process of evolution. We can see these abilites as being about the linking of sensory inputs and behavioural outputs, all the way from simple tropisms and reflexes through instinctive and thoughtful behaviour all the way to our largely detached meditations. We’ve already noted that God has no sensory inputs, and it’s a little hard to see how a non-material being can have material outputs either. Our minds grew out of processes intimately connected with the needs of a physical animal – the ‘three Fs’ of feeding, fighting, and reproducing, all of which seem to be at best optional extras as far as God is concerned. Why would an immaterial being ever go through cognitive processes primarily designed to facilitate existence in a domain entirely alien to it, and if it did, what could it use to implement those processes?

Perhaps a theist would say that I’m harping far too much on the lower aspects of consciousness: sure, it helps us avoid the sabre-tooths and chip flints, and obviously God isn’t much bothered in those areas; but what about the fancier aspects: what about qualia? A while back there did seem to be a move to recruit the Hard Problem as a crack in the otherwise solid wall of materialism which God might slip through, but it’s hard to see how God could have phenomenal experience. To begin with, it seems he doesn’t have sensory experience at all, for the reasons mentioned above; then again, if qualia are merely a matter of knowing what x is like he must have them in horrifying, mind-crushing, infinite simultaneous abundance.

What about intentionality, though? Perhaps God is a being composed of pure meaning, which would nicely account for his non-materiality. It looks attractive, but we surely don’t want God locked up in the Platonic realm where could have only the status of an inert abstraction.  Yet in the ordinary world intentionality only appears in two places: things made meaningful by us, and in those same old complex neural assemblies our brains, which God hasn’t got.

These random noodlings of mine don’t, of course, come near ruling out every possible conception of God (in fact the old man with a beard sitting on clouds starts to look pretty good, so long as he’s not immaterial); but he seems to be slowly getting more and more problematic. In the past it’s always been possible to shrug and take it that God is so far above our comprehension we shouldn’t expect all the answers; but the conclusion that God can’t be conscious seems too alarming and at the same time too clear to be dismissed.