Posts tagged ‘Prinz’

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.

jennifer2Are ideas conscious at all? Neuroscience of Consciousness is a promising new journal from OUP introduced by the editor Anil Seth here. It has an interesting opinion piece from David Kemmerer which asks – are we ever aware of concepts, or is conscious experience restricted to sensory, motor and affective states?

On the face of it a rather strange question? According to Kemmerer there are basically two positions. The ‘liberal’ one says yes, we can be aware of concepts in pretty much the same kind of way we’re aware of anything. Just as there is a subjective experience when we see a red rose, there is another kind of subjective experience when we simply think of the concept of roses. There are qualia that relate to concepts just as there are qualia that relate to colours or smells, and there is something it is like to think of an idea. Kemmerer identifies an august history for this kind of thinking stretching back to Descartes.

The conservative position denies that concepts enter our awareness. While our behaviour may be influenced by concepts, they actually operate below the level of conscious experience. While we may have the strong impression that we are aware of concepts, this is really a mistake based on awareness of the relevant words, symbols, or images. The intellectual tradition behind this line of thought is apparently a little less stellar – Kemmerer can only push it back as far as Wundt – but it is the view he leans towards himself.

So far so good – an interesting philosophical/psychological issue. What’s special here is that in line with the new journal’s orientation Kemmerer is concerned with the neurological implications of the debate and looks for empirical evidence. This is an unexpected but surely commendable project.

To do it he addresses three particular theories. Representing the liberal side he looks at Global Neural Workspace Theory (GNWT) as set out by Dehaene, and Tononi’s Integrated information Theory (IIT)’ on the conservative side he picks the Attended Intermediate-Level Representation Theory (AIRT) of Prinz. He finds that none of the three is fully in harmony with the neurological evidence, but contends that the conservative view has distinct advantages.

Dehaene points to research that identified specific neurons in a subject’s anterior temporal lobes that fire when the subject is shown a picture of, say, Jennifer Aniston (mentioned on CE – rather vaguely). The same neuron fires when shown photographs, drawing, or other images, and even when the subject is reporting seeing a picture of Aniston. Surely then, the neuron in some sense represents not an image but the concept of Jennifer Aniston?  against theconservative view Kemmerer argues that while a concept may be at work, imagery is always present in the conscious mind; indeed, he contends,  you cannot think of ‘Anistonicity’ in itself without a particular image of Aniston coming to mind. Secondly he quotes further research which shows that deterioration of this portion of the brain impairs our ability to recognise, but not to see, faces. This, he contends, is good evidence that while these neurons are indeed dealing with general concepts at some level, they are contributing nothing to conscious awareness, reinforcing the idea that concepts operate outside awareness. According to Tononi we can be conscious of the idea of a triangle, but how can we think of a triangle without supposing it to be equilateral, isosceles, or scalene?

Turning to the conservative view, Kemmerer notes that AIRT has awareness at a middle level, between the jumble of impressions delivered by raw sensory input on the one hand, and the invariant concepts which appear at the high level. Conscious information must be accessible but need not always be accessed.  It is implemented as gamma vector waves. This is apparently easier to square with the empirical data than the global workspace, which implies that conscious attention would involve a shift into the processing system in the lateral prefrontal cortex where there is access to working memory – something not actually observed in practice. Unfortunately although the AIRT has a good deal of data on its side the observed gamma responses don’t in fact line up with reported experience in the way you would expect if it’s correct.

I think the discussion is slightly hampered by the way Kemmerer uses ‘awareness’ and ‘consciousness’ as synonyms. I’d be tempted to reserve awareness for what he is talking about, and allow that concepts could enter consciousness without our being (subjectively) aware of them. I do think there’s a third possibility being overlooked in his discussion – that concepts are indeed in our easy-problem consciousness while lacking the hard-problem qualia that go with phenomenal experience. Kemmerer alludes to this possibility at one point when he raises Ned Block’s distinction between access and phenomenal  (a- and p-consciousness), but doesn’t make much of it.

Whatever you think of Kemmerer’s ambivalent;y conservative conclusion, I think the way the paper seeks to create a bridge between the philosophical and the neurological is really welcome and, to a degree, surprisingly successful. If the new journal is going to give us more like that it will definitely be a publication to look forward to.

 

kiss… is not really what this piece is about (sorry). It’s an idea I had years ago for a short story or a novella. ‘Lust’ here would have been interpreted broadly as any state which impels a human being towards sex. I had in mind a number of axes defining a general ‘lust space’. One of the axes, if I remember rightly, had specific attraction to one person at one end and generalised indiscriminate enthusiasm at the other; another went from sadistic to masochistic, and so on. I think I had eighty-one basic forms of lust, and the idea was to write short episodes exemplifying each one: in fact, to interweave a coherent narrative with all of them in.

My creative gifts were not up to that challenge, but I mention it here because one of the axes went from the purely intellectual to the purely physical. At the intellectual extreme you might have an elderly homosexual aristocrat who, on inheriting a title, realises it is his duty to attempt to procure an heir. At the purely physical end you might have an adolescent boy on a train who notices he has an erection which is unrelated to anything that has passed through his mind.

That axis would have made a lot of sense (perhaps) to Luca Barlassina and Albert Newen, whose paper in Philosophy and Phenomenological Research sets out an impure somatic theory of the emotions. In short, they claim that emotions are constituted by the integration of bodily perceptions with representations of external objects and states of affairs.

Somatic theories say that emotions are really just bodily states. We don’t get red in the face because we’re angry, we get angry because we’ve become red in the face. As no less an authority than William James had it:

The more rational statement is that we feel sorry because we cry, angry because we strike, afraid because we tremble, and not that we cry, strike, or tremble, because we are sorry, angry, or fearful, as the case may be. Without the bodily states following on the perception, the latter would be purely cognitive in form, pale, colorless, destitute of emotional warmth.

This view did not appeal to everyone, but the elegantly parsimonious reduction it offers has retained its appeal, and Jesse Prinz has put forward a sophisticated 21st century version. It is Prinz’s theory that Barlassina and Newen address; they think it needs adulterating, but they clearly want to build on Prinz’s foundations, not reject them.

So what does Prinz say? His view of emotions fits into the framework of his general view about perception: for him, a state is a perceptual state if it is a state of a dedicated input system – eg the visual system. An emotion is simply a state of the system that monitors our own bodies; in other words emotions are just perceptions of our own bodily states.  Even for Prinz, that’s a little too pure: emotions, after all, are typically about something. They have intentional content. We don’t just feel angry, we feel angry about something or other. Prinz regards emotions as having dual content: they register bodily states but also represent core relational themes (as against say, fatigue, which both registers and represents a bodily state). On top of that, they may involve propositional attitudes, thoughts about some evocative future event, for example, but the propositional attitudes only evoke the emotions, they don’t play any role in constituting them. Further still, certain higher emotions are recalibrati0ns of lower ones: the simple emotion of sadness is recalibrated so it can be controlled by a particular set of stimuli and become guilt.

So far so good. Barlassina and Newen have four objections. First, if Prinz is right, then the neural correlates of emotion and the perception of the relevant bodily states must just be the same. Taking the example of disgust, B&N argue that the evidence suggests otherwise: interoception, the perception of bodily changes, may indeed cause disgust, but does not equate to it neurologically.

Second, they see problems with Prinz’s method of bringing in intentional content. For Prinz emotions differ from mere bodily feeling because they represent core relational themes. But, say B&N, what about ear pressure? It tells us about unhealthy levels of barometric pressure and oxygen, and so relates to survival, surely a core relational theme: and it’s certainly a perception of a bodily state – but ear pressure is not an emotion.

Third, Prinz’s account only allows emotions to be about general situations; but in fact they are about particular things. When we’re afraid of a dog, we’re afraid of that dog, we’re not just experiencing a general fear in the presence of a specific dog.

Fourth, Prinz doesn’t fully accommodate the real phenomenology of emotions. For him, fear of a lion is fear accompanied by some beleifs about a lion: but B&N maintain that the directedness of the emotion is built in, part of the inherent phenomenology.

Barlassina and Newen like Prinz’s somatic leanings, but they conclude that he simply doesn’t account sufficiently for the representative characteristics of emotions: consequently they propose an ‘impure’ theory by which emotions are cognitive states constituted when interoceptive states are integrated with with perceptions of external objects or states of affairs.

This pollution or elaboration of the pure theory seems pretty sensible and B&N give a clear and convincing exposition. At the end of the day it leaves me cold not because they haven’t done a good job but because I suspect that somatic theories are always going to be inadequate: for two reasons.

First, they just don’t capture the phenomenology. There’s no doubt at all that emotions are often or typically characterised or coloured by perception of distinctive bodily states, but is that what they are in essence? It doesn’t seem so. It seems possible to imagine that I might be angry or sad without a body at all: not, of course, in the same good old human way, but angry or sad nevertheless. There seems to be something almost qualic about emotions, something over and above any of the physical aspects, characteristic though they may be.

Second, surely emotions are often essentially about dispositions to behave in a certain way? An account of anger which never mentions that anger makes me more likely to hit people just doesn’t seem to cut the mustard. Even William James spoke of striking people. In fact, I think one could plausibly argue that the physical changes associated with an emotion can often be related to the underlying propensity to behave in a certain way. We begin to breathe deeply and our heart pounds because we are getting ready for violent exertion, just as parallel cognitive changes get us ready to take offence and start a fight. Not all emotions are as neat as this: we’ve talked in the past about the difficulty of explaining what grief is for. Still, these considerations seem enough to show that a somatic account, even an impure one, can’t quite cover the ground.

Still, just as Barlassina and Newen built on Prinz, it may well be that they have provided some good foundation work for an even more impure theory.