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Summaries and reviews of material from mainstream consciousness studies

1.) Comment on 'Lord Immolation' YouTube presentations

2.) Is the brain a quantum computer? - Litt, A, Eliasmith, C. et al - Exemplifies the faults of mainstream comment on quantum consciousness.

This piece is a comment on a series of presentations on YouTube under the name 'LordImmolation'.

http://www.youtube.com/user/LordImmolation

These presentations claim to refute the Penrose/Hameroff theory. With respect to this, I have to say that I find it inexcusable that someone can go public in a high profile way, when they have either not read Penrose, have forgotten what he said, or have simply failed to comprehend it.

A crucial misconception that runs through much of the 'Lord Immolation' (LI) talks is the notion that Penrose is proposing that consciousness is linked to the normal collapse of the wave function, characterised by its random selection of position and other classical states of particles. Penrose himself points out that this random quality of the normal wave function collapse, or decoherence, which happens when the wave/particle becomes sufficiently entangled with the environment, renders it unsuitable as a basis for mathematical understanding.

Penrose, however, goes on to ask what happens to quanta that remain isolated from the environment. This is essentially the Schrodinger cat problem of whether or not there is a limit to the size of quantum superpositions. Penrose speculates that there might be such a limit. Each superposition of a particle is hypothesised to have its own piece of spacetime. Spacetime is here conceived of as a network rather than a continuum. As the wave function evolves, the superpositions grow further apart in spacetime. When this separation reaches the Planck length of 10^-35m, the blister becomes unstable, and the wave function quickly collapses. This type of collapse, not involving contact with the environment, is referred to as 'objective reduction'. Penrose speculates that this form of reduction is neither random nor deterministic, but has the non-computable quality of mathematical understanding. Penrose's position is that this is the only plausible place in the universe that he can find for a property of mathematical understanding that is neither based on a deterministic algorithm nor randomness.

A number of other arguments are advanced by LI. I would agree with LI where he says that the important that the important aspect of emergent properties is the system rather than the sheer number of molecules involved. The emergence of liquidity amongst water molecules is a function of the electrical attraction between their dipoles, and the number of molecules is a secondary factor. However, the main problem for the idea that consciousness as an emergent property is that so far no one has suggested a generally convincing mechanism or system, comparable to the attraction between water dipoles, that would produce consciousness.

With reference to the Godel theorem and Penrose's related concept of mathematical understanding, LI advances the argument that computers can produce estimates, and that this is somehow good enough for mathematical understanding. This looks like the type of fudge that is all too common in consciousness studies. 'The economy will grow by less than 1% in 2010' is an estimate. Such an estimate would be likely to be the product of a computer model, into which certain assumptions have been fed, such as manufacturing output +2%, oil price +6% etc. etc. However, this estimate does not even claim the property of certainty or 'knowing', comparable to the assurance that 'everything I say is untrue' must be a paradox, or that the proposition that 'no odd number is the sum of two numbers' is obviously true, but that a computer programme searching for a contrary example would never stop running.

LI further claims that the Penrose/Hameroff theory is dualist. This would mean that its authors thought that consciousness derived from 'spirit stuff' that was separate from the 'matter stuff' of the physical universe and its laws. In reality, Penrose and Hameroff repeatedly claim that consciousness derives from a fundamental level of the physical universe. It is therefore a monist rather a dualist theory. In this LI seems to confuse 'outside the brain' with 'outside the physical universe'. In any case, I think that the whole question of inside or outside the brain is largely irrelevant in this type of spacetime based theory, since spacetime encompasses the whole universe, both inside and outside the brain.

Is the brain a computer?

Litt, A. Eliasmith et al, Cognitive Science (2006)

INTRODUCTION: This paper exemplifies the faults of mainstream consciousness studies in dealing with quantum consciousness. The authors appear to be mainly intent on showing that classical computing by neurons is sufficient for thought processes, rather than addressing subjective experience, which is the main target of quantum consciousness theories. The authors also fail to discuss debatable claims they make relative to neuroscience, physics and mathematics, notably assertions relative to quantum decoherence, the structure of microtubules and the Godel theorem.

For the main part of the paper, the authors appear to be climbing the wrong mountain. They are intent on showing that classical computing in neurons is sufficient for thought. They do not seem to distinguish between brain processing that is predominantly non-conscious on the one hand and the subjective experience of consciousness on the other. It has been suggested that quantum computing might be necessary for some aspects of brain function, apart from consciousness, but I think that there is an essential difference between this debate and the core idea of quantum consciousness theories. This is that it is necessary to look to a mechanism at the fundamental level, in order to understand subjective experience. We can see that in principle the 10^11 neurons and ten times that number of glial cells and their numerous connections might constitute a mechanism that processes information, solves problems and stores data. But when we come to subjective consciousness, conventional non-quantum theorists find it hard to distinguish a specific mechanism in the macroscopic brain for producing it, and mainly offer assertions that it has to be produced by the total system or some large part of it, possibly as an emergent property. What we lack with these holistic or emergent ideas is a mechanism for how the system produces the new property, comparable to the mechanisms that can be described in classical emergence.

In this respect, the paper's claimed analogy between quantum mechanics, as an explanation of bird flight, and quantum mechanics, as an explanation of the mind could not be more false. The authors argue quite correctly that in bird flight the wings etc. are held together by atomic bonds, but for the purposes of describing how the birds keeps in the air, it is sufficient to use classical physics and to regard the internal atomic bonds as a black box. By contrast, classical physics and conventional neuroscience has failed to come up with a consensus view of how macroscopic brain components, such as neurons, create a classical mechanism of consciousness, and there is therefore no black box reason for excluding quantum influences from the discussion.

Although consciousness is the main subject here, some comment seems needed relative to the discussion of quantum computing and thought processes in this paper seem to be needed. The authors appear to think that quantum consciousness theories relate mainly to activity at the synapses, which is not the case except for aspects of Stapp's theory. As usual, they rely completely on Tegmark (2000), and do not discuss the replies to/criticisms of this paper. In fairness, the Engel (2007) paper on quantum coherence in photosynthetic proteins was published after this paper, but earlier studies were already pointing in this direction. These recent studies put a serious question mark over the Tegmark-based position on decoherence.

In their discussion of the biological aspects of the theory, the authors fall into the frequent error of thinking that given the ubiqitous nature of microtubules in organisms, it is improbable that just the neuron microtubules and none other would produce consciousness. In fact, microtubules in the dendrites of neurons have a quite different structure from other microtubules.

A further curious argument appears in the biological section. The authors discuss spindle neurons that allow a greater degree of self-control and error recognition in humans and apes than in other species, because humans/apes have a greater concentration of these neurons. They seem to view this fact as disproving quantum consciousness. Even by consciousness study standards, this is a stunning non sequitur. No reason is advanced as to why quantum consciousness is incompatible with the existence of spindle neurons. The only reason I can deduce is that the authors are still stuck with an idea that is now outdated even in mainstream circles, to the effect that animals below the level of apes are not conscious. This notion appears to result from a confusion between consciousness and self-consciousness, the latter now usually viewed as part of the contents of the former. The idea may also be a hand-me-down from the old religious idea that animals did not have souls. P. The authors go on to discuss error correction, a process needed for both classical and quantum information processing. They admit the existence of quantum error correction, but argue that it is too complicated to evolve. This rather smacks of 19th century arguments for intelligent design. Their actual argument is based on the rapid decoherence of quantum states in organic matter, which is supposed to make the evolution of quantum error correction difficult. This might be true if the Tegmark argument is sound, but having failed to discuss criticism of this position, they have have failed to really establish their argument.

In discussing objective reduction (OR), the consciousness-related form of wave function reduction proposed by Penrose, the authors adopt a stance that is common, but nonetheless alarming for the future of science. They argue that the objective reduction theory is probably wrong, because it would require revisions to existing physics theory. This theory itself would never have been allowed to emerge if this anti-revisionist approach had been enforced at the beginning of the century. The authors are not mainly physics-orientated, and it may be that they were unaware of the conflict between relativity and quantum theory, as they are now understood, which means that there is in any case a need for revision somewhere in physics. P. The discussion of the Godel theorem and non-computability looks to be a house of cards. We are told that 'numerous respondents' have demonstrated that there is no requirement for non-computability resulting from the Godel theorem. However, the top reference given to support this claim is Grush and Churchland, who merely claim the same thing in their paper, i.e. that many people are opposed to the idea. We never seem to get down to the actual arguments, and the whole thing begins to look like a bit of group think on the part of the AI community, rather than numbers of separate individuals studying the problem carefully, and then coming to a similar conclusion.