Arguments against the physicalist view of consciousness

The following excerpt by Stuart R. Hameroff is a rather "thick" read however it raises some interesting questions regarding the origins of experiencial consciousness and (if you follow the link below) tries to answer the question of whether consciousness is in fact a fundamental aspect of the universe.

Quote :

Brain = Mind = Computer?

The basic physicalist idea is that the mind is a computer functioning in the brain's neural networks. The current leading candidate for a computer-like "neural correlate" of consciousness involves synchronously oscillating feedback loops of thalamo-cortical neurons. Higher frequencies (collectively known as "coherent 40 Hz") have been suggested to mediate temporal binding of conscious experience (e.g. Singer, Gray, Crick and Koch, etc.). The proposals vary, for example as to whether coherence originates in thalamus or resonates in cortical networks, but "thalamo-cortical 40 Hz" stands as a prevalent view of the substrate for consciousness.

But how do synchronized neural firings and synaptic transmissions produce experiential qualia, emotions or free will? Physicalists believe this to be relatively straightforward (brain = mind = computer) however others find the question intractable, or as vexing as trying to coax a reluctant genie from a magic lamp. I see three problems with the brain = mind = computer analogy:

1) Is consciousness classical computation? In a controversial stance Roger Penrose 1-3 has asserted that essential aspects of consciousness are non-computable. But regardless, classical computers appear to be evolving toward quantum computers. Beginning in the early 1980's Benioff, Feynman and others proposed that states in a system - bits in a computer - could interact while in quantum superposition of all possible states, effecting near-infinite parallel computation. Rather than classical Boolean bit states 1 or 0, quantum computers would utilize interactive "qubits" of 1 and 0. If quantum computers can ever be constructed they will have huge advantages in important applications. As the brain/mind has always been cast as current information technology, consciousness may inevitably be seen as some form of quantum computation.

2) Are neural firings the "fine grain" of consciousness? Cells and synapses are far more complex than simple on­off switches. Consider the paramecium, a single cell organism which gracefully swims, avoids predators, learns to escape from capillary tubes, and finds food and mates. Observing intelligent behavior in unicellular creatures C.S. Sherrington said in 1951: "Of nerve there is no trace. But the cell framework, the cyto-skeleton, might serve." Lacking synapses, paramecium utilizes its cytoskeleton for communication and organization. Neurons have a rich and dynamic set of cytoskeletal microtubules which regulates synapses, and tremendously increases potential computational capacity (e.g. 1016 bit states/second/neuron)4. More importantly, neurons are alive and we don't yet know what that implies for consciousness.

3) Details which don't fit the brain = mind = computer scheme are overlooked.

For example:

a) Neurotransmitter vesicle release and cognitive reaction times are "noisy", and exhibit apparent probabilistic randomness (?non­computable quantum indeterminacy5).

b) Axonal firing patterns (rather than average frequency) and dendritic­dendritic processing may be relevant to consciousness6.

c) Apart from chemical synapses, primitive electrotonic gap junctions couple neurons and glia synchronously and may play an important role in consciousness.

d) Glial cells (80% of the brain) are ignored in the brain­as­computer view.

Quibbling aside, the physicalist view fails to address difficult issues. For example the problem of 'binding' in vision and self is often attributed to temporal correlation (e.g. coherent 40 Hz), but it is unclear why temporal correlation per se should bind experience without an explanation of experience.

Regarding transition from pre­conscious or implicit processing to consciousness itself, the physicalist view sees emergence at a critical level of neural-level computational complexity. But no conscious threshold is apparent, nor is there a reasonable suggestion why such an emergent property should have conscious experience. As physicalism is based on deterministic computation, it is also unable to account for free will or Penrose's proposed non­computability. But the major problem remains experience, for which physicalism offers no testable predictions. Something is missing.

The final paragraph is the most compelling argument for me and is the reason I take a pan-experiencial position on consciousness.

The essay continues here...
http://cogprints.org/369/00/tics.html

I'm somewhat familiar with the Penrose/Hameroff model and accept it as most likely correct. But I do have some reservations about his contention that consciousness can not arise at the neural level.

The ion channels on the axon are also in the same size range as microtubules and thus just as susceptable to quantum influences.

It seems to me a model that views the mind as a closed loop arising out of the brain as an epiphenomenon could intersect these neurons at the ion channels which regulate the flow of those molecules which cause them to fire. If those channels are balanced just right a slight increase in probability will push them past the threshold level at which the cell will fire.

Applying Fourier's system of composite waveform mathematics a completely closed loop (configured something like a Klien bottle) would accumulate through experiance a unique "vibrational signature". By simply flexing or stretching itself such a structure could scroll through potential responses select and intersect the appropriate neural circuits at the ion channels and initiate a behavorial response to a given stimuli.

Such a model (based in an idealistic framework) would eliminate Descarte's dualism problem since the brain and mind are both fundamentally the same while explaining free will.

By reversing the process it may also be possible to explain cognition.

So the mind could be looked at as a self-referential (sometimes refered to as a 'strange loop') concept arising from the brain as an epiphenomenon which is able to percieve and act in the world through interaction with the brain through the ion channels at the quantum level.

I don't know what you just said but it sounded good.

it doesn't matter

(that's two matter zingers...i'm a nerd! )

Yes you are quite the nerd.

that's me!