Posts tagged ‘HOT’

Emotions like fear are not something inherited from our unconscious animal past. Instead they arise from the higher-order aspects that make human thought conscious. That (if I’ve got it right) is the gist of an interesting paper by LeDoux and Brown.

A mainstream view of fear (the authors discuss fear in particular as a handy example of emotion, on the assumption that similar conclusions apply to other emotions) would make it a matter of the limbic system, notably the amygdala, which is known to be associated with the detection of threats. People whose amygdalas have been destroyed become excessively trusting, for example – although as always things are more complicated than they seem at first and the amygdalas are much more than just the organs of ‘fear and loathing’. LeDoux and Brown would make fear a cortical matter, generated only in the kind of reflective consciousness possessed by human beings.

One immediate objection might be that this seems to confine fear to human beings, whereas it seems pretty obvious that animals experience fear too. It depends, though, what we mean by ‘fear’. LeDoux and Brown would not deny that animals exhibit aversive behaviour, that they run away or emit terrified noises; what they are after is the actual feeling of fear. LeDoux and Brown situate their concept of fear in the context of philosophical discussion about phenomenal experience, which makes sense but threatens to open up a larger can of worms – nothing about phenomenal experience, including its bare existence, is altogether uncontroversial. Luckily I think that for the current purposes the deeper issues can be put to one side; whether or not fear is a matter of ineffable qualia we can probably agree that humanly conscious fear is a distinct thing. At the risk of begging the question a bit we might say that if you don’t know you’re afraid, you’re not feeling the kind of fear LeDoux and Brown want to talk about.

On a traditional view, again, fear might play a direct causal role in behaviour. We detect a threat, that causes the feeling of fear, and the feeling causes us to run away. For LeDoux and Brown, it doesn’t work like that. Instead, while the threat causes the running away, that process does not in itself generate the feeling of fear. Those sub-cortical processes, along with other signals, feed into a separate conscious process, and it’s that that generates the feeling.

Another immediate objection therefore might be that the authors have made fear an epiphenomenon; it doesn’t do anything. Some, of course, might embrace the idea that all conscious experience is epiphenomenal; a by-product whose influence on behaviour is illusory. Most people, though, would find it puzzling that the brain should go to the trouble of generating experiences that never affect behaviour and so contribute nothing to survival.

The answer here, I think, comes from the authors’ view of consciousness. They embrace a higher-order theory (HOT). HOTs (there are a number of variations) say that a mental state is conscious if there is another mental state in the same mind which is about it – a Higher Order Representation (HOR); or to put it another way, being conscious is being aware that you’re aware. If that is correct, then fear is a natural result of the application of conscious processes to certain situations, not a peculiar side-effect.

HOTs have been around for a long time: they would always get a mention in any round-up of the contenders for an explanation of consciousness, but somehow it seems to me they have never generated the little bursts of excitement and interest that other theories have enjoyed. LeDoux and Brown suggest that other theories of emotion and consciousness either are ‘first -order’ theories explicitly, or can be construed as such. They defend the HOT concept against one of the leading objections, which is that it seems to be possible to have HORs of non-existent states of awareness. In Charles Bonnet, syndrome, for example, people who are in fact blind have vivid and complex visual hallucinations. To deal with this, the authors propose to climb one order higher; the conscious awareness, they suggest, comes not from the HOR of a visual experience but from the HOR of a HOR: a HOROR, in fact. There clearly is no theoretical limit to the number of orders we can rise to, and there’s some discussion here about when and whether we should call the process introspection.

I’m not convinced by HOTs myself. The authors suggest that single-order theory implies there can be conscious states of which we are not aware, which seems sort of weird: you can feel fear and not know you’re feeling fear? I think there’s a danger here of equivocating between two senses of ‘aware’. Conscious states are states of awareness, but not necessarily states we are aware of; something is in awareness if we are conscious; but that’s not to say that the something includes our awareness itself. I would argue, contrarily, that there must be states of awareness with no HOR; otherwise, what about the HOR itself? If HORs are states of awareness themselves, each must have its own HOR, and so on indefinitely. If they’re not, I don’t see how the existence of an inert representation can endow the first-order state with the magic of consciousness.

My intuitive unease goes a bit wider than that, too. The authors have given a credible account of a likely process, but on this account fear looks very like other conscious states. What makes it different – what makes it actually fearful? It seems possible to imagine that I might perform the animal aversive behaviour, experience a conscious awareness of the threat and enter an appropriate conscious state without actually feeling fear. I have no doubt more could be said here to make the account more plausible and in fairness LeDoux and Brown could well reply that nobody has a knock-down account of phenomenal experience, with their version offering a lot more than some.

In fact, even though I don’t sign up for a HOT I can actually muster a pretty good degree of agreement nonetheless. Nobody, after all, believes that higher order mental states don’t exist (we could hardly be discussing this subject if they didn’t). In fact, although I think consciousness doesn’t require HORs, I think they are characteristic of its normal operation and in fact ordinary consciousness is a complex meld of states of awareness at several different levels. If we define fear the way LeDoux and Brown do, I can agree that they have given a highly plausible account of how it works without having to give up my belief that simple first-order consciousness is also a thing.


So now let’s look at the review by Richard Brown of Rocco J. Gennaro’s new book, which sets out his HOT.  I should disclose that I have not read Gennaro’s book, so I’m merely reviewing a review of a theory. You could call it a higher order review.

Gennaro’s own concerns feature concepts strongly: his theory includes conceptualism, the belief that concepts provide key structure for our conscious experience.  This causes him some difficulty over animals and infants, as he needs them to have sufficiently advanced concepts to form the required higher order awareness. He needs at least some account of how the required concepts are acquired (or how they came to be innate), and he needs to avoid getting into the bootstrap bind where you need to have sophisticated conceptual structures in order to pick up the concepts you need in order to have sophisticated conceptual structures.

My personal bias is that conceptualism tends to bring unnecessary complications, and in this particular case I’m not sure why we need to make the weather so heavy (though no doubt Gennaro has his reasons). All we need is the awareness of an awareness: the higher order awareness does not need to look through to the objects in the external world. The conceptual apparatus required surely ought therefore to be modest, and I wouldn’t fight very hard against the idea that it could be built in or be the result of a very early internal rewiring exercise in the infant mammalian brain.

The main point of interest for us is the difference which Brown sets out between his own view and Gennaro’s. This hinges on a fundamental point: are we talking about higher order awareness of a mental state (Gennaro), or of our being in that mental state (Brown)? At this point I’d say I find Brown’s view, which he characterises as the non-relational view, more appealing. It seems important to specify that the awareness involved must be ours, after all.

However, both sides claim that their view is best able to deal with the kind of objections raised by Block and discussed last time, arising from cases where we have the higher order awareness but actually through some error the lower-order awareness which it targets is not actually there. Gennaro, it seems, wants to disqualify these states altogether: where the first-order state is not there, there’s no consciousness. If you’re not seeing something red, you can’t have the subjective consciousness of redness. This is neat in its way, but seems arbitrary (How come subjective experience, of all things, comes to have a special kind of immunity from error?), and surely we want to retain the possibility of a subjective experience not based in reality? I can see that some might argue that dreams lack real subjective experience, but are we prepared to say the same of illusions and mirages? That seems a high price to be paying.

Brown’s escape route is quite different: by adopting the non-relational view he can cut free from the first-order state altogether. Who cares whether it’s there or not? It’s just about the right kind of second-order state, that’s all. This may seem a little weird, but after all the orthodox view of qualia, our subjective experiences, is that they are largely decoupled from ordinary causal reality. On Brown’s view, if we see green, we can have the experience of red without invalidating the experience. We’ll still behave as though we were having the experience of green.  Block might denounce our qualia as fake, but meh, if that’s what you mean by fake, all qualia were always fake, so who cares?

The logic of that seems faultless, but I couldn’t help feeling that my sympathies were swinging back to Gennaro somewhat. Brown mentions a second problem, the problem of the rock: why can’t we make a rock conscious by having the right kind of second-order mental state about it? For Brown’s decoupled  view, there’s no problem because we’re not even talking about the first order awareness – rock, schmock, it’s simply irrelevant. Gennaro does have to face the issue and it seems he seeks to do it simply by disqualifying rocks with an additional rule or specification. Brown considers this another unattractively arbitrary lash-up, and perhaps it is, but in another light it seems far closer to common sense (though of course the realm of common sense is some way off by now in any event).

For myself the net effect of the discussion is to make me feel more strongly than before that if we are to have a HOT (and I’m not absolutely wedded to that in itself), we’d do much better to stick with what Block calls the unambitious variety, the kind that doesn’t seek to explain subjective experience or exorcise those deadly sirens we call qualia.

Higher OrderYou may have seen the very interesting review that Micha kindly mentioned recently. I plan to discuss that next week, but before talking about Higher Order Theories (HOTs) it seemed best to set the context by talking about Ned Block’s paper which seeks to demolish them.

Higher Order theories come in many flavours, but the basic proposition is that a mental event, a thought or a feeling, is conscious if there is another thought about it, that original mental event. The basic intuition is that you can be aware of something unconsciously, but when you’re aware of your awareness it’s conscious.

Not everyone likes this perspective (Roger Penrose caustically pointed out that pointing a video camera at itself doesn’t make it conscious) and some would say either that it only explains certain varieties of consciousness or that it only explains certain aspects of consciousness. Nevertheless, HOTs have had a long run as respectable contenders, representing one of the major areas where we might choose to look for The Answer.

Block’s paper last year was unusual in seeking to offer something like a knock-down destruction of the case, or perhaps it would be more accurate to sought he meant to pursue the HOTists until their last hiding place had been flushed out. His targets were not the modest theorists who claim that HOTs may explain some varieties of aspects of consciousness, but the ones he characterised as ‘ambitious’: in particular those who claim HOTs could explain the ‘what-it- is-likeness’ (let’s call it WIIL) of conscious experience.

The starting point is the uncomfortable fact that we can have thoughts about being in conscious states we’re not in fact in. We can think we’re seeing red when in fact we’re seeing green, or not seeing anything at all. You might well feel that this in itself is something of a blow for HOTs, and your first reaction might be that they should give up any claim of a conscious state where there is no state to work with. That sounds sensible but the retreat is not so easy as it seems if we want to retain WIIL for dreams and illusions, as we surely do.  In any case, Block’s targets take the opposite path: sure there can be WIIL in those cases, they reply.

Now Block springs the trap. So you’re saying, he observes, that an episode is conscious if it is the object of a simultaneous higher order thought?  And that thought is a sufficient condition for a conscious episode. Yet it’s also a necessary condition that that episode is the object of a higher order thought. Yet in this case we have only the one, higher-order thought to work with (and we can assume it ain’t self-referential). So there is no conscious episode. We’ve got necessary and sufficient conditions which are not compatible – what madness is this?

There is a way out which those unused to philosophical discussion may find a little odd: this consists of saying that in these cases, where we have a second-order thought about an experience we’re not actually having, there is an object of the second order thought after all: it’s simply one that doesn’t exist, that’s all.  We must remember here that the objects of thought are slippery customers; we often think about things that don’t exist (Pokemon, the sixth wife of Henry VII, the house I would have built if I had won the lottery, square circles).

But, says Block, if you take that route, where’s your WIIL (or maybe in this case it should be WIIAL –What It Isn’t Actually Like)? It’s now fake WIIL – and you can’t rest content with that.

I’ve omitted some important technicalities and details in the foregoing, but I hope the gist comes through: where does it leave us?  It seems an effective argument to me, and I would add that for those who are seeking the essence of WIIL, it seems intuitively unlikely to me that it could ever have resided in thoughts about thoughts: that brings it all back into the head, whereas what it is like ought to out there with ‘it’. Those who never believed in WIIL will not, of course, be troubled by any of this.

So following Block’s demolition, the advocates of HOT admitted their error, thanked him for clarifying, and issued a full retraction. No, of course they didn’t, as we shall see…