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New summaries and reviews of papers, articles, books etc.

1.) The World in Your Head - Steven Lehar - added 1 March 2010 (under Neuroscience 4) - Argues against the concept of the brain as a conventional computer.

2.) Indeterminism in neurobiology - Weber, M. - added 22 February 2010 (under Mainstream 15) - Climbs the wrong mountain in associating quantum consciousness with chance events.

3.) Consciousness: Creeping up on the Hard Problem - Jeffrey Gray - added 17 February 2010 (under Mainstream 15) - Criticises functionalism from a mainstream point of view

4.) QUANTUM COHERENCE IN PROTEIN AT ROOM TEMPERATURE
Coherently wired light-harvesting in photosynthetic marine algae at ambient temperature - Elisabetta Collini, Cathy Wong, Krystyna Wilk, Paul Curmi, Paul Brumer & Gregory Scholes - added 8 February (under Protein&coherence 2) - Collini demonstrates quantum coherence in photosynthetic protein at room temperature undermining a key argument against quantum consciousness.

5.) A model of ionic wave propagation along microtubules - Satiric, M. et al - added 5 February 2010 (under Danko Georgiev 2) - Further model for possible basis of quantum information processing in microtubules

6.) Coherence in stable microtubules - Danko Georgiev - added 3 February 2010 (under Danko Georgiev 2) - Discusses computation in microtubules in relation to the electric field and elastic energy in the microtubule lattice

7.) Solving the binding problem: cellular adhesive molecules and their control of the cortical quantum entangled network - Danko Georgiev - added 27 January 2010 (under Danko Georgiev 2) - Proposal for quantum coherence extending between neurons via the synaptic cleft.

8.) Neuroligins and neurexins - Thomas Sudhof - added 22 January 2010 (under Danko Georgiev 2) - Relates to ideas on coherence between neurons

Other recent reviews:-
1.) Neurophysics of consciousness - John, E. - added 2 Feb 2010 (under General Articles 4) (2.) Consciousness not yet explained - Tallis, R. - added 23 Jan 2010 (under Philosophy 3) (3.) Molecular biology and biophysics of microtubules - Georgiev, D. et al - added 13 Jan 2010 (under Danko Georgiev 2) (4.) Why physicalism entails panpsychism - Strawson, G. - added 10 Jan 2010 (under Other Quantum 5) (5.) Dissipationless waves for information transfer in neurobiology - Georgiev, D. - added 6 Jan 2010 (under Danko Georgiev 2) (6.) Consciousness - Revonsuo, A. - added 2 Jan 2010 (under Mainstream 14) (7.) On the dynamic timescale of mind-brain interaction - Georgiev, D. - added 23 Dec 09 (under Danko Georgiev) (8.) Electric and magnetic fields inside neurons - Georgiev, D. - added 21 Dec 09 (under Danko Georgiev) (9.) Analysis of quantum decoherence in the brain - Georgiev, D. - added 15 Dec 09 (under Danko Georgiev) (10.) Mental causation: Libet & Soon - Batthyany, A. - Dec 09 (under Freewill 4).) (11.) Synaptic Self - Le Doux, J. - added 4 Dec 09 (under Neuroscience 3) (12.) Examination of quantum coherence in a photosynthetic system at physiological temperature - added 27 Nov 09 (under Protein&Coherence 2) (13.) Seeing Red - Humphery, N. - added 19 Nov 09 (under Mainstream 13) (14.) Brain Coherence and Entanglement in the 21st Century - added 12 Nov. 09 (under Protein&coherence 2) (15.) Falsification of Hameroff-Penrose model of consciousness - Georgiev, D. - added 5 Nov. 09 (under Other Quantum 4) (16.) Penrose's Godelian argument - Feferman, S. - added 3 Nov. 09 (under Penrose & Hameroff 8) (17.) Godel's First Incompleteness Theorem - added 30 Oct. 09 (under Penrose & Hameroff 8) (18.) The Illusion of Conscious Will - Wegner, D. - added 23 Oct. 09 (under Mainstream 12) (19.) Conditions for coherent vibrations in the cytoskeleton - Pokorny, J. - added 4 Oct. 09 (under Protein&Coherence) (20.) The Root of Thought - Koob, A. - added 3 Oct. 09 (under Neuroscience 3)

1.)

The World in Your Head: A Gestalt View of the Mechanism of Conscious Experience

Steven Lehar, Schepens Eye Research Institute

Lawrence Erlbaum (2003)

INTRODUCTION: Lehar makes a good case against the computer/AI model of the brain, by highlighting the inability of computers to differentiate the edges needed to construct a model of the world, from the mass of less important input. He contrasts this with the ability of biological vision to deduce information from very flimsy inputs. The Gestalt methods suggested for achieving what the brain can do are not entirely convincing, as a means of sorting the mass of data input, and thus avoiding the combinatorial explosions implied by the requirements of visual perceptions. In this respect, a quantum computing approach might look to have a greater chance of success. Further to this, a weakness of the book is the lack of much attempt to relate what is proposed to the physical components and processing of the brain.

Lehar approaches consciousness from the angle of the relationship between visual image processing and artificial intelligence (AI). A computer has all the data relative to an image in the form of numerical data. However, turning this into usable information in AI/robotics has proved an intractable problem. Computers can detect features such as edges, but the problem is that they can detect too many of such features. Their edge detection includes details of texture, surface fragmentation and shadows, but fails to pick out those edges that are relevant for the outlines or volumes of an object. Further, there is no apparent algorithm to deal with occluded objects, where a small object obstructs the view of part of a larger object, but it can be deduced that the larger object continues behind the smaller object. This is taken to mean that the information of global significance for understanding the image is not available in the local edges.

Computers have problems with the spatial structure of visual scenes, and as a result difficulty in navigating in an environment of irregular forms, which, by contrast, present little problem for biological vision. Lehar points out that the retinal image is two-dimensional, but is perceived as three-dimensional, and that therefore the three-dimensional depth of the image must be the result of cortical processing. A basic function of visual perception is argued to be the transformation from a two-dimensional retinal image to a three-dimensional perception in the brain. Apart from inserting spatial structure into an initially two-dimensional image, the brain must also decompose this image into coherent objects with volume within the spatial structure. From this it is argued that the brain must operate a spatial algorithm, in order to produce this three-dimensional image. What computers have had difficulty in achieving is not receiving the visual data, but in developing the sort of processing that allows the brain to turn this data into a conscious image.

The literature relative to these problems concentrates on restricted domains, with separate algorithms for extracting shape from shading, for motion or for lines. However, the problem of dealing with shape of the conformation of objects that reflect light has remained largely unresolved. This divergence in relative performance is argued to show that the basis of biological and computer vision are very different from one another.

Conscious images: Lehar takes the view that the conscious image is assembled in the brain, in response to data from the external world. This is described as 'indirect realism,' in contrast to 'direct realism' or 'naive realism', in which it is believed that we perceive the external world as it actually is. The author thinks that discussions in neuroscience are often implicitly based on direct realism, but he argues that this view is based on false assumptions. The visual experience is at odds with scientific reality, because the subjective world is experienced, as if it were outside the brain, whereas visual processing occurs inside the brain. The causal chain of vision is one, in which the brain can only process material that has already been picked up by the sensory organs. Consciousness is therefore necessarily confined to the experience of internally constructed models. Lehar goes back to Kant, who distinguishes between the 'nouminal' world of light signals etc. and the phenomenal world of internal conscious perception. The 'nouminal' world is only perceived within the phenomenal world.

The author argues that the properties of subjective experience are inconsistent with the present neuroscientific thinking, based on the semi-independent sequential operation of billions of individual neurons. In contrast, our experience is mainly of stable and solid volumes, rather than billions of abstract features. The author accuses the neuroscientific community of evading this problem by assuming the 'naive realism' view, and ignoring subjective experience. This attitude is partly blamed on the mid-twentieth century advent of single-cell recording, which shifted the emphasis from assembly-wide features towards single-cell features. In the same period, the digital computer became a major part of technology, and was seen as an analogy of the brain. At this stage, AI researchers thought that they had the problem of vision solved, and that they could implement robotic vision without paying any attention to biological systems.

Famous Dalmatian: The author discusses the well-known picture of a Dalmatian dog against a speckled background. Much of the dog is missing, and some of the edges that are there are locally indistinguishable from the background. Much of the edge of the dog is missing and some of the edges that are there are locally indistinguishable from the background. The main point about this is that the local information does not allow the observer to distinguish the dog from the background, but when the picture is viewed as a whole, the dog is clearly distinguishable. Lehar argues that this indicates that perception is based on global brain activity, rather than the sequential processing of individual neurons. He claims that no algorithm has ever come close to handling the ambiguity of the Dalmatian dog picture. Furthermore, the picture is viewed as demonstrating, in exaggerated fashion, the principles that underlie biological visual processing. One argument tries to evade this conclusion, by suggesting that an image such as this is a special case that does not apply to normal visual processing. However, Lehar counters that studies that restrict the view of pictures to just a few edges show that humans cannot distinguish between edges that are important to the outline or form of objects, and edges that are just texture or shadows.

Kaniza triangle: Lehar discusses visual figures, such as the Kaniza triangle, where the mind automatically perceives a triangle, although all that is physically there on the printed paper is three black Pacman features. Thus, the observer perceives edges and a brighter white ground than the surrounding area, where neither exists on the paper. Again, this is argued to be a global processing of the image, rather than derived from the examination of individual edges.

Rubin vase/faces: The same is true of other well-known examples such as the Rubin face/vase illusion. A black figure on a page may be perceived, as either a vase or the profiles of two faces opposite one another. The brain jumps from one perception to the other, without ever offering a hybrid picture, and can as quickly reverse its perception. It is argued from this that visual recognition is not the result of feed-forward processing of a visual input leading to a perceptual output, as is often assumed in computer models of the brain, but instead involves a dynamic process that is not completely stable. P. Invariant perception: Lehar also discusses the problem of the invariance of our perception of objects, in that they can be recognised from different angles and in different lights, as the same objects, in a way that is not easily achievable by the analysis of individual edges. Conventional computing could only manage this by having a detector for each possible position, which could produce a combinatorial explosion or NP hard problem, where classical computing might only resolve the problem in a time that was longer than the life of the universe. There have been suggestions that local elements of the object are first recognised, and later put together, but this does not take into account instances, where what are actually different elements may form an image of the same object.

Visual agnosia: The distinction between being able to detect individual features, and gaining a practically useful model of the world can also be demonstrated from human pathology in the form of visual agnosia. There are two forms of this; in a condition known as apperceptive agnosia, the patient can see individual objects, but cannot integrate these features into a spatially coherent three-dimensional whole. The opposite condition is associative agnosia agnosia, where the patient perceives a coherent world, but cannot identify individual objects. This medical finding is argued to contradict the 'naive realism' claim that the brain is just seeing what is out in the world, in which case the whole spatial environment should be perceived.

Gestalt theory attempts to solve the problem of visual recognition by parallel processing, in which the solutions to each part of the visual recognition problem depend on one another, and thus constrain the possible solutions for one another, thus closing in on a single solution. Lehar also proposes the idea of 'harmonic resonance'. This involves resonance between different modules in the brain, with resonance ultimately being communicated to all the relevant systems in the brain. This is seen as a solution to the 'binding problem' or an explanation of the unity of different modalities in conscious experience. This of course relates to the EEG recordings of gamma frequency synchrony in the brain.

Conclusion: It is not clear that these Gestalt proposals involve sufficient processing capacity to overcome the likely combinatorial explosions/NP hard problems implied by perception. Lehar does relatively little to link his ideas to the physical components and processing of the brain. From the look of it, a quantum computing process would have more chance of bridging the gap between classical computing capacity and the requirements of visual perception as highlighted by Lehar.

2.)

Indeterminism in Neurobiology

Weber, M.

philsci-archive (2005)

This paper is really an example of something which is all two frequent in consciousness studies, where a researcher makes an assumption about what is being proposed in quantum consciousness theories, and proceeds to attack what has been assumed without making contact with any real theories of quantum consciousness.

Weber's paper essentially addresses the wrong problem. He is mainly discussing whether the overall development of the universe and within it of large biological structures is influenced by chance events, as a result of wave function collapses at the quantum level.

Unfortunately, this debate is of little interest in respect to quantum consciousness. Early on in his first book, Penrose pointed out that the randomness of the wave function collapse was of little use to mathematical understanding. It was from here that he went on to propose the idea of objective reduction, which is hypothesised to give access to the geometry of spacetime. Weber's search for chance events in the brain is irrelevant to Penrose's and other versions of quantum consciousness theory.

Weber adopts what is essentially the Tegmark approach to quantum coherence in biological matter, arguing that biological systems are macroscopic, interact with the environment, and by implication therefore decohere and behave in a classical/deterministic manner. This paper was written before Engel et al (2007) and Collini et al (2010) demonstrated the existence of quantum coherence in some proteins, and the latter of the two papers demonstrated coherence at room temperature. However, even when the paper was published in 2005, a discussion of Hameroff's proposals for shielding microtubule protein from decoherence would have seemed relevant.

Another unusual feature is the treatment of the possibility of chance events at the synaptic level. This is not in fact a proposition made by Penrose/Hameroff, where dendritic gap junctions are the focus of attention, but given that it is discussed, it is very surprising that Weber does not mention the fact that only 15-30% of axon potentials result in the synapse firing. However, Danko Georgiev, who is critical of the Hameroff model, has recently proposed that neurotransmitter release could be influenced by coherence extending from microtubules via presynaptic scaffold proteins.

Weber also discusses randomness in ion channels, and here too, it is surprising that he does not refer to the work of Gustav Bernroider, who seeks to demonstrate coherence within ion channels and possibly entanglement between them. Bernroider was sympathetic to David Bohm's idea of an implicate order, but it seems possible that his ion coherence could be linked into a Penrose type theory.

3.)

Consciousness: Creeping up on the hard problem

Jeffrey Gray

Oxford University Press (2004)

INTRODUCTION: This book is worth reading for a number of interesting areas of discussion. It attempts to use aspects of synaesthesia to refute the still dominant functionalist theory of consciousness. It argues that intentionality or meaning arises from unconscious processing, and also that there is no true representation of the external world in the brain. Because of these last two points, it is argued that much of the philosophical baggage of consciousness studies can be left behind, and discussion of consciousness should be focused purely on qualia. Gray does not think we yet have an explanation for qualia. He takes the possibility of quantum consciousness, at least in the Penrose form more seriously than most mainstream investigators, although he argues that it contains no explanation for the selection of particular qualia. He sees conscious as being selected for by evolution, because it is causal, but causal in a sense that does not involve agency or freewill. Unconscious systems are claimed to respond to conscious perception, but only in the sense that our brains can respond to a sketch as a reminder, with the sketch having no agency of its own. This part of the discussion seems rather incomplete. Gray has relatively little to say about cognitive processing, the conscious emotional aspects of the brain, or the relationship between these two, which is known to be crucial in determining preferences for action and behaviour.

Gray stresses that conscious experience has no scientifically understood links with neuroscience or behavioural science. Without such links, there can be no understanding of the interaction of consciousness with the physical world. Neuroscience has built up a detailed knowledge of neurons, but this is viewed here as having made no contribution at all to explaining consciousness. Most neuroscience experimentation has not been aimed at understanding consciousness, but at understanding the movement of energy in the brain. Biology as such makes do with two systems, firstly the laws of physics and chemistry, and secondly feedback mechanisms that respond to a variable, which is being controlled. In fact, neuroscience has created a complete outline of brain processing without involving consciousness. There is nothing for consciousness to do within conventional neuroscience, and the existence of consciousness is something of an embarrassment to the theory. But Gray argues that while experimentation has shown much of what we perceive to be an illusion, we should hold onto the fact of conscious experience, for without conscious experience, it would be impossible to have an illusion in the first place. The unconscious mind is argued not to be capable of having an illusion, but only of making an error. In contrasts to an error, an illusion continues even when it is known to be an illusion. Thus knowing that a film is a series of frames does not prevent us from seeing it as continuous.

Refuting functionalism: Gray goes on to discuss functionalism, which he views as the dominant form of consciousness theory. According to functionalism, consciousness is the nature of certain complex systems, regardless of whether they are is made of neurons, silicon chips or some other material. The underlying tissues or machinery is irrelevant. Further to that, consciousness relates only to functions performed by the brain or other system, and does not arise as a result of anything that is non-functional. In looking at the qualia red and green, functionalism says that all that exists are responses, by which the individual's behaviour demonstrates the capacity to discriminate between red and green. For any discriminated difference in qualia, there must be a difference in function. It is also claimed that for every discriminated difference in function, there is a difference in qualia.

Gray claims to refute functionalism, on the basis of data from research into synaesthesia performed at the Institute of Psychiatry in London. In discussing this question further, Gray looks at synaesthesia, where modalities become mixed, as when numbers or sounds are experienced with colour. Extensive experimentation in recent years has demonstrated that synaesthesia is a real and observable brain state, and is most likely the consequence of abnormal projections into the V4 colour region of the visual cortex from other parts of the brain. Brain scanning studies showed that when words were spoken, in addition to the normal activity in the auditory cortex, the V4 colour vision area in the visual cortex became active, in a way which did not occur in normal subjects. There was no related activation in V1 or V2, the earlier stages of the visual pathway. The conclusion drawn from a whole series of experimentation was that the 'word-colour' type of synaesthete has an abnormal projection from the auditory cortex into the visual cortex causing the V4 colour area to produce consciousness of colour. However, there is no evidence that this colour sensation has any function. Thus, there is no relationship between the occurrence of the synaesthete's colour experiences and the linguistic function that triggers them. Gray argues that this phenomena refutes the functionalist theory's analysis of conscious experience.

Intentionality and the unconscious brain: Gray argues that a large proportion of the brain's activity is unconscious. Consciousness is commonly estimated to lag about 250 milliseconds behind an event being registered by the sense organs, but much action and behaviour takes place more rapidly than this. He also discusses the existence of separate systems for conscious and unconscious processing. This is the case in the visual system, where there is a ventral stream that underlies conscious perception, and a dorsal stream that underlies rapid but unconscious actions.

Conscious experience or more specifically the contents of consciousness are usually about something, and this is described as 'intentionality', whereas movements of energy in the brain are just themselves, and are not about anything. Intentionality is another aspect of the 'binding problem', as to how the different modalities, such as sight and hearing, are bound together into a single conscious experience. Gray points out that without binding, eating a banana could involve seeing yellow, feeling a surface and tasting something without the unifying awareness of a particular object known as a banana. Intentionality can also be referred to as meaning, the meaning of the yellow colour etc. is a banana. Without this binding, things would be just meaningless shapes, edges, colours etc. Consciousness appears to arise where modalities come together. This also involves the idea of categories that usually bridge two or more modalities, as with the example of the banana, as a particular category of object.

Gray sees the unconscious brain as containing subsystems that can be regarded as what he calls servomechanisms dedicated to controlling a particular variable, such as the distance between a hand and an object that is going to be grasped. These servomechanisms are often linked to actions. In contrast, conscious perception can be just about perception, such as looking at a sunset.

Despite this distinction, Gray argues that intentionality is based on unconscious processing. The processing in the visual cortex that underlies conscious perception is not itself conscious. Instead, the perception springs into consciousness fully-formed, including the intentionality of what the perception is, or is about. To prove this point, Gray use the example of pictures that can be either of two things, such a duck or a rabbit. They are never hybrid, but are always completely duck or completely rabbit. The perception of a duck or rabbit is argued to be constructed unconsciously up to the last moment. The actual process of binding, as in the binding problem, is also suggested to be an unconscious result of synchronous firing within and between brain regions. Gray's conclusion from this part of his discussion is that intentionality arises from the physical and chemical structure of the brain, but also that if intentionality can be constructed out of unconscious processing, it is unlikely to produce a solution to the 'hard problem' of how consciousness arises.

Representation: Gray goes on to discuss the question of the representation of the external world in the brain. First of all, he reminds us that the external world is nothing like what it appears like in conscious perception. The external world is bits of energy fluctuating in the vacuum, with none of the qualities of solidity, colour etc. attributed to the perceived world. But the author goes further than this. He dismisses what he calls the fall back position, which is to think that the perception of something, a cow for example, is a representation, in the sense of resembling the cow as it really exists. Gray argues that our only direct knowledge of the cow is a brain state. We have has no direct knowledge of the cow as it really is, and it is therefore meaningless to argue that the cow brain-state is a representation of the real cow.

Gray argues the conscious perceptions should be treated as signals. Signals have no need to resemble the thing about which they communicate. A whistle might warn thieves of the approach of a policeman, but a whistle is nothing like a policeman. Perceptual experiences are seen as signals, about what observers might expect about their environment. However, he stresses that these perceptual signals arise in the brain, and do not have any kind of external existence. This is not to say that we cannot deduce useful information about the real world from perception. Thus for example visual perception is a good guide to the reflectance of surfaces, which in turn often has survival value for an organism. Thus there is a 'fit' between the external world and the model constructed in the brain, otherwise we would not have much success in interacting with the world.

Gray also emphasises that conscious perception is not voluntary. Perceptions just pop into consciousness, and are argued here to come from unconscious processing. Furthermore, it is claimed that only a tiny proportion of the data that could potentially enter consciousness actually does. It is possible to distinguish between two types of unconscious processing. Firstly, processing that can never come into consciousness, and secondly processing which is potentially conscious but remains unconscious.

Philosophical Baggage: Gray's message is that we can dispense with much of the philosophical baggage of modern consciousness studies, as regards intentionality and representation, because these are either unconscious or non-existent. Given the reams that have been written on these subjects, and the meagre gains in our understanding of consciousness, many might be glad to dispense with this baggage train. Instead, Gray says we should concentrate on the qualia of subjective conscious experience, as the only aspect of the brain that involves consciousness.

Function of consciousness as comparator and late detector: Gray views the function of consciousness as a 'late error detector'. The brain is argued to be a 'comparator' system that predicts what should happen and detects departures from that prediction. It is suggested that consciousness is particularly concerned with novelty or error. It is also viewed as something that causes us to review past actions, and to learn from errors in these actions. Late error detection permits more successful adaption, if a similar situation emerges in the future. Gray looks at the question of pain. We remove our hands from a hot surface before consciously feeling the pain of touching it. The pain involves is argued to be a rehearsal of the action that led to it, and has the survival advantage of making a repetition of the damaging action less likely.

Gray accepts that there are many unconscious systems that detect errors, so this on its own does not produce a survival value for consciousness. However, he distinguishes consciousness as being multi-modal, and as directing us towards whatever is most novel within several modalities. The brain takes account of plans as to what to do next, plus memories of past regularities, in assessing what is likely to be the next stage of a particular process. These predictions are submitted to a comparator, but still at an unconscious stage. Only the unexpected outcomes, or feedback for the continuation of motor action enters consciousness. We are only conscious of things that change unexpectedly, or things that are particularly important at the moment.

Gray views the function of consciousness as the construction of relatively constant perceptions from ever-changing sensory inputs. The trick is the transmutation of the ever-changing into the constant. The survival value of consciousness is seen as the ability to take a second look, where actions or predictions have gone wrong. The actual detection of departure from prediction is argued to be at the unconscious level, and the perception of error then just jumps into consciousness.

The perceptual system is said to construct a relatively stable picture of the external world, against which unconscious processing by the comparator reports expectations, error and change. Experimental data suggests this is useful with navigation. A route once learnt can be re-used without trial and error on the basis of a few major land marks. Similarly in other circumstances such as physical actions, consciousness can act by providing information on key variables, which feed back into action.

Gray goes on to make the distinction between egocentric and allocentric views of the spatial world. The egocentric is concerned with action, and is centred on parts of the body. Conscious perception, however, uses an allocentric system where the relationship between objects is independent of the conscious observer. Damage to the inferior parietal lobule, as in Balint's syndrome, leads to errors in binding together the different features of a single object. This is related to the parietal's involvement with spatial perception, and is taken to suggest that binding requires that objects are attributed to a particular spatial location. Egocentric space is suggested to be unconscious in the parietal lobule, with a projection to the hippocampus, which supports conscious allocentric space.

Medium of display: Gray regards consciousness as a medium of display created by unconscious processing. The standard objection to this is that it creates an infinite regress because there has to be a conscious homunculus viewing the display in the Cartesian theatre, and then an homunculus within that homunculus and so on ad infinitum. However, Gray argues that the conscious display is used by unconscious systems, as in the example of unconscious aversion to a food associated with a gastric illness. Conscious perception is in this theory created by unconscious systems, and used by other unconscious systems to respond to late errors, unexpectedness or novelty.

Consciousness – causal but without agency: Gray likens the conscious perception to a sketch made of a particular scene that is retained for use as a record or reminder of the scene. In this way, the sketch is causal in the sense that it performs the function of recalling or assisting memories, but it is not directly active in the brain. In Gray's consciousness model, the conscious perception plays much the same role as the sketch in his analogy. Consciousness is causal, in the sense that downstream unconscious systems respond to it, mainly in the area of error correction. However, this conscious aspect of the brain has no agency or freewill with which to initiate or inhibit actions, anymore than the sketch on a piece of paper can initiate can initiate actions independently of our brain.

Incompleteness: I think that although there is much of interest in Gray's analysis of intentionality, representation and the unconscious, his analysis is nevertheless incomplete in important ways. In discussing the unconscious nature of rapid response actions, he adopts the conventional but superficial approach to the Libet experiments. When he describes how these showed that trivial (automatic pilot type) actions are initiated in the brain before the awareness of the decision to make the action, he appears to simply assume without further discussion that this must apply to more deliberative or strategic decisions that by their nature takes a longer time to reach a conclusion.

In line with this, he also makes no extended to attempt to discuss either cognitive activity or the impact of emotions, and more importantly the interaction between the prefrontal cognitive areas and the areas of the brain processing emotions. It might be possible to argue there are unconscious systems making the actual decisions in these areas of the brain, but if Gray did want to establish this point, he needed to discuss his model in terms of these systems, which have a central role in determining actions. In particular, he needed to pin down the role of our subjective experience of emotion in determining preferences and actions, if he wanted to justify the dominance of the unconscious in actual decision taking.

What are qualia: Gray poses the question, as to how the brain creates and inspects the display medium of conscious perception. In asking this question, he makes the assumption that consciousness is different from either behaviour or brain activity. He views this as a 'hard problem', in the sense of the term coined by the philosopher, David Chalmers. He considers that for all of biology, except for the question of consciousness, the laws of physics and chemistry, plus natural selection and the internal feedback mechanisms selected for by natural selection are sufficient explanation. He considers that consciousness has sufficient causal effects to justify it being selected for by evolution. The hard problem is seen as being the difficulty of locating consciousness qualia within physics.

Amongst researchers within mainstream neuroscience, Gray is unusual in not finding the idea of quantum states being relevant to neural activity as ridiculous. However, his discussion of the Penrose's version of the theory is not really complete, in that he concentrates entirely on Hameroff's propositions for quantum activity in the brain, rather than Penrose's original reason for looking to the quantum level in the first place. Penrose's suggestion was that a special form of quantum wave reduction was the only thing that could explain mathematical understanding, when it goes further than what can be determined by the axioms of any formal theorem. This might been seen to answer one of Gray's main objections to the theory, which is as to why particular wave function collapses should select for any one particular qualia. Gray also questions the temporal aspect of Hameroff's model, where the proposed 25 milliseconds to wave function collapse equates to the 40 Hz gamma synchrony, which is possibly the best known correlate of consciousness. Gray argues that this does not work very well because it takes at least ten times as long as this for a conscious perception to form. However, this does not seem an insuperable problem given that there is strong support for the idea of a connection between gamma synchrony and consciousness. This is the case even in conventional neuroscience, which suggests some physical link between synchrony and the time to conscious perception, whether at the classical or the quantum level. Gray's final word on the subject is that at least Penrose tries to explain qualia, which is seen as an advance on Dennett and functionalism, which essentially deny the data that we all have as to the existence of conscious experience or qualia, and which any valid theory of consciousness should attempt to explain rather than deny.

4.)

ROOM TEMPERATURE QUANTUM COHERENCE IN PROTEIN

Coherently wired light-harvesting in photosynthetic marine algae at ambient temperatures

Elisabetta Collini, Cathy Wong, Krystyna Wilk, Paul Curmi, Paul Brumer & Gregory Scholes

Universities of Toronto, New South Wales and Padua

Nature, 463, pp. 644-7, 4 February 2010 doi:10.1038/nature08811

INTRODUCTION: This low-key paper may in time come to be seen as one of the decisive studies of the 21st century. The paper shows that room temperature quantum coherence can occur in biological matter. In 2007, Engel et al had shown that coherence was possible in organic matter, but this was only demonstrated at very low temperatures, whereas the Collini study demonstrates similar activity at ambient temperature. The paper and related commentaries makes no mention of consciousness, although a relevance to quantum computing is suggested, which is a possible step towards discussing consciousness. The main plank of the arguments against quantum consciousness relates to the speed of decoherence in biological matter being too quick for coherence to be relevant to processing, particularly neural processing, in such matter. This argument looks to have been substantially undermined by the recent study.

Antenna proteins are an essential part of the photosyntetic process, which absorbs light and transmits the resulting excitation between molecules to a reaction centre. Recent research has concentrated on determining the mechanisms that support a very high level of efficiency in this energy transport. Light-harvesting antennas are comprised of eight pigment-molecules, with different pigments absorbing different frequencies of light. The route the energy takes across the molecule is important in terms of energy efficiency.

Studies have documented the fact that light-absorbing molecules in some photosynthetic proteins transfer energy according to quantum mechanical rather than classical laws even at ambient temperature. This contradicts the 20th century dogma that long-range quantum coherence would always decohere in the temperatures found found in biological systems.

This paper by Collini et al describes X-ray crystallography studies of two types of marine cryptophyte algae that have long-lasting excitation oscillations and correlations and anti-correlations, symptomatic of quantum coherence even at ambient temperature. Distant molecules within the photosynthetic protein are thought to be connected to quantum coherence, and to produce efficient light-harvesting as a result. The cryptophytes can photosynthesise in low-light conditions suggesting a particularly efficient transfer of energy within protein. According to the traditional theory, this would imply only small separation between chromophores, whereas the actual separation is unusually large.

In this study, performed at room temperature, the antenna protein received a laser pulse, which results in a coherent superposition in the protein. The experimental data of the study shows that the superposition persists for 400 femtoseconds and over a distance of 2.5 nanometres. Quantum coherence occurs in a complex mix of quantum interference between electronic resonances, and decoherence caused by interaction with the environment. The authors think that long-lived quantum coherence facilitates efficient energy transfer across protein units.

The authors remains uncertain, as to how quantum coherence can persist for hundreds of femtoseconds in biological matter. One suggestion is that the expected rate of decoherence is slowed by shared or correlated motions in the surrounding environment. Where light-harvesting chromophores are covalently bound to the protein backbone, it is suggested that this may strengthen correlated motions between the chromophores and the protein.

In the same issue of 'Nature' that published Collinis study, the 'News and Views' section of the journal also comments on her paper. It emphasises that this is the first study in which quantum coherence in photosynthetic proteins has been observed at room temperature. It comments on the remarkable efficiency of energy transfer, between the antennas that guide excitation energy from hundreds of light-absorbing pigment molecules towards the subsequent reaction centres that drive biochemical events. Collini is suggesting that quantum coherence could be a factor in this efficiency.

Earlier studies had observed coherent behaviour in green sulphur bacteria, but at very low temperatures. Collini et al observed quantum coherence in the antenna, and found that this persisted over 400 femtoseconds, in contrast to an expectation in traditional theory of only 100 femtoseconds. Coherence was observed between widely separated pigment molecules. This has also been observed in bacterial light-harvesting complexes. However, this was at very low temperatures, while the Collini study was at room temperature. Engel et al, who were responsible for some of the earlier studies, have speculated that quantum coherence allows antennas to search for the lowest energy state of the complex more efficiently, thus enhancing the energy transfer to the reaction centre. Coherence might help excitations to avoid local energy traps or minima, on their way to the reaction centre. Covalent binding to the protein backbone is speculated to make coherence longer lasting.

Perhaps the most surprising aspect of this latest paper on coherence in proteins is the speed with which news of the development has made its way to the level of more popular science, in the form of a useful full page summary by Kate McAlpine in the 'New Scientist'. She mentions that Gregory Engel, who was respnsible for the earlier low temperature studies of coherence in bacterial proteins, is enthusiastic about the Collini result. Engel and his group have also performed a study at 4 degrees centigrade, much above previous levels, although below the 21 degrees of the Collini study. Engel is also quoted as saying that this work could have implications for quantum computing, where a core problem has been to operate at the very low temperatures that are usually thought necessary to prevent quantum decoherence. The speed with which this work has been picked up and given prominence in a popular science magazine suggests a background change of attitude to coherence in protein. The vexed question of quantum consciousness is not mentioned, but the suggestion of activities within protein as a model for quantum computing is moving is in that direction.

5.)

A non-linear model of ionic wave propagation along microtubules

Sataric, M., Tuszynski, J. et al, University of Novi Sad and Cross Cancer Institute

European Biophysical Journal (2009) 38:637-47, DOI 10.1007

The cytoskeleton is a major component of all cells including neurons. It is comprised of actin filaments, intermediate filaments and microtubules, which are comprised of subcomponents of tubulin protein dimers, formed from an alpha and a beta monomer. These structures are organised into networks interconnected by proteins, with specific roles to play in the functioning of the cell. The microtubule is usually formed from 13 protofilaments. Each monomer of the tubulin dimer has a C-terminal helix, plus an amino acid sequence, projecting 4-5 nanometres out from the microtubule, and referred to as a tubulin tail (TT)

These TTs are involved in interaction with motor proteins and with the microtubule associated proteins (MAPs) that cross-link the microtubules. The alpha tubulin monomer TT is 19 amino acids long, with ten negatively charged residues. The TT on the beta monomer is nine amino acids longer. The detailed charge distribution on the tubulin surface results in a peak in electrostatic potential at every protofilament and a trough in the areas between them. The microtubule as a whole is suggested to be a 'cable' conducting 13 parallel ionic flows. The flow of ions along the microtubules is postulated to be mainly channelled through valleys in the electrical potential running parallel to each of the protofilaments. It is suggested that the TTs could significantly influence ionic current flow. The ions are suggested to flow at a radial distance from the surface of the microtubules.

The model proposed here is that microtubules with brush-like tubulin tails and surrounded by solvent ions in the cytosol act as electrical transmission lines. It is suggested that this model could provide some insight into a role for microtubules in information processing within neurons.

6.)

Coherence in stable microtubules

Danko Georgiev, School of Medical Science, Kanazawa University

Neuroquantology, December 2009, vol. 7, 4, pp. 538-47

Stable microtubules comprise a large proportion of neurons, and are the main component of the cytoskeleton, which supports the extended dendritic arborisation and the axons of the neurons. Most neuron microtubules are stabilised by the cross-linking of microtubule associated proteins (MAPs), and the capping of the ends of proteins, both of which suppress frequent assembly and disassembly of the microtubules. This greater stability in neuron microtubules answers the often asked question, as to why non-brain microtubules are not seen as a basis of consciousness. But this does not prevent the non-consciousness of microtubules outside the brain being trundled out as an argument against quantum consciousness.

In dendrites, cross-linking is performed by MAP2 and in axons by MAP-tau. The author argues that the GDP and GTP molecules are not able to provide energy for computation within the microtubule, and energy from their processes is argued to go into the microtubule wall, as a result of the stretching of pre-existing bonds between the tubulin dimer subcomponents in the microtubule lattice. The microtubules are composed of 13 protofilaments. The tubulin subcomponents or dimers are connected by longitudinal bonds within the same protofilament and lateral bonds between dimers in different protofilaments. Here, chemical energy has been transduced into stored elastic energy. The author considers that this stored elastic energy might be important for the microtubular functioning within cells. He suggests that microtubular computation might be driven by interaction between the electric field inside neurons and the charged elastic brain microtubules.

Reference:
Caplow, M. et al - Free energy stored in the microtubule lattice - Journal of Cell Biology, 127, pp. 1918-24

7.)

Solving the binding problem: cellular adhesive molecules and their control of the cortical quantum entangled network

Danko Georgiev, Medical University of Varna

Cogprints: 2 May 2003

INTRODUCTION: The author proposes a model by which quantum coherence arises in the cytoskeleton, is transmitted to the synapse, and from there to neighbouring neurons via the neurexin-neuroligin complex in the synaptic cleft. This is suggested to bring a large group of neurons into quantum entanglement, and to provide a solution for the binding problem.

The article proposes a possible process to support quantum entanglement between neurons, based on neurexin and neuroligin. This involves the 20-30 nanometre wide synaptic cleft, which is filled with electron-dense material. The presynaptic side has an active zone containing vesicles of neurotransmitters. Apart from signalling processes, there is also an adhesive junction at the synapse formed by neurexins and neuroligins. These are brain specific molecules, which bind to one another, and are part of a family of molecules known as CAMS, which are often present at synapses. The author claims growing evidence for the role of CAMs in modulating both short and long lasting plasticity. Receptors required for longer term potentiation (LTP) may be linked to the modulation of the cell adhesion proteins. Adhesion proteins could modulate glutamate receptors, possibly by altering the width of the synaptic cleft, and the size of the pre and post synaptic active zones, and also by altering glial cell processing around the edge of the synapse. Neurexin and neuroligin appear well suited to link pre and postsynaptic signalling mechanisms. The C-termini of neuroligins are inside the postsynaptic neuron and bind to the PDZ, which is thought to act as a nexus for receptors and signalling molecules on the postsynaptic side. The C-termini of the neurexins binds to CASK another PDZ containing protein on the presynaptic side.

The author relates these structures to the proposal that the cytoskeleton is important to the processing of incoming information in the brain, and that macroscopic quantum coherence arises in the cytoskeleton. Beyond this, he is looking for a means by which coherence passes from one neuron to another. He has rejected the Hameroff proposal that this happens via gap junctions between dendrites.

There is a thickening of the cell membrane on both sides of the synapse. The postsynaptic density (PSD) has been proposed to be a protein lattice that organises receptors, ion channels and signalling molecules. The proteins in the lattice contain PDZ domains involving PSD-95 that can bind to many types of synaptic proteins, including receptors for the main excitatory synapse. CASK, a presynaptic protein and PSD-95 stabilise the synapse by interacting with neurexin and neuroligin cell adhesion molecules, or by indirectly linking synaptic proteins to the cytoskeleton. CASK is tethered to the cytoskeleton by an actin binding protein. The author suggests that the neurexin-neuroligin cell adhesion complex could be connected indirectly to the cytoskeleton and mediate interneuronal quantum entanglement across the syanptic cleft. This is suggested to allow coherence across a large group of neurons, as a way of solving the binding problem.

8.)

Neuroligins and neurexins

Thomas Sudhof, Stanford University

Nature, vol. 455, 16 October 2008, doi:10.1038

INTRODUCTION: Although it is not part of Sudhof's article, it has been separately suggested that the neurexin/neuroligin complex could allow quantum coherence that is proposed to arise around microtubules, and might also involve presynaptic scaffold proteins, to pass through the synaptic cleft to subsequent neurons, and thus presumably a whole neuronal assembly. This has been put forward as an alternative to Hameroff's suggestion that coherence is transmitted across a whole neuronal assembly via gap junctions.

Neurexins and neuroligins are cell-adhesion molecules that connect the presynaptic area of one neuron with the postsynaptic area of another, mediate signalling across the synaptic cleft, and specify syanptic functions. The complex is suggested to be important in the maturation of synapses, and in specifying the properties of particular circuits. Studies suggest that neurexin and neuroligin are not, however, essential for synaptic formation, but may be for subsequent maturation and function. Synapses have high plasticity, and changes in them can alter the relative contribution of synapses in a circuit. These changes probably depend on the action of the cell adhesion molecules, neurexin and neuroligin. These molecules probably bind to one another, and interact with proteins within the neurons. Current studies suggest that they mediate signalling between presynaptic and postsynaptic areas. Neurexins come in many isoforms, and it is suggested that these could code for different interactions at the synapses.