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

1.)   The influence of dopamine in generating action from motivation  -   Mark Walton, Jerylin Gan & Paul Phillips  -  added 6 February 2012 (under Neuroscience: Dopamine and motivation)

2.) 
Where has your willpower gone  -   Roy Baumeister  -  added 30 January 2012 (under Freewill: Baumeister on freewill)  -  Argues for physical basis of free will

3.) 
Death of the eternal cosmos   -   Lisa Grossman/based mainly on Alexander Vilenkin  -  added 26 January 2012 (under Cosmology: Problems with inflation theory)  -  Discussion of mathematical with inflation theory

4.) 
Despair at popular science presentation of consciousness studies  -  added 25 January 2012 (under Quantum Mind Blog)

5.) 
Persistent dynamic entanglement from classical motion:  How biomolecular machines can generate non-trivial quantum states  -  Guerreschi, G., Cia, J., Popescu, S. & Briegel, H.  -  added 17 January 2012 (under Neuroscience: Test for entanglement)  -  Possibility of testing/falsifying hypothesis of quantum effects in protein

6.)  Can machines be murdered?  -  Tate, M.A. et al  -  added 9 January 2012 (under Neuroscience: Machine consciousness)

7.) 
The quest for animal consciousness  -  Andrea Nani, Clare Eddy & Andrea Cavanna  -  added 6 January 2012 (under Neuroscience: Consciousness and executive function)  -  Studies show consciousness essential to activate executive brain regions.

8.)  Conscious states are a crosstalk mechanism for only a subset of brain processes  -  Ezequiel Morsella & Tiffany Jantz   -   added 4 January 2012 (under Neuroscience: Consciousness as a crosstalk mechanism)  -  Relates to work on both gamma synchrony and orbitofrontal




Further reviews:-
1.) Protophenomena and their physical correlates - MacLennan, B. - 22 Dec (Neuroscience: Protophenomena) (2.) The flexibility of chemosensory preferences - Geraldine Coppin & David Sander - 21 Dec (Neuroscience: Flexibility of preferences) (3.) Predicting emotional reactions: Mechanisms, bias and choice - Sharot, T. - 20 Dec (Neuroscience: Predicting emotional reactions) (4.) The Neurobiology of Preferences - Symmonds, M. & Dolan, R. - 19 Dec (Neurooscience: Neurobiology of preferences) (5.) Decoding subject-driven cognitive states with whole-brain connectivity patterns - Shirer, W - 18 Dec (Quantum Mind Blog) (6.) Quantum boundary - 17 Dec (Quantum Mind Blog) (7.) Quantum biology prospects (2012)  - 16 Dec (Quantum Mind Blog) (8.) Pressure for multiverse orthodoxy - 8 Dec (Quantum Mind Blog) (9.) Importance of what's missing - T. Deacon - 6 Dec (Mainstream: Self-only consciousness) (10.) Implications of anaesthetics  -  added 29 November 2011 (under Neuroscience: Implications of anaesthetics) (11.) Quantum states cannot be interpreted statistically - Pusey, M. et al - 23 Nov (Physics: Quantum reality theorem) (12.) Consciousness v. information - 22 Nov (Neuroscience: Consciousness v. information) (13.) Photons out of empty space - based on Chris Wilson - 21 Nov (Cosmology: Photons out of empty space) (14.)  Answering Descartes: Beyond Turing - Stuart Kauffman - 13 Nov (Physics: Quantum and classical interaction) (15.) Online Book:  Consciousness, Biology & Fundamental Physics - 7 Nov (Online Book 1-6) (16.) Quantum collapse theory - 3 Nov (hysics: Quantum collapse theory) (17.) Independence and connections of pain and suffering - Fink, S.B. - 24 Oct (Neuroscience: Pain and emotional assessment) (18.) Decoding visual inputs from multiple neurons -  Quiroga, Q. - 19 Oct (Neuroscience: Neuronal selectivity and invariance) (19.) Sparse but not 'Grandmother-cell' coding - Quiroga, Q. - 7 Oct (Neuroscience: Neuronal selectivity) (20.) Single-neuron correlates of subjective vision - Kreiman, G., Fried, I., & Koch, C. - 6 Oct (Neuroscience: Single-Neurons and subjective vision)




1.)

The influence of dopamine in generating action from motivation

Mark Walton, Jerylin Gan & Paul Phillips

In:- Neural Basis of Motivational and Cognitive Control  -  MIT Press (2011)

Keywords:  dopamine, midbrain, basal ganglia, nucleus accumbens, opioid neurotransmitters

INTRODUCTION:  The release of dopamine into the striatum and particularly the nucleus accumbens is closely related to the subjective evaluation of sensory inputs, and to the subsequent selection of behaviour and actions.


The authors start by referring to a distinction between the evaluation of reward, and the process of deciding to obtain, and then acting to obtain a reward. It is suggested that much twentieth century research fell short in not paying attention to the internal motivation of subjects. The authors acknowledge that several regions of the brain may be implicated; their emphasis here is concentrated on the striatum, particularly the nucleus accumbens and also dopamine projections.

The dopamine projection to the nucleus accumbens come from the ventral tegmental area (VTA) in the midbrain. Dopamine is a modulatory neurotransmitter often associated with the modulation of the excitatory neurotransmitter, glutamine. There is particularly dense innervation of the striatum by dopamine. Release of dopamine and availability of dopamine receptors in the nucleus accumbens is associated with drug addiction and also with compulsive shopping, eating and gambling.

A good deal of past research has concentrate on the role of dopamine in the selection of isolated rewards, rather than the more realistic situation of subjects assessing competing rewards and associated uncertainty as to the costs and probabilities of obtaining particular rewards. Recent studies, however, point to a correlation between the firing of dopamine neurons and the size and probability of particular rewards. Some studies also suggest a connection between dopamine activity and the timing of future rewards. Dopamine is seen as important in allowing the subject to exert the effort needed to obtain a particular reward. Dopamine release is viewed by the authors as facilitating, but not controlling, responses that seek potentially costly rewards. It is seen as a motivation to seek novel options and potential future rewards.

Evidence suggests that dopamine is involved in signalling the availability of reward. This is partly related to the prediction of reward, but also to actions directed towards gaining rewards. Additionally, the release of dopamine from the VTA can increase the probability of a reward being sought. In situations where there is conditioning, dopamine release can change from being directly related to the arrival of the reward, to being merely something that predicts the future probability of the reward. Dopamine activity can also increase where a reward is either above or below the predicted level, being thus an indicator for error predictions. The authors see dopamine in the nucleus accumbens as being important in making reward predictions when the subject is encountering an uncertain environment. However, this is viewed as only one influence on the subject's actions.




2.)

Where has your willpower gone

Roy Baumeister, Florida State University

New Scientist, 28 January 2012

Keywords: Free will, will power, self control, emotions, neurotransmitters

INTRODUCTION:  It is quite encouraging to find Baumeister writing on free will or self control in a popular science magazine, given that as a psychologist, he is a long way from the mainstream's reliance on a simplistic interpretation of the Libet experiments. Although the article is given a rather reductionist spin, stressing that will power is driven by glucose based energy, its arguments are fatal for the deterministic establishment view as to the non-existence of free will.

In contrast to the mainstream view that there is no such thing as free will, with unconscious and deterministic computations responsible for all human actions and behaviour, Baumeister argues that free will or self control requires energy, and is therefore part of the physical processing of the brain, rather than an illusion as the mainstream would have it. P. Baumeister states that research demonstrates that when subjects have had to exert self control, they perform poorly on a subsequent test of self control. It is argued that energy is depleted by the first exercise of self control leaving less available for the second attempt.

In one such test, subjects were left next to a table with chocolate biscuits, which they were not supposed to eat. Some of the subjects succumbed to temptation and ate the biscuits. Subsequently, both the subjects who had succumbed and those who had resisted attempted a puzzle, which unbeknown to them was unsolvable. Those who had resisted the biscuit temptation gave up sooner on the puzzle, suggesting that their mental energy had been depleted by the effort of resisting temptation.

In this context, will power is compared to a muscle that can tire, although its full energy can return after a period of recuperation. Baumeister proposes that the energy driving will power is ultimately based on glucose that is the basis of neurotransmitters instructing axons to fire. A meta-analysis performed in 2010 showed that as in the tests mentioned earlier, subjects' performance deteriorated between a first and second self control test. However subjects dosed with glucose after the first test performed well on the second test.




3.)

Death of the eternal cosmos

Lisa Grossman/based mainly on Alexander Vilenkin

New Scientist, 14 January 2012

The fashionable theory of eternal inflation at the beginning of the universe has been used to explain both the fine tuning of the laws of nature and to allow for string theory having 10500 solutions.

Alexander Vilenkin of Tufts University has examined the equations relating eternal inflation to the Hubble constant describing the expansion of the universe in Physical Review Letters, DOI: 10,1103/physrevlett.90.151301. The conclusion is that it is impossible to have a spacetime with this property, as the constant has a limit that prevents inflation. The same sort of constraint applies to the idea of cyclic universes going through endless Big Crunches followed by Big Bangs. From this Vilenkin concludes that there is no possibility of a universe that did not have a definite beginning.





4.)

Despair at popular science treatment of consciousness studies

Perhaps we should despair of modern consciousness, studies or at least ban it from appearing in popular magazines. A quarter century on from the lifting of the complete taboo on mentioning consciousness in scientific circles, a popular article in a popular science magazine (which often does good stuff on other subjects) can come over as  a mixture of error, misrepresentation in the early stages, followed by a move to peripheral topics which could never by themselves explain consciousness.

The first part of the article takes the familiar route of looking at Penrose's ideas, and then quickly demonstrating how they are wrong. Except unfortunately that these arguments are also in error. The ancient argument that microtubules can't support consciousness because they are present in all cells in the body and not just neurons is trundled out. While much of consciousness studies is painfully complex, here there is a simple answer, to the effect that microtubules are denser and more stable in neurons, making them more suitable for information processing than the cells in the rest of the body.

Not content with this, the article goes on to make a double misrepresentation as to why quantum consciousness theories are unpopular. The article correctly states that 'almost everyone researching consciousness rejects the quantum computing theory' but misrepresents the reason for this. It is claimed to be because invoking one mystery (quantum theory) to explain another (consciousness) gets you nowhere. This lets down the less well informed reader, for the reason that Penrose never proposed that because quantum theory was a mystery, it was a good basis for explaining another mystery. This was a criticism, or rather just a piece of ridicule coined by the philosopher, David Chalmers, in the 1990s, but tirelessly repeated by the more superficial critics of quantum consciousness. In fairness to mainstream consciousness studies, there are more serious reasons for arguing against quantum consciousness, but these are not touched on in this article.

Another misunderstanding here is the suggestion that Penrose's theory was proposing neural correlates of consciousness, whereas it was proposing the basis of mathematical understanding later extended to cover consciousness itself rather than a correlate, which is simply a feature found in the same times or places as consciousness. There is, an in itself interesting, section on building up knowledge of which brain areas react to which images an actual image of what the brain is looking at. This is a tremendous tour de force technically, but tells us precisely nothing about why these brain activities produce consciousness.

Having whiled away a good deal of space discussing potential correlates of consciousness, the article ends on a curious note. It is suggested that scientists will never find the correlates of consciousness. Why? Because, we are told, there is no difference between conscious and unconscious processing, and as a result the whole idea of consciousness, or possibly just the idea of consciousness being a problem (which of these isn't really clear) is a function of muddled thinking. This seems wrong on first principles, because we know that some systems of activity in the brain are necessary for consciousness, (for instance the global gamma synchrony) and systems of activity lacking this are not conscious. Being conscious is a different for the subject from not being conscious and is produced by different systems of activity (as opposed to specific brain areas referred to in this article), and on this basis it is impossible to refer to the two as being the same.




5.)

Persistent dynamic entanglement from classical motion: How bio-molecular machines can generate non-trivial quantum states

Guerreschi, G., Cai, J., Popescu, S. & Briegel, H., Universities of Innsbruck, Ulm and Bristol

arXiv: 1111.2126v1 [quant-ph] 9 Nov 2011

Keywords:  quantum entanglement, quantum error correction, thermal equilibrium

INTRODUCTION: The authors' model studies the cyclic regeneration of quantum entanglement in hot systems. This looks to open the road to modelling or even experimental simulation that would constitute a possible test for/falsification of non-trivial quantum states in proteins such as those found in neurons.

The paper refers to a simple mechanism by which a molecule forced out of thermal equilibrium by oscillations, can sustain quantum entanglement. This type of entanglement can survive intense noise, but cannot survive if the oscillation ceases. This is argued to be the basis for non-trivial quantum entanglement in biological matter.

The authors remark that this reverses the previous orthodoxy, which held that quantum effects could not exist in biological systems because of the amount of noise in these systems. They note that research in photosynthetic organisms have undermined this case in recent years. The existence of entanglement in a system is seen as greatly increasing information processing capacity, and this underlies the potential of quantum computing. It is pointed out that the previous orthodoxy was based on the assumption of thermal equilibrium, whereas biological systems are open and driven systems far from thermal equilibrium. Such systems are suggested to be capable of quantum error correction that could sustain longer-lived quantum entanglement in biological systems.

In a 2010 paper in Phys Rev E (1.) the authors presented a mechanism by which a molecule subjected to non-thermal equilibrium oscillations could sustain entanglement between two states. This could be maintained despite a level of environmental noise that would not allow entanglement to persist in the absence of non-equilibrium oscillations. Protein molecules, which undergo conformational changes are suggested as the sort of environment in which quantum entanglement of the type found in this model could arise.

In the first section of their paper, the authors look at the possibility of entanglement generated by molecular motion. A biomolecule undergoing conformational change can lead to an interaction between different sites of the molecule. The conformational changes of the molecule can force localised spins to come close or move apart. With the molecular configuration oscillating in a periodic way, cyclic regeneration of entanglement can be sustained over long periods of time, despite noise that would make static entanglement impossible. With thermal equilibrium, entanglement becomes impossible above a certain temperature. The authors, however, ask what happens when molecular motion is involved, and seek to demonstrate that entanglement can keep recurring in an oscillating molecule despite a hot environment.

The authors consider a simple process, with spins that are far apart and with an interaction that is weaker than the surrounding field. In this state, there will be no entanglement. When the spins approach one another entanglement can appear transiently on time scales shorter than that required for thermalisation. The molecule is seen as being kicked out of thermal equilibrium. The generation of entanglement depends on the rate of thermalisation not being too fast. The sustained recurrence of entanglement requires a persistent supply of free energy that can be produced by the conformational changes of the protein. In the author's model the background field predominates when the spins of the particles are widely separated, but when they are close together their interaction predominates. The authors assume that two spins start far apart and are in a state of thermal equilibrium. The spins oscillate, move closer together, are driven out of thermal equilibrium, and entanglement is generated. Environmental noise here drives a persistent and cyclic generation of new entanglement. The periodic oscillations are seen to keep molecules far away from thermal equilibrium, with the continuous change in the shape of the molecule preventing thermalisation.

The authors emphasise the constructive role played by thermalisation. In a hot thermal bath the first oscillation of the molecule is lost more quickly than in a cooler environment. However, the pumping of energy is seen to provide a reset mechanism. In discussing biological systems, the authors consider that chemical interactions would serve to keep the system out of equilibrium. But in gaps between chemical activity, equilibrium could return, and entanglement would therefore be transient.

In summary, the authors say that they have demonstrated that entanglement can recur even in a hot noisy environment. In biological systems this can be related to changes in the conformation of macromolecules. The authors say that this modelling is a route by which to search for the signatures of entanglement in biomolecular systems. They also think that existing technology could provide an experimental simulation of their model. This could possibly amount to a test for/falsification of the hypothesis that non-trivial quantum states act within proteins, and thus test related theories of consciousness.





6.)

Can machines be murdered?

Tate, M.A. et al

Keywords: consciousness, artificial intelligence

INTRODUCTION: This chapter in 'Consciousness and the Universe' emphasises the lack of depth of thinking that can be seen as a hall mark of the functionalist approach to consciousness theory.


The first sentence makes the assumption that particular actions or more especially the combining of particular actions will produce consciousness. Characteristically in this sort of writing, no argument is presented, and conclusions are merely asserted. Computers/robots are making advances in mobility, face recognition and other functions. It is not clear whether the authors think that a machine performing just one of these functions could become conscious. At any rate, their main emphasis appears to be concentrated on generating some magic out of the combination of different modalities that occurs in the brain, although this point isn't really clarified.

Relating consciousness to the combining of modalities has a certain plausibility in respect of recent neuroscience, in that consciousness in the brain is correlated with the global gamma synchrony extending across regionally located modalities. It is possibly awareness of this arrangement in the brain that has suggested that combining a number of functions could produce consciousness, although again this neuroscience background is not discussed or even mentioned.

A general problem relating to this suggestion is that the synchronisation of action spikes across billions of spatially separated neurons bears little resemblance to computing. Although functionalism is probably still the dominant orthodoxy, there is now more of a ground swell of awareness of the differences between computers and brains, and the authors do feel it necessary to address these reservations. They seem to put forward the argument that the operation of the gamma synchrony could be digitally replicated, although this isn't really clear. No doubt a computer could in principle replicate such connections, but this leaves open the question as to whether the basis for consciousness in the brain relates to the connections as such, or the physical/biological structures that allow them. This could be a subject of some discussion, but no discussion appears to be considered necessary in this chapter.

A further problem here appears to be that the working of human-made computers is fully understood, and provides no examples of structures that do not exist elsewhere in the universe without them producing consciousness. On the other hand, our understanding of the brain and more especially the neuron's complexity at the microscopic level is less certain. It is noticeable that while philosophy and psychology talk in terms of certainties with relation to the mind, the nitty gritty of neuroscientific literature is hedged by 'perhaps' and 'could be'. Furthermore, the gamma synchrony, as is admitted even in the most conventional circles, is only a correlate of consciousness. Is it consciousness that produces the synchrony, visa versa or some interactive process between neurons and the brain-wide synchrony?

Mind-brain identity:  The writers are also supporters of mind-brain identity. The core of the mind-brain identity concept is that mental states and neural states are identical. In a trivial sense this appears to be true of all theories of consciousness that are not dualistic, so that even a Penrose-Hameroff theory of consciousness could be argued to be a mind-brain identity theory. Thus Penrose argued that the mind was not identical to a computer rather than not identical to a brain.

However, in modern consciousness studies mind-brain theories tend to travel with a certain hidden agenda. The mind is identical to the brain as described by neuroscience text books. So far so good, except that when we read such a text book, there is nothing in it which either requires or could generate consciousness. We are presented with a closed information system from which consciousness is entirely missing. Incidentally an end chapter, which may be found in some more recent books, giving a round up of current theories of consciousness does not constitute an explanation of why consciousness is missing from the main text. The problem we have in conventional mind-brain identity theory is that the mind is claimed to be identical to a brain that, as described, has no requirement for consciousness and had no way of generating it.

Elsewhere this chapter has a rather confused take on some other theories of consciousness. Curiously, the authors appear to conflate quantum consciousness with epiphenomenalism. The assumption appears to be that any quantum states in the brain must be by-products of processes based on classical physics, suggesting a rather strange take on physics, and this is odder still because epiphenomenonalists tend to indignantly reject the idea of any quantum involvement. Another curious idea is the conception of persistence through time as the factor underlying consciousness. Admittedly awareness or record of lifespan to date is usually part of the contents of human consciousness, but it is another thing to say that this produces consciousness. A non-conscious computer only needs a clock to record how long it has been in existence. It is also noticeable in this piece that in a fashion reminiscent of twentieth century thinking cognition is frequently equated to consciousness or the potential for consciousness, while emotion or evaluation of sensory input is hardly mentioned. Recent neuroscience, however points to a significant involvement of these latter factors.




7.)

The quest for animal consciousness

Andrea Nani, Clare Eddy & Andrea Cavanna, Universities of Turin, Birmingham and UCL

Journal of Cosmology, 2011, Vol. 14

Keywords:  conscious sensory information, consciousness and executive function

INTRODUCTION:  The most interesting aspect of this paper is the reference to studies demonstrating that only sensory information that is reported as conscious in humans is able to activate brain regions dealing with executive functions.


Studies of neural activity indicate an overlap between human and animal activity. Studies in many species suggest that some behaviours cannot be explained simply by stimulus and response. In humans there is a marked difference between the EEGs of conscious and unconscious subjects. Conscious activity is particularly associated with the approx. 20-70 Hz gamma synchrony. The distinctive EEGs as between waking states, and states regarded as unconscious in humans is also apparent in all mammals that have been studied in this respect. Conscious activity in humans correlates with specific interactions between the thalamus and the cortex, which are also found in animals. The thalamocortical system appeared mainly in mammals about 100 million years ago. Birds possess functionally comparable structures. The tendency for consciousness to be related to widespread activity in the brain is also found in animals performing functions that are correlated to consciousness in humans.

Studies (Frackowiak, 2004) shows that in humans only sensory information that is reported as conscious activates the executive regions of the brain. The dorsolateral prefrontal is normally seen as the most important region of the brain in this respect. This implies that consciousness has an essential functional role in the human brain, and something similar is likely to arise in other mammals given their similar brains. Studies of animal behaviour produces instances of where they have to form simple executive plans, or have anticipated the likely future location of objects.




8.)

Conscious states are a crosstalk mechanism for only a subset of brain processes

Ezequiel Morsella & Tiffany Jantz

In:- Consciousness and the Universe

Keywords: Consciousness, orbitofrontal, intra-brain communication

The authors accept the consensus view that conscious states represent only a subset of brain processing, and that the integration of sensory information and most cognitive processes are unconscious, . It is suggested that identification of processes that are unconscious can reveal those processes that involve consciousness by a process of elimination. The hypothesis here is that consciousness establishes intra-brain communication for a subset of brain processes. These brain processes are suggested to the control of voluntary actions. This is designated as supramodular interaction theory (SIT).

The authors specify what is not involved in SIT. It does not relate to complexity, feedback, memory or meaning. Instead their attention is focused on conscious conflicts such as holding breath, pain suppression, suppression of socially inappropriate behaviour, or a physically difficult process such as trying to look right when there is a bright flash to the left. It is suggested that consciousness is involved when two brain processes work towards different actions. Where there is just a single stream of processing leading to an action, such as withdrawing a hand from a hot stove, there is no requirement for consciousness. In situations of conflict, it is suggested that the impulses from different and conflicting streams of brain processing are held in the 'conscious field'. The authors describe the muscular system used for actions as a steering wheel that different parts of the brain try to control. Consciousness is viewed as the process by which conflicting parts of the brain communicate with one another. The authors accept that some process other than consciousness could in principle resolve these conflicts, but say that evolution has selected for consciousness to perform this function.

The authors think that within the brain consciousness derives from a particular type of processing involving interaction between regions rather than depending on a particular region. Different outcomes result according to whether there is interregional activity or not. Unconscious processing involves smaller brain networks than conscious processing. Consciousness is related to the ventral stream which is not used for execution of action, but is involved in knowledge-based selection of actions. P. The authors are cautious in respect of the hypothesis that consciousness derives from the feedback loop between cortical and thalamic neurons, because we consciously experience smell, although in contrast to the other senses olfactory neurons go directly to the cortex, mainly the orbitofrontal and pyriform cortices rather than via the thalamus. However, the thalamus does subsequently receive inputs from the regions involved in olfactory processing.

Recent studies are claimed to show that consciousness is only involved in perceptions preceding actions or the experience of the result of actions. This chapter also touches on suggestion going back to Penfield in the mid twentieth century that consciousness derives from the subcortical rather than the cortical regions of the brain. The authors criticise the rush to label consciousness as an epiphenomena without understanding much about it.

This chapter seems to try to steer the consciousness debate towards the area of choice/preference or as described here the resolution of conflict, which accords with other studies correlating activity in evaluation/choice areas of the brain with subjective preferences or assessments. The suggestion that consciousness only arises in the communication of larger brain networks also accords with recent studies of the gamma synchrony. However, as the authors themselves remark there is no attempt to describe how subjectivity arises in a physical system, only how it functions.