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Mainstream 2Mainstream: 2 Further reviews of articles and books relative to mainstream consciousness theory 1.) The Feeling of What Happens - Damasio 2.) What are the Neuronal Correlates of Consciousness? - Crick & Koch 3.) Brainshy - Patricia Churchland 4.) Quantum mechanics in the brain - Koch & Hepp 5.) The Astonishing Hypothesis - Francis Crick - Revisits Crick's seminal book for mainstream consciousness theory The Feeling of What Happens Antonio Damasio ISBN 0 15 100369 6 The most useful function, although not the main purpose of Damasio's latest book, is to lay to rest several of the scientific notions about emotions, language and other aspects of the mind, which had dogged scientific discussion during the 1990s. However, in its central purpose, of discussing consciousness and its relationship to emotion and the self the book proves disappointing. In the first place, the book tends to identify the self and consciousness as being the same thing, rather than treating the self as only a part of the contents of consciousness. The book has very little on the question of the qualia. Damasio was already aware of this criticism of his approach at the time of writing the book, but sidesteps this criticism with the claim that all consciousness can be seen as consciousness with a sense of self. This may true in a sense most of the time, but it does not get round the experience of qualia, such as the colour red, as something external to us and the self. Nor does it deal with altered states of consciousness in which the sense of self is reported to disappear, but something continues to observe. In the end consciousness is argued to arise from the ensemble of brain functions governing the body, but it is not all clear from Damasio's book, how the non-conscious signaling systems involved would make the jump into conscious, and thus gain a property not detected elsewhere in the universe. Consciousness & Language Damasio argues in particular against the popular late 20th century view that consciousness was derived from language. He sees language, comprising words and sentences, as a translation from non-linguistic images that stand for particular entities or events. The original images are seen as having been non-verbal. However there is no image as such for the self or for consciousness, so if these properties were created by language, they would lack the underlying concept of self. Where Damasio studied patients with speech impairments, he found that the basic thought processes were intact, and that the patients' consciousness of their situation seemed no different from anyone else. Language impaired patients could be attentive and purposeful, and could communicate effectively with sign language. There were also indications of emotional responses. Even where there was complete loss of speech, it was possible to maintain sign communication, and there was no indication of lack of consciousness. Consciousness & Memory Damasio further thinks that core consciousness is not based on memory, except in respect of a very brief short term memory. He does not think that core consciousness is based on either longer-term memory or language. Core consciousness is retained even when subjects have major brain deficits. In certain types of amnesia knowledge of both the past and the anticpated future is lost, but core consciousness and a sense of self are retained. The core self is seen as a transient moment-to-moment experience, but the autobiographical self is relatively stable. However, core consciousness is felt to be closely related to both primary and background emotions. Core & Extended Consciousness The other problem of the book could be felt to be the over emphasis on the distinction between core consciousness found in all developed organisms and the extended consciousness of humans. Core consciousness seems to be a property of all reasonably developed organisms. Where core consciousness is disrupted the structures involved are usually near the midline of the brain in both humans and non-humans. While it seems fair to make a distinction between bare awareness of surroundings and the various achievements of humans, both would seem to be a subset of the same hard problem, by which consciousness is an entirely different property from anything in the inanimate world. Emotions Damasio identifies consciousness as the biological function that allows us to be aware of emotions. This is at least an advance of 20th century brain research, which was prone to marginalise the role of the emotions. Damasio's own research has shown that contrary to 20th century views emotion is essential to both reasoning and decision taking. He views consciousness as providing knowledge of suffering, pleasure, embarrassement, pride and in humans, the adaptively important experience of empathy. Damage in the cingulate cortex, for instance, can disrupt both core and extended consciousness and may result in zombie like behaviour. He also argues that our existence of what are effectively zombie states, contrary to Dennett's attempt to prove that these cannot exist. He says that in some unusual states, for instance states related to epilepsy, a subject can be unconscious and not capable of retaining memories but still capable of movement and attention to surrounding objects. Damasio describes himself as having been puzzled as to how the activities of the limbic system, which instantiates the emotions in the brain, came to produce an actual experience for the organism. In principle, the activity in the limbic system and its interaction with the prefrontal could be an entirely non-conscious signalling system, as are many other segments of the brain. He defines six primary emotions, happiness, sadness, fear, surprise or disgust. However, there are also secondary or social emotions such as embarrassement, guilt and pride, and 'background emotions' such as calm or tension. He sees the role of emotion as being to create circumstances advantageous to the organism having the emotions. They are generated from an ensemble of sub-cortical regions, starting with the brain stem, and they both regulate and represent body states. He sees the body as a theatre of the emotions, with emotions regulating internal states in preparation for specific physical reactions. Damasio argues that the emotions are made known or experienced through the sense of self. Therefore, it was important to know how the sense of self was generated. He identifies two aspects of the self, firstly what he calls 'the movie in the brain', and secondly the sense that there is an owner or observer of the movie. He thinks that consciousness and emotion are inseparable in a way that consciousness and wakefulness are not, and points out that impaired consciousness usually results in impaired emotional response. Damasio defines core consciousness as providing a sense of self relative to one moment and one place, the here and now. Extended self, as found in humans, is said to provide a sense of self at a point in the history of an individual and relative to an anticipated future. This autobiographical self corresponds to a collection of unique facts characterising a person and depending on an organised memory. The Body State The body state has to be kept within narrow parameters. The brain governs the body state by detecting small changes in the body's chemical profile, and acting to correct these. The most important components for this control are the brain stem, basal forebrain and hypothalamus. Neural maps signal moment by moment the state of the entire organism. Damasio thinks that the roots of the self are in this ensemble of brain structures that govern the body and in his view at the same time generate the representation of being. Like so much of mainstream consciousness theory there is a quality of wooliness. It is actually not at all clear by what physical process this ensemble of signalling systems in the body would make the essential jump from conscious to non-conscious. Damasio considers that we are not conscious of our feelings, although we tend to view consciousness and feelings as the same sort of thing. He thinks that consciousness is only necessary if feelings are going to influence the subject in the future. Emotion and consciousness are seen as separate although possibly having a common underpinning. Damasio thinks that emotions are part of the process of homeostasis, by which the body maintains its stability. When emotions are actively experienced, the hypothalmus, basal forebrain and brain stem release neurotransmitters in many regions of the brain with important effects, such as pleasant or unpleasant experience. The emotions are mainly located in sub-cortical areas. These include the brain stem, hypothalamus, basal forebrain, PAG and amygdala. In the cortex, the anterior cingulate and the ventromedial prefrontal are important. Different sites process different emotions. Sadness activates the ventromedial prefrontal, hypothalamus and brain stem, which are however not activated by anger. The amygdala is in the depths of the temporal lobe and relates to fear but not disgust or happiness. With an emotional response, two types of message are sent out from the brain region. One route is hormones in the bloodstream that act on receptors in cells and the other is nerve signals. In external pain such as heat, the heat activates thin unmyelinated nerve fibres known as C fibres. This may be experienced as pain, and even if the subject is unconscious, there will be reactions. Work in Damasio's lab has shown emotion to be integral to reasoning and decision taking. This evidence comes from subjects, who displayed normal rationality, until they lost the ability to experience certain emotions as a result of brain damage in the ventral and medial prefrontal and the parietal. These patients could reason logically, but actual decisions were erratic. Reason can be used to control emotions, but reason also needs a degree of emotional input to function properly. Thus contrary to the Dr. Spock image, reasoning for the purpose of action does not benefit from the abscence of emotion. Damasio also showed that feelings could be unconscious. This was based on controlled tests with an amnesiac subject, who had no memory of what he had done on the previous day. He would be introduced at separate times to two researchers, one of whom would involve him in tedious task and the other who would let the patient do what he wanted. The next day, although he had no memory of the individuals involved, he showed a preference for the researcher who had allowed him to do what he wanted. Most images whether remembered or not are considered to carry some emotional charge. The Proto-Self Damasio thinks that the sense of self has a biological precedent in an entity called the proto-self. This is a collection of neural patterns mapping the physical structure of the organism. The proto-self is conceived as emerging from the various activities of the nervous system. A number of brain regions are considered to be necessary to implement the proto-self, including the brain stem nuclei, the hypothalamus, the basal forebrain, the insula and the medial parietal cortex. Damasio envisages that a limited core consciousness arises from the relationship between organism and object, although it is not clear what it is in this relationship that kick starts the move from inanimate information exchange to the different property of conscious awareness. What are the Neuronal Correlates of Consciousness? Francis Crick & Christof Koch In 23 Problems in Systems Neuroscience: Eds. Hemmen, L. & Sejnowski, T. (2006) This represents the last chapter of a 23 chapter volume on current problems in neuroscience. It is interesting to compare the limited ambitions and tentative tone of this chapter with the confident and even hectoring approach of Crick's 1994 book, 'The Astonishing Hypothesis'. Here he suggests on the first page that 'you're nothing but a pack of neurons', thus implying that existing and soon to be revealed neuroscience would dispel the problem of consciousness. This seems to have been a widespread view in neuroscience at the time, but by 2006 it was looking like a disappointed hope. In contrast to the confident, we'll solve it tone of 1994, the 2006 piece decides to limit itself to discussing only the correlates of consciousness, in the hope that identifying these will be a jumping off point for dealing with consciousness. This is an inherently reasonable approach, although there is the caveat that a correlation between two things is quite different the two things being identical. The temptation to say that the correlates, whatever they are, are consciousness, has to be resisted. Moreover, even with the much more limited remit of the 2006 chapter, there is a tentative quality to the approach, which contrasts with the 1994 book. What about Gamma Synchrony Another curious aspect of this chapter, which targets the neural correlates, is its complete silence in respect of the gamma or '40Hz' oscillation in the brain. Crick and Koch were instrumental in promoting this feature as the best available correlate of consciousness in the 1990s. The accusation in some quarters is that Crick and Koch dropped the gamma oscillation, when it was discovered that it correlated to dendritic rather axonal activity, the latter being seen as the key neuronal activity in conventional neuroscience. The authors start the main part of their discussion by raising the problem as to what is the difference between the parts of the brain involved in consciousness and the parts which are not involved. They say that they are not particularly interested in the reticular activating system, but more in those parts of the brain that may be involved with the binding problem and more especially qualia. They are especially interested in where the creation of qualia might be located in the brain. This sounds interesting, but the discussion which follows does not give the reader much to bite on. Attention is intuitively seen as close to consciousness, but not much is known about the mechanisms involved. Some degree of short-term memory is seen as necessary for consciousness, but here again no very specific correlates are suggested. Discussion of evidence drawn from the consequences of brain damage is the most interesting part of the chapter. Local brain damage can remove particular parts of the contents of consciousness, which contrasts oddly with scans indicating the wide distribution of neural activity, for instance visual activity. The evidence suggests that certain parts of the cortex are essential for certain aspects of visual perception, although even in these cases some interaction with other areas is still considered necessary. These essential areas for consciousness of particular properties are speculated to be involved in binding together aspects such as colour, motion and shape. The essential areas are referred to as 'nodes' by the authors. They discuss how the nodes could be constituted, and favour the idea that they could comprise cortical columns of pyramidal cells projecting to other parts of the brain. Crick and Koch end their piece by discussing whether the discovery of the correlates of consciousness would enable them to explain the qualia. They offer the idea of processing many types of information rapidly in a way that expresses the significance of the activity, or what philosophy refers to a intentionality or 'aboutness'. It is not clear how such processing is to achieve such a different result from all the other processing in the brain, and the authors themselves admit the need for a 'bridging principle'. It is not even clear to authors whether such bridging principles can be found within existing science, or whether some theories will have to be reformulated on an informational basis. As a whole. the chapter is clouded by a vagueness and lack of any very clear direction as to a theory of either the correlates of consciousness or consciousness itself. Brainshy: Non-Neural Theories of Conscious Experience Patricia Smith Churchland In: Towards a Science of Consciousness II: The 1996 Tucson Discussions and Debates: Eds Stuart Hameroff, Alfred Kaszniak, Alwyn Scott MIT Press 1998 In this paper Churchland seeks to refute the consciousness approaches of Chalmers and Penrose. With reference to Chalmers, who famously characterised consciousness as the ‘hard problem’, Churchland wishes to show that consciousness is no harder than many other outstanding problems in neuroscience, such as motor control, learning or memory. Churchland seems to mock the idea that consciousness may be a different type of problem from these other neuroscience problems. However, with these other problems there is general agreement that however hard these problems may be, they could in principle be solved by a system of algorithms for manipulating energy, protein and other brain materials. What would emerge is a dynamic not in principle different from other aspects of organisms or even inanimate matter. It is less easy to do with consciousness, because what we know about electricity, about protein and about other brain molecules does not allow for them producing a new property not seen elsewhere in the universe. Churchland further attacks the zombie notion, which is essentially the argument that the brain functions of receiving, processing and responding to data could be achieved without the help of consciousness, and without giving rise to consciousness. Consciousness is indeed absent from the standard neuroscience description of the brain, which is causally closed. Churchland tries to evade this by saying that because we can conceive of such a brain does not necessarily mean that it could exist, and therefore we shouldn’t base anything on this argument. It is certainly true that we don’t know enough about consciousness, to say whether or not humans could have evolved without it. But that does not get us away from the fact that brain processes, as described by current neuroscience, do not have a requirement for consciousness, and do not produce it. Subsequent discoveries may show that the brain processes do require consciousness, but that is not the current state of neuroscience. It is somewhat ironic that the mainstream, which does everything it can to belittle consciousness and still more freewill, rushes to its defence when it is suggested that a sophisticated brain might operate without consciousness. Like other mainstream writers, Churchland seeks to fudge the question of qualia. She admits briefly that there are ‘prototypical’ qualia such as pain or blueness, as in the blueness of the sky, but then dives off into discussing grey areas such as thought or experience of limb positions. She asks whether these qualify as qualia. This proves to be rather a sleight of hand, because she now doubles back on the ‘prototypical’ qualia, and claims that they are only a starting point for investigation and not a full characterisation of their class. In this way, she manages to chip away at the qualia problem by introducing categories that might not be qualia, and thus might lead themselves to easier explanation. Even if this approach was successful in the grey areas, it would still leave the ‘prototypical’ qualia of pain and the blueness of blue unexplained, so really Churchland hasn’t progressed at all, although her readers may be left with the impression that she has. Churchland goes on to give us a bit of a lecture on philosophy, and in particular the fallacy of argument from ignorance. Basically she is saying that ignorance about something does not allow one to draw any conclusions about it. One can only draw a conclusion about oneself, to the effect that one is ignorant about the property under discussion. In particular, it is wrong to draw the conclusion that (1) we can never explain the property, (2) that science can never deepen our knowledge of the property, or (3) that the property can never be explained. Only a few modern thinkers such as Colin McGinn support something like the (1) and (2) positions, so the question is really as to whether the third position stands up. In justifying her stance, Churchland targets some straw men, for instance that because we don’t know the cause of a noise in the night, we are not justified in supposing a supernatural or alien origin, rather than gettinging to grips with the possibility of explaining consciousness from existing science. The difference between Churchland’s noise in the night and theories of consciousness is that we are not as ignorant about biology and physics as we are in the case of the noise in the night. We know enough about these to determine the type of things that are possible with them. A system of algorithms instantiated in neurons could in principle drive other neurons to perform brain processes, such as motor control, learning and memory, the precise mechanism of which is as yet unknown, but we know enough about the components of the brain, to know that they do not produce a property not detected in the rest of the universe, and consciousness falls into this category. Penrose/Hameroff Model The last part of Churchland’s paper deals with the Penrose/Hameroff model. Churchland remarks with truth that the details of the Penrose/Hameroff theory are highly technical. This seems too much for her, and she decides to skate round the main issues, but still attempts to refute the theory. Penrose did invoke the Platonic idea of mathematical truth, but in terms of the theory as a whole, this concept could be seen as only an image for what Penrose is proposing. Churchland, however, makes it look like the centrepiece. Her approach to the core of Penrose’s argument about consciousness, that it requires something that is not based on algorithms that can only be found at the quantum level, is garbled. She states that Penrose requires operations at the quantum level, but does not state why. This has the effect of making the whole thing sound improbable, without her having to engage with Penrose’s arguments. Penrose developed a detailed argument for how quantum gravity might be involved, but instead of trying to refute this, Churchland treats us to throw away lines such as ‘quantum gravity were it to exist’ and ‘no adequate theory of quantum gravity exists.’ Of course, scientific knowledge could never progress at all if every hypothesis was treated like this. Meanwhile Churchland offers no reasoned or detailed refutation of Penrose. We are also told that ‘mathematical logicians generally disagree with Penrose’, but their arguments are not presented, so we have no chance to judge. Churchland attempts to disparage the microtubule part of the Penrose/Hameroff theory. She points out correctly that anaesthetic molecules bind to protein receptors in the cell membrane. However, the evidence appears to suggest that these molecules permeate down to other cell proteins including microtubules, so she has hardly made the case against microtubular consciousness on this basis. Strangely she misses the strongest argument against the theory which is the tendency to rapid quantum decoherence in the conditions of the brain. She make think she is referring to this when she mentions the possibility of coherence being swamped by ‘millivolt signalling’. However, the problem is not signalling as such, but the overall activity of the environment. In fact, since this paper was written, microtubules have been shown to be involved in signalling. Subsequent to this the tone of the article sinks to a rather unprofessional level. Any proposal made by Hameroff is ridiculed for being only a ‘might’, a possibility, but how can science develop without ‘might’ proposals. Churchland also seems to think that the microtubule proposal did not explain how it linked to consciousness. This is factually incorrect, with regard to the detailed work of Penrose and Hameroff. Quantum mechanics in the brain Christof Koch and Klaus Hepp Nature, vol. 440, 30th March 2006 Koch and Hepp produced a surprisingly misleading essay on quantum consciousness in the March 2006 edition of Nature. Unfortunately this essay is all too typical of mainstream writers’ casual approach to quantum consciousness, the assumption presumably being that its not worthy of serious study. The essay is headed by a graphic of the infamous Schrödinger cat paradox, along with a caption claiming that a recently developed thought experiment ‘challenges the idea that a quantum framework is needed to explain consciousness.’ However, it is not until readers are getting towards the end of the two page essay that they discover that the quantum framework that is actually challenged by the experiment is the physicist Wigner’s proposal that it was the consciousness of the observer that collapsed the wave function. Wigner’s idea is not one of the main modern ideas for quantum consciousness, and in fact it is actually not a quantum consciousness theory at all. Wigner proposed that consciousness could collapse the wave function, but he did not advance any theories, either classical or quantum, as to how consciousness arose in the brain. The essay mentions the Penrose/Hameroff model as being the best known approach to quantum consciousness. The surprising thing here is that Penrose’s proposal is the precise opposite of Wigner’s. Whereas, Wigner proposed that consciousness collapses the wave function, Penrose proposed that the wave function collapse gives rise to consciousness. This might seem an easy mistake to make in dealing with esoteric theories, except that Koch has debated the Penrose proposal with Penrose’s collaborator, Stuart Hameroff, and should have been well aware of the nature of their model. This is not the only shortcoming in this essay. The authors repeat the old argument that action potentials along axons and signalling at synapses is on to macroscopic a scale to allow quantum coherence, somehow failing to mention that none of the main quantum theories suggest quantum coherence of this kind. This again, despite the debate with Hameroff on the details of his model. The paragraph arguing that the models for the necessary mathematical operations for perception in the brain are available looks doubtful given the continuing difficulties with artificial intelligence and counter claims that algorithms for perception that are capable of running on classical computers are so far lacking. The Astonishing Hypothesis Francis Crick Simon & Schuster (1994) ISBN 0-671-71158-X It is interesting to revisit a book that was seen as seminal, when it was published in 1994, but is less frequently mentioned now. Crick makes frequent references to his cooperation with Christof Koch, although in contrast to subsequent joint work, Koch is not actually credited as co-author. There is an element of hubris to the title itself, in that in seeking to uphold the mainstream paradigm, to the effect that consciousness can be derived from neuroscience as currently understood, this book is the reverse of astonishing. Rather, it is exactly the point of view that a mainstream theorist would be expected to take. What would have been truly astonishing would have been if Crick had sought an explanation outside of established neuroscience. For astonishment, and in deed fury and ridicule, we need look no further than the response to Penrose’s rather more surprising hypothesis, produced in the same period as Crick’s book. The only hint of the unconventional in this book appears in the first page of the preface, where Crick appears to take a sideswipe at Dennett’s even more hubristically titled ‘Consciousness Explained’ published three years earlier in 1991. Crick remarks that: ‘some philosophers are under the delusion they have already solved the mystery (of consciousness), but to me their explanations do not have the ring of scientific truth.’ The opening lines of the book proper are memorable for their tone of high confidence stating that: ‘The Astonishing hypothesis is that “You”, your joys and your sorrows, your memories and ambitions, your sense of personal identity and freewill, are in fact no more than the behaviour of a vast assembly or nerve cells and their associated molecules. As Lewis Carroll’s Alice might have phrased it: “You’re nothing but a pack of neurons.” It is interesting to contrast the rather domineering tone of these opening lines in 1994, with the cautious approach of a joint article by Crick and Koch published in 2006(1.), which states that: ‘Our strategy is to leave the core of the problem (qualia) on one side for the time being and instead try to discover the minimal neural mechanisms.’ Beyond this, the main surprise of Crick’s 1994 book is that the first 200 or so pages contain very little discussion of consciousness. There is a detailed description of the brain and in particular the visual system, but little attempt to explain how these mechanisms generate consciousness. On pages 7-8 it is rather arbitrarily decided that explanations relative to the brain and neurons do not need to descend below the level of chemical interactions, but there is little discussion as to why this should be so. Crick does not bother with even one of the routine dismissals of quantum consciousness. The proposition does not exist so far as this book is concerned. Brains & computers He does, however, caution against a too simplistic comparison between brains and computers. Computers depend on very fast serial calculations, while brains use relatively slow parallel calculations. This makes brains more resilient than computers, because the loss of a few components from a parallel system is not vital to its function. Further to this neurons have a much less predictable response than computer switches, and can be subject to signals that modulate their behaviour. Crick also take the view that the widely used computer simile of hardware and software is not valid when applied to the brain. He thinks that there is no clear distinction between hardware and software in the brain. He also points out the difference between the number crunching processes, where computers far outstrip humans, and the task of recognising the significance of objects and processes, where computers have tended to struggle. As is the case in much 1990s consciousness literature, a considerable amount of space is devoted to neural net computing. In this period, there were hopes that these could mimic the parallel processing of the brain, but much less has been heard about this type of technology in recent years. Neural correlates of consciousness It is not until p. 207 that Crick starts to look in earnest for the neural correlate of consciousness. He reasons that consciousness is likely to involve some form of attention, and with it some very short-term memory, otherwise there would be no memory of the thing that is being attended to. A problem arises when it is considered that more than object or experience can be attended to. This is the ‘binding problem’ or the problem of the unity of consciousness. Crick points out that in comprehending less familiar objects, the brain must deal with an almost infinite possible combination of features. The Gamma Synchrony Possibly the most interesting part of the book is the discussion as to whether binding could be achieved by the correlated firing of neurons involved in attentional activity. The most striking brain oscillations are the so-called 40 Hz (actually 35-75 Hz) or gamma oscillations, as originally studied by Wolf Singer, Charles Gray and others, shortly before this book was written. It was shown that synchrony could occur between different cortical areas and even between different hemispheres. Singer and Gray suggested that this could be a solution to the binding problem. Crick and Koch were more explicit, suggesting that the attentional mechanism would select an object and synchronise a coalition of neurons relevant to the object of attention. Crick also tried to locate the seat of consciousness in the brain. He suggests that the lower layers (5&6) of the cortex that receive the results of computations in the other layers are a possible site. Pyramidal neurons in layer 5 are seen as prime candidates, because they project outside the cortical layers. Short-term memory input is required for this system to work, and this is suggested to depend on a reverbatory circuit from layer 6 of the cortex to the thalamus and back to layers 4 and 6 of the cortex. The thalamus may also be a location of consciousness in this scheme. Synchronised firing in this system is suggested to be the neural correlate of consciousness. What is lacking in this scheme is any suggestion of what physically different characteristic in the pyramidal neurons or connected neurons in the thalamus gives rise to the distinct qualia and subjective property of consciousness. Crick admits rather in passing that his scheme has not explained the subjective nature of consciousness or the qualia. However, the really disappointing aspect of all this is that the most interesting aspect of this book, the gamma synchrony, was not properly followed up. For a time Crick’s prestige promoted the work started by Singer and Gray. However, the discovery that the synchrony was with the dendritic activity of neurons rather than their axonal spike activity seems to have led to the topic being dropped by the mainstream, leaving Hameroff, who connects gamma synchrony to possible qauntum activity, as its main proponent. Freewill Evaded A book of this kind would not be complete without an attempt to get rid of freewill. In this case, Crick appears to hide behind the screen of unconscious computation. He does assume that he is conscious of his future plans, which to some extent conflict with the Libet readiness potential method of disposing of freewill. However, Crick comments that we are not conscious of the computation involved in deciding our plans. In a sense, this is obviously true in that it is known that a large part of the brain’s activities are unconscious. However, if we consider the complex thinking that can be involved in arriving at a decision, it is apparent that this is very different, from Crick’s implication that a ready made and unconsciously manufactured decision pops out of some kind of slot in the mind. More importantly, although Crick mentions Antonio Damasio, he fails to mention important aspects of his early 1990s work, which strongly argued that the ability to come to decisions, as opposed to merely pondering pros and cons, depends on links between the prefrontal areas of the brain, involved in reasoning, and our experience of emotions and bodily feelings. If this link is broken, as in some forms of brain damage, decision making becomes impossible or refers only to immediate gratification rather than future planning. The important characteristic of emotion and bodily feeling is that they involve qualia or subjectivity, which therefore need to be brought into the processing, computational or otherwise, by which the brain produces decision. In the end, the main significance of this book was the Crick’s prestige made consciousness studies respectable after having been a taboo area during much of the 20th century. References:- 1.) Francis Crick & Christof Koch (2006) - What are the neuronal correlates of consciousness - In: 23 Problems in Systems Neuroscience Eds; van Hemmen, L. & Sejnowski, T. - Oxford University Press ISBN-13: 978-0-19-514822-0 |
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