Wednesday, 23 January 2008

Making up the Mind 7: Getting ahead by prediction


According to authors such as Anthony Kenny and Peter Hacker, the homunculus fallacy is to be understood as the fallacy of attributing to parts of organisms properties which can only sensibly be said to belong to the whole organism. I have followed Hacker and called this the 'mereological fallacy', instead reserving the 'homunculus fallacy' to describe a different conceptual confusion which arises when neuropsychologists attempt to describe the mechanics of perception, and end up writing as if the brain is some kind of mediating mechanism which serves up deliverances for the consciousness of an inner homunculus.


Along with the entifying fallacy (that of creating entities out of acts), these fallacies clearly work together, supporting one another in an unholy conceptual trinity. However I believe that the mereological fallacy is considerably less serious than the homunculus fallacy as I have described it. When authors such as Chris Frith describe the brain as thinking or remembering or inferring, we can usually translate out from this idiom without much trouble, and just remind ourselves that we have to do with metaphor here. But the homunculus fallacy makes for whole explanatory endeavours that are deeply misguided.


Consider for example how chapter 4 - Getting ahead by Prediction - continues. For several pages Frith describes various different learning paradigms (Thorndike, Skinner, Pavlov etc.), and sometimes talks of the brain predicting or learning or remembering or knowing. But the examples ("what our brain knows as a result of learning by association"; "we can see the brain predicting in this way if we look directly at the activity in nerve cells") can always be effortlessly translated out into a non-intentionalistic idiom. Frith is talking about the differential responses of the nervous system which causally support our knowing or learning, and for a shorthand has simply ascribed the psychological functions to the causal supports. No harm comes of it.


But now consider (pp. 101ff) the following Helmholtzian concern Frith has regarding how 'I experience myself in the world':

Consider a very simple action like walking round the room... I move and the world stays exactly where it is. And this is very odd because every time I move, this movement produces dramatic changes in what my brain senses about the world. Even just moving my eyes has a dramatic effect. On my retina, and again on my visual cortex at the back of my brain, a picture of the world is projected. But if Imove my eyes this projection will change completely. As I move my eye from left to right across the fir tree in the garden, the projection of the fir tree moves from the right to the left side of my retina. This is a dramatic change of sensation. And it raises a problem for my brain - is there a change in sensation because my eye is moving or because the fir free is moving?


Now what would make it the case that 'this is very odd'? Surely we would not expect the world to (appear to?) move when we walk around the place. Such movement of the world might render impossible the very possibility of perception. The only answer that presents itself is this: imagine if we were stuck behind our retinas, trying to read the world off from images that formed there. If that were our unfortunate dilemma, then of course we would need all the help we could get, and more, from cognitive processes. We would need some to bind together the two retinal images, some to reinvert them, others to stabilise them, and so on. At the end of it we would not be in touch with the world, perhaps, but at least we'd have a picture of it that stayed reasonably stable and was (but how would we ever know?) fairly reliable in its depiction. Frith presents no evidence (and what would that look like?) that this (being epistemically trapped on the receiving ends of neural deliveries from sense organs) is our predicament. Rather, he seems to simply assume it. For this reason the chapter presents its findings as if it is a remarkable discovery. As if we all assumed naively to start with that a 'picture of the world' could be read off 'retinal images' (because that is just what perception amounts to), and then found that things really couldn't be that simple, and there would need to be a lot of cognitive processes intervening between the ultimate 'image for consciousness' (or however we would have to describe it) and the original 'sensory input'.


Frith's mistake seems to be one of conflating the personal epistemic level of our contact with the world itself, and the subpersonal neurological level of the constitutive mechanics of vision. The personal element is pushed inwards at the end of the causal chain of the subpersonal dynamics. But this won't do: these really are two different levels of explanation and understanding, not two adjacent domains that are causally chained.


None of this is to say that the possibility of perception is not founded in the possibility of the brain reacting differently to identical changes in retinal stimulation when these changes are either due to object movement or to eye movement. That is surely a necessary precondition for the possibility of perception. Perhaps because of his homuncular 'mind as recipient of neurophysiological inputs' picture, Frith seems to think that perception would be simply a matter of passively receiving sensory stimuli, if it were not for the counfounding influence of personal movement on the retinal image. Yet we know that stable (personal-level) visual experience is dependent on our being able to make thousands of micromovements - it is - at the subpersonal level - an active (even 'enactive') process constituted by dynamic recursive loops in and out of the body - both sensory and motoric (and it even becomes hard to adequately distinguish the two at the subpersonal level). (See Susan Hurley's Consciousness in Action for an excellent exploration of the relation between personal-level phenomena such as visual consciousness, and subpersonal dynamically 'loopy' (from organism to world and back again) phenomena such as sensory and motor behaviour.) Far from our own movements constituting some kind of problem for the otherwise happy receipt of information about the world which we can read straight off the retinae, they are rather the very stuff of perception itself.


Perhaps I am getting carried away attributing these views to Frith? Well, consider the following (p. 102):

Our brain can use this prediction to make us perceive the world as stable even though the image of the world is jumping around on our retina as we move our eyes. This illusion of stability is important for our survival. ... visual changes caused by our own movements are of no relevance ... By predicting these unimportant changes of sensation, the brain can suppress our response to them.


Yet there is no 'illusion of stability' - the world really is stable in such instances. And it is not as if we could perceive perfectly well if we were completely still if we had no predictive machinery. The making of such 'predictions' by the brain is part of the very possibility of our perceptual experience of the world itself, not a mere stabilising factor without which everything would appear to move all the time. Without these 'predictions' we could not be said to have visual experience at all. A material condition of the very possibility of genuine visual consciousness of the world has been read by Frith as if it were instead a mere correcting facilty for the stabilisation of visual images.

Tuesday, 22 January 2008

Making up the Mind 6: Frith's Homuncularism


Part 2, Chapter 4, of Chris Frith's book starts with the following:

Everything we know about the physical world, including what we know about our own bodies, comes through our brain. In the first part of this book I have shown that our brain does not simply transmit knowledge to us like a passive TV set. Our brain actively creates pictures of the world. We know how creative the brain is because sometimes these pictures of the world can be completely false. This discovery is shocking because it makes us wonder how we can ever know whether what our brain tells us about the world is true. The surprise is that our brain ever gets things right. The brain creates its pictures of the world from the very limited and imperfect signals provided by our senses. For example, the visual image on our retina is in two dimensions only and yet our brain creates for us a vivid experience of a world of objects arranged in three-dimensional space. Thankfully, 99 times out of 100 the pictures our brain creates about the world are correct.

What I have been arguing in these posts is that Frith's book presents data to us which is designed to support these astonishing statements and conclusions, but that what is surprising and apparently in need of explanation comes rather from tacit and unwarranted philosophical commitments built into the theoretical structures used to interpret them.

The principle conceptual confusion inscribed in the heart of Frith's work is what, following Anthony Kenny, I have called the homunculus fallacy. This fallacy occurs when, in trying to explain the neurophysiological structures causally necessary for a person to be able to see, one supposes that these structures mediate the act of perception, such that the real perceptual act occurs after the neurological structures have done their work. On this conception real perception - visual presence itself - becomes a kind of inner act: the brain carefully prepares, cooks and then serves up inner representations of the outer world, and the person who is now a kind of detached inner witness of these inner representations is now restricted to only having direct contact with inner pictures.

Now if I really thought this was true, I suspect I would kill myself. Never to be able to actually make contact with my friends, to touch them, to see the world around me, to directly act on and count myself as part of the world: what an intolerably miserable life that would be. Rather than actively making love, for example, I am to understand myself as merely on the receiving end of a variety of sensory impressions dished up by my cortex. Further, Frith is surely right about the following. If he is right about the general form of the relation between mind and brain, then we really would start to 'wonder how we can ever know whether what our brain tells us about the world is true'.

In fact things are surely worse than this. On his picture there seems to be no way of even understanding how we could even conceive of the 'outer world' at all. If all we see are inner 'pictures', then how would we ever come up with the idea of a world beyond these pictures? Why would we think they represented anything? How would the idea of representation come about? How would I know that there was anyone other than myself in this world? In fact, how would I ever be able to conceive of the very idea of other people, or of the idea of a genus of people of which I am an instance? Rampant scepticism seems completely in order, and, even worse, the very intelligibility of our everyday conceptual scheme about physical objects and other people seems completely in doubt.

Frith's homuncularism is of course very evident in the passage cited above. 'Everything we know ... comes through our brain'. But, well, this isn't true. We don't stand on the receiving end of our brain. Rather, our brain is a part of the human being which we are. The neurological processes in question are the mechanisms of perception itself, not mechanisms which provide for an image which then needs to be further seen (but this time with an 'inner eye' or with 'consciousness'). Our capacity to see is instantiated in these neurophysiological mechanisms which support it; the mechanisms are not anterior to the true act of consciousness, and our perception accordingly does not come through the brain.

'Our brain actively creates pictures of the world.' Well - what would be the point of that? Who is there to look at these pictures? Human beings create pictures of the world - occasionally. They hang on walls or moulder in cupboards. Brains, as far as I know, have never spontaneously created any images. And if my brain were to produce a picture, I can imagine that someone else might be able to see it - perhaps if my head was cut open; I myself, however, have yet to witness anything which has occurred in my own skull.

Frith's textbook conceptual confusion is best portrayed in the final two sentences. It is supposed that 3D vision is made possible because the brain processes the 2D image on the retina and adds in the requisite depth. But this is deeply confused. It is not as if perception would instead be 2D if not for this processing, since we are never looking at images on the retinae, but rather at 3D objects in the world. It is only if we theoretically presuppose that we are somehow on the receiving end of processed inputs from the visual system that we would ever come to suppose that the brain needs to do work in order to preserve the depth of the world which is not visually present on the retinal image. Our brain does not 'create for us' our experiences, since our experiences are typically not created. My experience is my contact with the object. It is not that this contact occurs externally to myself, and I am restricted to contact with images that have been created for us. My experience is rather made possible by, grounded in, causally realised in, the various optical and neurophysiological structures occuring in me and extending between me and the object.

On Clinical Practice

In a previous post (What is Clinical Psychology?) I tried to articulate the logos - the essential nature - of clinical psychology. Here I argued that what makes the clinical psychologist distinct (from the counsellor or psychotherapist) is not their plethora of models or investigative or therapeutic skills, but rather the general stance they take. And this stance can be characterised as one which provides for the possibility of combining an empathic engagement with the client with an external perspective on their difficulties. This external perspective allows the clinician to comprehend the client's distress from without rather than within. It notices what it is that is framing the client's distress.

The client's world is constrained by this frame, and so they are not able to see it, nor notice the possibilities that obtain outside of it. The psychologist's job, however, is very much to notice it, and to gradually enable the client to foreground what had previously been background. In an existential-phenomenological idiom, we may say that the psychologist's aim is to take the structure of the 'clearing', or take the 'atmosphere', and bring it itself into view in a wider clearing, or to condense out of the atmosphere distinct visibilia.

I briefly described in the previous post ways in which different (behavioural, third-wave-CBT, narrative, etc.) therapies, as conducted by clinical psychologists, can be seen as fulfiling this 'externalising' aim. However I didn't yet describe what I take to be the relation between theory and therapeutic practice. Here I want to take issue with, rather than attempt to articulate an implicit logos of, mainstream forms of clinical psychologist. For it seems to me that they are generally somewhat arrogant, imposing and intellectualising.

Let me own up straight away: What I am largely reacting against now is what memory provides me of versions of my own former self. Having finished three years of clinical training and two years of personal therapy, I'm in a position to look back at the encounters I had with others, and to wonder about what it was that was, or wasn't, therapeutic in what I brought to these relationships.

And what I've come to doubt is the value of my own attempts to implement, as it were, the formulations of the client's distress I derived. The typical model is: assess, develop a psychological formulation of the client's difficulties, and then develop an intervention based on this formulation. The therapeutic interaction conceived thus is a kind of targeted intervention where the solution is designed to fit the problem.

One way in which this disturbs me is if I start to imagine that this was what was going on for my own therapist in relation to me for the last two years. Did I want my difficulties to be formulated, and to have an intervention targeted at them? Or isn't this really rather disturbing? For one thing it seems to leave me, the agent and the subject, rather out of the picture. It also completely leaves out the live subjective moment in the session and the real value of the relationship itself. None of this is to say that I didn't want to be understood. Being understood, offered acknowledgement, regarded - to have my own self-understanding heard and encouraged, sometimes sensitively questioned - seemed to be what was important. This enabled me to come to new understandings and new insights. The therapeutic journey was of course joint, but it was me that was 'in' therapy, and to this extent the journey and the discoveries on the journey were principally mine.

Carl Rogers

This largely leaves behind the psychologist's 'intervention'. (The very word should be enough to make us suspicious...) But what of the formulation, what of the clinician's understanding of the difficulties and the relationship this understanding bears to the practice. Here I want to suggest a quite different relationship between understanding and practice. I shall call the relationship I want to promote a 'negative' relationship, and the one I want to demote a 'positive' one.

In a 'negative' relationship the clinician's externalising understanding need not directly drive their practice. Rather it has a preventative function. It prevents them from getting caught up in the implicit world- or -self- view contained in their client's talk and action. It enables them to maintain their independence, it helps them to withstand the impact of the client's projective identifications. It enables them to continue to think about what the client brings. And as such it enables them to maintain their distance from the client's difficulties.

I want to make it clear that I am not advocating an emotional distance from, or a kind of objectivising coldness towards, the client. That is not to the point at all. The relevant form of distance here is one which actually enables me to hear the client. Unless I am able to experience them as distinct from myself, to hold onto the differences between us, and the differences between the way they are currently viewing their situation, and the way that others without the client's emotional difficulties may view the client's situation, I will not be able to be in any genuine relationship with the client. It is precisely this distance that enables me to keep an open, listening, relating, empathic, regarding, stance towards them.

Without an understanding of what is troubling the client, they will either remain opaque to me, or I risk becoming identified with them. In the one case I am 'external' to them in a non-comprehending way. As such I am useless to them, except perhaps temporarily as a sounding board, or to fulfil a phantasised function of 'being a psychologist' that they may have. In the other case my empathic identification has stopped me being able to think for them; their 'frame' or 'clearing' or 'atmosphere' has become my own, and I can no longer do the work of helping them to arrive at a different perspective.

By maintaining that kind of distance that enables me to be in a genuine relationship, however, I am able to function as an other for the client. They can test out their understandings of relationships and feelings with me. They can themselves come to see the subtle yet pervasive disturbances that have constructed their emotional relationships to their parents, partners, bodies, feelings, bosses, friends and colleagues. They can trust in my understanding enough to allow themselves to risk new emotional learning, exposure and response prevention, mastery of new tasks, taking of new risks, inhabiting of new and at first uncomfortable feeling states.

I have not yet seen any good critiques of Lambert's view that 40% of the variance in psychotherapy outcomes is due to extratherapeutic factors, 30% to the therapeutic relationship, 15% to technical factors, and 15% to expectancy. (Lambert, M. (1992). Implications of outcome research for psychotherapy integration. In J. Norcross & J. Goldstein (Eds.), Handbook of Psychotherapy Integration (pp. 94–129). New York: Basic Books.) To relate this to the above discussion, it would appear that what the clinician brings by way of capacity to relate to the client may be twice as important as the technical strategies they attempt to implement.

It is striking, then, that clinical psychological trainings - which attempt to train clinicians to bring psychological understanding to bear upon therapeutic relationships - typically stress the ways in which such knowledge can affect the interventions offered by the clinician. They propose a 'positive' rather than a 'negative' view of the relationship between understanding and practice. If Lambert's metanalytic research is on the right lines, and if Rogers' research on the value of the relationship is also to be trusted, and if we want to become better clinicians, then it is surely important to spend our time training clinicians to be able to enter into better relationships. To become more accepting, open, genuine, honest, listening, empathic, etc. in the clinical encounter. And to use their clinical knowledge of the client's difficulties not to try to change the client, but rather to 'keep the channel open' - i.e. to remain able to carry on listening and relating and understanding even in the face of the client's psychopathology. To keep the frame in sight. To not get lost in the foggy atmosphere in which the problem resides.

Sunday, 20 January 2008

Making up the Mind 5: Voluntary Action and the Brain



Exposition

In chapter 3 of 'Making up the Mind', Chris Frith aims to tell us that we 'do not have privileged access to knowledge about [our] own body.' Here are just some of the phenomena he describes to arrive at this conclusion:


  1. Marc Jeanerod's experiments that demonstrate that, if our arm is hidden from our vision, and if we are asked to move it in order make a pointer move straight ahead on the screen, and if a computer has introduced a distortion into our movement such that the pointer deviates to the right when we move it, then we may take it that we move our arm straight ahead to get the pointer to move straight ahead even when we have had to move it somewhat to the right.

  2. Benjamin Libet's controversial experiment in which someone is asked to lift a finger whenever he or she felt the urge to do so, and to report when they feel this urge. Libet found that a change in brain activity occurred at 500ms before the action, and that the urge was reported at 200ms before the finger was lifted. 'Our experience of making a choice at that moment is therefore an illusion'.

  3. How, if you ask me to grab a target, and if you then subtly move the target when I am trying to grab it, I may automatically adjust the movement of my arm, but may not be aware of doing this. 'your brain notices that the target has moved and your brain alters the movement your hand is making so that you can reach the new target position. And all this can happen without you noticing anything.'

  4. The Roelofs illusion: I sit in the dark; you present a lit dot in a lit frame. Then you show it again but have secretly moved the frame (but not the dot) to the right (relative to me). If asked I say 'The target moved left', but not mention a frame movement. But if you instead you ask me to touch the point where the dot was, I touch the correct point on the screen. 'So [my] hand "knows" that the target has not moved even though you think it has.'

  5. p. 69: 'These observations show that your body can interact with the world perfectly well even though you don't know what your body is doing and also when what you know about the world is wrong. Your brain may be directly connected to your body, but the knowledge that your brain gives you about the state of your body seems to be as indirect as the knowledge it gives you about the outside world.'

  6. Phantom limb phenomena.

  7. Cases of anosognosia.

  8. Anarchic hand syndrome

Critique

To an imaginary critic who says 'But I know what I am trying to do. And I know when I'm doing it', Frith replies '"I know if feels like that ... But this is an illusion"'. He cites Daniel Wegner's book The Illusion of Conscious Will, who proposes that we have 'no direct knowledge of our actions. All we know is that we have the intention to act, and then, a little later, the action occurs. We infer that our intention caused the action.'

On the back cover of Frith's book, the neurologist Ramachandran writes of how 'Making up the Mind is a fascinating guided tour through the elusive interface between mind and brain...' It is the way in which Frith handles this interface which troubles me. For a tacitly homuncular conception of the relation of the person to the brain seems to be inscribed in the very way he describes all of the experiments and results he cites. On this view, we have a conscious personality on the receiving end of the functioning of the brain, and the acting body also on the receiving end of the brain's 'decisions' and 'inferences'. We take it that we are the ones in control of our actions, but actually, da dah, it is the brain. Consciousness, it turns out, may be nothing other than a spandrel. Frith presents his findings as if the conception of the mind as surprisingly uninvolved with the real neurological and physical goings on was something that dropped out of, rather than constrained the description of, the phenomena.

I shall now explain what I mean by this. If I want to know whether someone is aware of some change in their environment, then I might watch them, or I might listen to what they are sincerely saying. Usually, in non-microscopic (as it were) time frames, and with no brain damage, there is little dissociation between the two; that is, they tend to go together. However at times there is a dissocation. Neuropsychologists including Frith have shown themselves to be excellent at finding such interesting dissociations.

If such dissociation was the norm it is perhaps unlikely that we would have the concepts we do. They depend, as Wittgenstein suggests, on a certain regularity in the presentation of facts. Typically however the dissociations are uncommon. There is a 'unity' to our various verbal and non-verbal reactions. What the data under-determine, however, is the decision to call the one set of reactions 'unconscious' when they occur in the absence of the other, and the other set of reactions a function of 'consciousness'. All that we really have are dissociations between verbal and behavioural responses to the world. Nothing in this justifies the conclusion that in the one set of cases only the brain 'knows' things, whereas in the other set of cases it is 'we ourselves' who know things. In both cases, to the extent that talk of knowledge rather than, say, know-how is appropriate, it is we that know or do not know. Sometimes only some of the marks of knowledge are present, and it may be difficult to know what to say. What I know I definitely do not want to say, however, is that in such cases it is only my brain that 'knows'. That mereological fallacy obscures, rather than aptly describes, the facts and the conceptual situation in question.

What is the evidence that Frith subscribes to the homunculus / inner agent view of the relation between mind and brain? For one thing, we have his constant use of phrases like 'you don't know what your body is doing, but your body 'knows' this or that...'. The assumption seems to be that I am something other than my body. Perhaps I am a consciousness sitting somehow behind the brain, awaiting on any signals about the body or world it deigns to pass my way. (p. 70: 'The knowledge that your brain gives you about the state of your body...')

For another, he describes the Libet experiment as showing (p. 67) that 'We think we are making a choice when, in fact, our brain has already made the choice'. But, like, our brain is part of us, surely, not some other merely physiological quasi-agent to which we are hooked up. Further, what qualifies our action as chosen are a range of contextual factors (what I say about it, whether my finger moves with or without external aid, etc.) which have little to do with immediately causal antecedents. Self-directed action is not action behind which an inner self sits as a kind of director. In the relevant sense we are our bodies, we are not (and do not pre-theoretically take ourselves to be) their inner captains.

Tuesday, 15 January 2008

Making up the Mind 4: Summary


So let's summarise the results of the discussion so far. First, Frith tells us that he can use the 'big science' of brain scanners to provide an objective check on the goings on within minds otherwise inaccessible to us other than by putatively scientifically untrustworthy first-person reports. We saw, however, that this strategy cannot work: for the brain scanners to provide information about the mind, we must rely on correlations drawn up between the information from the scans, and what the scannees tell us.

Next, Frith tells us that the neuropsychological findings he cites provide evidence for the following idea: that we are not in truth in direct perceptual contact with the world, and that the brain presents to consciousness a picture of the world but disguises all the unconscious inferences that have gone in to making it up. Cases of illusion and hallucination and brain damage are cited to make this case. I have argued, however, that the neuropsychological facts force no such conclusion on us. The conclusion is drawn because of the way the facts have been presented. And they have been presented under the conceptual spell of three inter-related metaphysical pictures:

  1. Objectifying fallacy: Instances of our intentional relatedness (in the sense of 'replete with intentional directedness', not in the sense of 'intended') to the world - in perception or thought, for example - are re-described as if they are mental objects or inner events or states.

    An intentional act of seeing of a plant pot now becomes an inner representation, a kind of mental object. Cases of illusion or hallucination are described as cases in which we are presented only with mental objects, rather than cases in which intentional relatedness fails - as if to say, when it seems to me that I see something but don't, there must nevertheless be something that I see!

  2. Mereological fallacy: Intentional, psychological, properties are attributed to a mere part of the human being, albeit a very important part: the brain. The central nervous system is credited with a range of human abilities such as recognition, inference-making, knowing, representing, etc. These however are properties and abilities that are surely only really sensibly attributed to agents, people, subjects. Often it is clear that the attribution of the human powers, e.g. of representation, is metaphorical and the metaphor can be legitimately cashed out in properly neurophysiological terms. However at other times the brain is described as if it were a competing agent with the person who's brain it is, descriptions which give rise an un-earnt sense of mystery.

  3. Homuncular fallacy: The person, who's consciousness of the world would normally be taken to consist in their perceptual relation to it, now becomes an interior witness of the 'inner representations' (objectifying fallacy) arrived at and served up by the brain (mereological fallacy). Consciousness itself - a kind of inner powerpoiont presentation with the brain at the 'change slide' controls - now inevitably becomes a complete mystery.

As a result of these conceptual confusions we arrive at a situation which is even worse than Frith suggests - that we do not have direct contact with the world. Taken together, these three fallacies provide a kind of triple alienation of the living human being from their immediate environment and from other people. We might have thought that when I am conscious of a flowerpot, I am in a direct intentional relation to it:

Perceiving Subject <----> Perceived Object

But no. First the nervous system is (mereologically...) taken as the proximal subject of experience. This then serves up (entifed...) representations into a kind of inner mind space or consciousness. The (homuncular...) person or self must then resort to perusing the contents of this inner space in order to satisfy themselves with whatever remnants of the idea of a perceptual contact with a flowerpot are left there.

Inner Perceiving Subject ----> Inner Representation <---- Brain Inferences <---- Sensory Stimulation

As a general scheme for explaining human experience this is clearly a disaster. Not only is it founded on three highly dubious metaphysical pictures. It also leaves completely un-understood our capacity to enjoy visual consciousness itself. Our natural consciousness of the world around us becomes internalised into a mysterious inner process. It becomes so mysterious that Frith will tell us in the Epilogue that the book is just 'not about consciousness'. This is perhaps unsurprising. If the business of guiding action and generally getting around the place and staying safe can all be carried out by the right hand-side of the above schematic - i.e. by the brain processes:

Inner Representation <---- Brain Inferences <---- Sensory Stimulation

then what serious role is there left for the inner perceiving subject who becomes somehow aware of what is served up by the brain:

Perceiving Subject --->

If, instead of supposing that human consciousness occurs at the inner end of a host of neurological processing of objectified psychological entities, we supposed that human consciousness just is our intentional relatedness to the world, then we will be free to see the neurological processes and sensory stimulations as part of its realisation or implementation.

Sunday, 13 January 2008

Making up the Mind 3: What the brain 'knows'


So, still following up an earlier post, I'm working my way philosophically through Chris Frith's latest book: Making up the Mind. In this post I'll consider: Frith's attribution of psychological properties to the brain in chapters 1 and 2; his account of the neurological cause of hallucinatory experience in chapter 1; and in particular his rather curious theory that 'Even if all our senses are intact and our brain is functioning normally, we do not have direct access to the physical world. It may feel as if we have direct access, but this is an illusion created by our brain' in chapter 2. To spoil the story before I begin: I'll be suggesting that Frith's (strictly incoherent) attribution of psychological properties to a brain rather than a person (Hacker's 'mereological fallacy') is not always a big problem in itself. We can often cash out the metaphors. The impetus behind the bizzarre propositions of the 'our direct access to the physical world is an illusion created by our brain' sort is instead principally provided by the colluding, tacitly 'homunculuar', view that the mind or self or consciousness lies on the receiving end, as a kind of inner witness, of deliverances of neurological processes. Strike out the confused metaphysics, including that which without warrant 'objectifies' mentality (intentional relations to the environment redescribed as a domain of inner objects), and the neuropsychological facts are seen to warrant only a far more mundane description and to carry no such striking epistemological implications as Frith's text would have us believe.

Chapter 1 aims to show us how a 'damaged brain doesn't just prevent us from finding out about the world. It can also create in our minds an experience of the world that is entirely false'. I doubt anyone would be surprised at the idea that brain damage might lead to hallucination or illusion, so I shan't spend much time looking at the chapter's findings. What I want to do first are to note the colluding force of the 'mereological', 'homuncular' and 'objectifying' conceptual fallacies in the text.


Mereological, Homuncular, and Objectifying (M, H & O) fallacies:


p. 21: 'Just like a video recorder, our eyes and ears pick up information about the physical world and transmit it to our minds'. (H: minds receiving information. M: parts of bodies picking up information.)


p. 22. 'infomation from my eye (and ear and tongue, etc.) goes to my brain'. (as above)


p. 23. 'Light strikes the sensory receptors in my eye causing the receptors to send messages to brain'. (as above)


p. 23. 'Then the activity in the brain somehow creates the experience of color and shape in my mind. This mechanism is not understood at all.' (H: person is on the receiving end of a neurological process of information organisation. Unsurprisingly this mythical process has not yet been understood by science...)


p. 23. 'my mind can have no knowledge about the physical world that isn't somehow represented in the brain. [Footnote: Neurophysiologists often talk of activity in neurons "representing" something outside in the physical world. For example, neurons can be found that only become active when the eye is stimulated by red light. Activity in such a neuron is said to represent the color red.]' (Whilst it is of course people and not 'minds' that have knowledge, and whilst the brain doesn't strictly represent anything, Frith's footnote shows how he is at times aware of the metaphorical nature of such talk of 'representations in the brain'. Unfortunately this awareness does not seem to pervade the rest of the text...)


p. 26. In the 'waterfall illusion...which we can all experience, objects stay in the same place from one moment to the next, but we still see movement'. (O: of course we don't actually see movement, since nothing moves; rather it seems to us that we see movement. If however we start to imagine that seeing is actually being presented with mental objects called representations or perceptions or sensations, rather than with real things like waterfalls, then we can understand the temptation to say 'we see movement' when we only imagine movement. Frith aims to show that the neuropsychological science forces on us the opinion that 'we have no direct connection to the world'; it soon becomes clear however that this lack of connection is a function of the O, H & M conceptual fallacies which are built in anterior to the descriptions of the empirical data.)


p. 27 'Such people [as a brain-damaged man who was able to learn skills (procedural memory) whilst having chronically impaired episodic memory of the situations in which they were learnt (a bit like my own relation to my own first few years of learning to eat and talk)] show that our brain can know things about the world that our mind does not know.' (M: But why map the psychological notions of the episodic and procedural memory of persons onto the functioning of their parts (knowledge in the brain = procedural; knowledge in the mind = episodic)? Surely it is only this arbitrary decision to describe events in this unwarranted way that encourages the unusual conclusion that we and our brains are somehow at epistemic odds with one another.)


pp. 28-29 Blindsight (an ability of some people with particular neurological damage to guess correctly about the movement of objects light from which is stimulating the optic nerve, despite their taking themselves to be unable to see the objects in question) is said to involve 'my mind [having] absolutely no visual content and yet my brain [knowing] things about the visual world and [enabling] me to make accurate "guesses" about that visual world. (H: Again, I am not on the receiving end of a selection of my own brain processes; these processes do not deliver, and hence do not fail or only covertly provide, me, or my mind, with information.)


p. 29 Sub-heading: 'When the Brain Tells Lies' (M: the brain does not strictly speaking represent or misrepresent the environment. Frith had noted this correctly in a previous footnote, but now the metaphor gets lost and it is implied that the brain may tell lies.)


p. 29. 'Sometimes brain damage can cause the mind to have information about the physical world that is completely false.' (H: Mind on the receiving end of possibly damaged brain processes which are then thought of as not passing on the right information.)


p. 29. 'A deaf old lady was woken up in the middle of the night by loud music. ... Eventually she realized that the music was only in her mind.' (O: So she wasn't actually woken up by loud music. She rather awoke to a hallucination of loud music. The objectifying metaphors: placing stimuli within or before the mind where they are now perceived, start to collude with the homuncular conception of the person or mind as only in an immediate perceptual relation to this inner space.)

p. 31. 'How the Brain creates False Knowledge' (The bizarre phrase 'false knowledge' (presumably Frith means false belief?) seems to betray the fact of the unargued conceptual severing of psychological relations to the world (relations such as knowledge) even in cases where these relations are obviously constitutive of the concept (something must be true if we know it, otherwise we only believe it).)

p. 31. 'There are now many studies demonstrating that activity in the brain can create a false experience of something happening in the outside world.' (O & H: A 'false experience...' = can cause it to seem to a subject that they are experiencing something... Once experiences are turned into inner objects to be presented to an even-more-inner subject, then we will soon become only immediately aware of true or false experiences which accurately or inaccurately represent the outer world .... can we already start to see Frith's suposedly psychological conclusions falling out of the conceptual sleights of hand?)


p. 36. After considering electrical stimulation of the brain, epileptic auras, and lsd trips, Frith reports that 'I have to conclude that if my brain was damaged or its function was interfered with by electrical stimulation or drugs Iwould have to be very cautious about the knowledge I acquired about the physical world. Some kinds of knowledge who no longer be available. Some kinds of knowledge might be false and bear no relationship to the real physical world.' (O & H: Knowledge has now become not my 'openness' to the world, as Heidegger might say, not my capacity to act and think in the light of the facts, but a purely internal or mental state of affairs.)

pp. 36-37. 'Checking the reality of our experience'. (H: Once the subject is put in the epistemic predicament of being on the receiving end of the deliverances of their neurological systems, rather than in contact with the world, then it will hardly be surprising that they will seem to be faced with the possibly insuperable and definitely unenviable task of distinguishing between inner representations that have real, outer causes, and inner representations that represent neurological dysfunction.)

p. 41. By considering reaction time experiments, Helmholtz 'realised that various processes must be occurring in the brain before a representation of the an object in the outside world appears in the mind. He proposed that perception of the world was not direct, but relies on 'unconscious inferences'.' (O, H. To be sure, we are not instantly aware of changes in the external environment, and much of this lag has to do with the time taken for the brain to (metaphorically) process (metaphorical) information. But these facts don't force on us the idea that, at the end of this processing, there is some presentation of a representation by the neurological processes to the mind where it appears, nor warrants talk of 'unconscious inferences' in the brain. That description adds nothing to the facts.)

p. 43-44 Various experiments are taken to show that the putative 'experience we have of immediate and complete access to the visual scene in front of us is false. .. Many parts of the scene remain blurred and lacking in detail.' (H: Again we have the brain's putative knowledge of only small details of the visual field, along with its unconscious 'inferences' about much of it, contrasted with the perceptual fantasies that are supposedly 'in the mind'. But there's no warrant in the data for this description. As an aside - it seems to me, on the basis of my own visual experience, that 'my mind' doesn't (i.e.: I do not) experience the world as all equally completely clear. Rather what I am very directly looking at is clear, and so long as I don't cheat by looking about the place, my inability to clearly see the rest of the visual field is obvious. )

p. 49. Visual illusions are taken to demonstrate that 'my brain continues to show me false information even when I know that the information is false and even when I know what the object really looks like'. (H: My brain does not present me with information. I do not exist somehow posterior to my own brain! A natural description is: Frith is amazed that visual illusions persist even when we know they are illusions. Why not just say this?)

p. 60 'In this chapter I have shown that even an ordinary, healthy brain does not always give us a true picture of the world. Because we have no direct connection to the physical world around us, our brains have to make inferences abou that world on the basis of the crude sensations they receive from our eyes, ears, and all the other sense organs. These inferences can be wrong. Furthermore there are all sorts of things that our brains know that never reach our conscious minds.' (H, O, M: What would this conclusion read like if we removed the confused metaphysics and epistemology? How about this: 'In this chapter I have described instances of illusion and hallucination and limited perception in people with healthy perceptual systems. Furthermore I have described cases in which parts of the brain which make possible our recognition of emotion may be stimulated by visual stimuli even when we have no reportable visual experience of the emotional stimulus.' (I have left out the second and third sentences, since there seems nothing left when we remove the conceptual confusions.) Now it seems clear that the first sentence refers to some fairly mundane facts of little interest: we all know already that hallucination and illusion etc. occur in the healthy. What gave the facts the appearance of interest was the 'brain provides or plays tricks on the homuncular mind with only a selection of the details' conceptual mythologising. The final sentence however seems to report a psychological finding of genuine interest and novelty value, a finding which needs no support from the confused epistemology and metaphysics in which it is couched.)

Thursday, 10 January 2008

Making up the Mind 2: 'Can Big Science Save Soft Science?'


So, following up an earlier post, I'm working my way philosophically through Chris Frith's latest book: Making up the Mind.

The Prologue of Frith's book sets out the following argument. (I reconstruct):

1) When you have a subjective experience such as a visual illusion, this only occurs 'in your mind'. (Frith likes to use objectifying metaphors such as the following: if I experience a visual illusion of moving dots, then the 'movement is only happening in my mind'.) 'The only way I can know about the things in your mind is because you tell me about them.' ... 'there is no way I can get into your mind and check ... your experience'.

2) But this seems to be a problem for the psychologist who wants to be considered a proper scientist. As scientist's we don't like to have to go on people's subjective say-so. We want to be able to check. (Frith asks of a synaesthetic friend: 'why should I believe her when she says these are direct sensory experiences that she cannot control?') And scientific psychologists also want to be able to objectively measure the mind. 'there are... properties of the mind that are common to us all. It is these fundamental properties that psychologists are trying to discover.' Frith is confident that 'in time, psychologists will have discovered what to measure and ... developed the instruments ... to make these measurements very precisely'. But, he considers in passing, perhaps this confidence is misplaced, since we cannot check up on the subjective reports of others. How do we know if the subjective experiences are the same for everyone?

3) Thankfully, 'big science' - PET and fMRI scans - comes to the rescue. We can look to see what is happening in people's brains at the very moment that they report their subjective experiences. The 'problem with psychology is solved. We no longer need to worry about these soft, subjective accounts of mental life. We can make hard, objective measurements of brain activity instead.'

But here's the problem: What licenses the inferences from what I see in the scanner to what is going on in the person's mind? If 1) genuinely does represent some kind of a problem in need of a solution, then it had better not be that the solution (brain scans) depend on correlations between what is scanned and the say-so of the scannees about what they are imagining. After all, it is precisely this testimony that I'm not supposed to be relying on - and it is precisely by turning to the 'hard science' of brain scans that I am supposed to be able to avoid having to rely on what the scannee says.

But perhaps here's a way out. Frith tells us that he and a few of his colleagues have 'always been ... interested in the brain activity associated with purely mental events. We have found that when a volunteer imagines he is pressing a button, then the same brain areas become active as when he is really pressing a button. If we had no brain scanner, there would be absolutely no objective sign that our volunteer was imagining pressing a button. ... We assume that he is following our instructions to imagine that he is pressing the button every time he hears the signal.'

Maybe it is this, then, that licenses the inference from scanner result to subjective goings on. We know for sure when a person is really pressing a button. We don't know, aside from by relying in a putatively un-scientific manner on his say-so, when he is merely imagining that he is pressing a button. However when we put him in the scanner we find some part of the brain that lights up both when he is really button-pressing, and when he is merely imagining it.

Doesn't this solve the problem? I think not, and here's why. The 'big science' here is still only as good as the 'soft science' on which it is still based. Someone is pressing the button: parts A, B, C, & D of their brain always light up when they do. For someone else not actually pressing the button, parts C & D of their brain sometimes light up, or perhaps it's parts B & C. How do I know whether this second person is imagining pressing the button? I'm not allowed to ask them, since this would be to submit to the perils of soft science. Nor can I just say that "to have parts C & D light up without A & B just is to imagine pressing a button", since that amounts to tacitly changing the subject - from psychology to neurology. In truth there's no answer to the question given the constraints. If I want to find out whether sole B & C firing, or C & D firing, is correlated with imaginary button-pushing, I have to ask the scannee. Big science bottoms out in subjective testimony after all.

None of this is to say that, if we were worried that someone was tricking us about what they were imagining, and if we had already done lots of scans of trustworthy people imagining that they were button-pressing, and found what the consistent neural correlates of button-press-imagining were, then we might not want to resort to scanning them. But this isn't a case of 'big science saving soft science'. It wasn't because of fears of trickery that the psychologist hoped to be able to rely on brain scanners - to take a 'direct look' into the brain of the putative imaginer. It was because of some supposed scientific illegitimacy in relying on personal and hence 'subjective' testimony that the big science was being brought in.

For my own money, I'm not in the slightest worried that psychological science relies on testimony. That would only seem to be a problem if we took seriously the objectivising metaphors of the mind as a kind of inner place to which we only have access in our own case. If we ignored our Wittgensteinian or Rylean lessons and took those seriously, and if we thought of science as the objective exploration of worlds ('outer' or 'inner'), then we might want to try to avail ourselves of an apparatus (it would preferably be a mind scanner, but it seems that we have to settle for a brain scanner) to have a direct, independent, scout around in there. The problem with that is as described above: We still rely on testimony to make the inferences from brain to mind: our new neuropsychological science of the imagination is still soft at heart.

Take the metaphors less seriously, however, and we may be less inclined to feel disastrously external to one another. Perhaps, for example, much of the time my words directly avow or express my 'mental states' and 'mental processes' - rather than constituting my testimony, i.e. rather than constituting avowals or expressions of merely subjective beliefs, about what I find by way of goings on in my mind. And perhaps in those instances in which I do report rather than avow or express what I am inwardly doing - for example, instances such as imagining pressing a button - then my sincere say-so can be thought of as criterial, rather than merely empirical evidence, for what is thereby reported. Absent reasons to doubt it when you tell me what you're fantasying, and I need no help from big science scanners, telepathy, or God to come to the relevant conclusion: it just drops out deductively.