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As of today, the conscious brain remains as elusive and as baffling as ever. In a bid to get at least a plausible inkling as to exactly what it takes - and above all, why - for a physical process to yield consciousness, I put forward the cognitive iceberg model of perceptual awareness. This iceberg is made of an "underwater part", where incoming sensory stimuli are encoded in the shape of what I call the suprels . Visual suprel s, for instance, are typically made in the visual cortical areas, where they remain unconscious. (This is to account for preconscious brain processing.) Then they are sent into the "tip", where specific microstructures (dubbed the paralgens ) turn them into qualia . (This deals with conscious brain processing.) The foregoing model may shed new, if tentative, light on such conundrums as: the binding problem; the nature of declarative memory; and the 'upshot problem', whereby what we become aware of is the result, or upshot, of neural computations, rather than of the computations themselves.
In this paper I set out to outline a tentative approach to the hard problem of consciousness (Chalmers, 1995). It rests on the hypothesis of psychomatter , according to which matter (call it 'phi' - for physical) may well enshroud an unseen content (call it 'psi' - for psychic), that would be qualitatively different from it. This view is akin to that of panpsychism or panprotopsychism, as proposed by Seager and Rosenberg (see Chalmers, 1997).
To get this idea off the ground, I need to posit a further three broad items. They are:
1. As a rule, the 'psi' component of psychomatter does not show, because it is overwhelmingly latent - whereby it remains stark unconscious. It requires specific conditions to be stirred out of its latency - thereby becoming conscious. I call paralling conditions these "psi-stirring" conditions.
2. When the 'psi' is stirred out of its latency, it forthwith becomes conscious and active. It thus interferes with the 'phi' part of psychomatter. (In this "off-latent" state, 'full-blooded' consciousness is mostly a matter of scale or threshold.) I call paral interaction or paral phase (or else, paralling ) this 'psi'-'phi' interaction. It may hold the key to the mind-body interaction.
3. The conscious self has a knack to experience itself as a unified, coherent whole. However, there seem to be no conclusive underlying neural mechanism that would thoroughly account for this. I therefore assume that the 'psi' parts of, say, various specks - or 'elementary particles' - of psychomatter can be seamlessly bundled together into an overall 'psi' entity. I christen supralness this ability. I call supral link or supral interaction any existing bond of supralness .
In a nutshell, the big difference between 'psi' and 'phi' (Ransford, 1996) is that the former is endo-causal whereas the latter is exo-causal. (Endo-causation comes down as an element of indeterminacy while exo-causation is deterministic.) As for the paralling conditions (Ransford, 1997), they are linked to the energy makeup of ( psycho- )physical systems.
The M-P-S diagram summarizes the above at a glance. (See figure.)
Here q 1 = ( y 1 , j 1 ) and q 2 = ( y 2 , j 2 ) stand for two elementary particles of psychomatter.
One has: - M : material interaction (between j 1 and j 2 )
- P : paral phase or paralling (between y i , j i ) [ j is 'phi'; y is 'psi']
- S : supral link or interaction (between y 1 and y 2 )
How can we tell M, P and S apart? Given what these interactions are, telling them apart amounts to find out - or, for that matter, to surmise - what diffentiates 'psi' and 'phi'. With an eye on contemporary physics, I propose the following: 1. 'phi' is thoroughly deterministic, i.e. is exo-determined. It complies with the mathematical principle of least action. (Relativity provides another example of "phi-determinism".) 2. 'psi' is just the opposite: it embodies an element of endo-determinacy (which bestows a seeming randomness on it); and it breaks free from the " phi-determinisms".
To sum up: the 'phi' part ('phi') behaves according to both the principles of least action and relativity; whereas the 'psi' part ('psi') exhibits an element of nondeterminism, and runs regardless of these determinisms. (However, it does so only when it becomes active, or "off-latent", namely whenever a paralling is triggered. When latent, it displays nothing!) Therefore: A paralling is genuinely nondeterministic; it breaches the least action principle and the relativistic constraint.
All this consistently pins the paral phase down as what quantum physics knows as the wavefunction collapse. (Yet the paralling conditions are of a wider - and slightly distinct - class than the measurement processes.)
As for supralness, we recall that a supral link amounts to weld, or blend, hitherto unrelated 'psi' parts into a unified, coherent whole. Hence, it correlates these parts. Besides, unless the 'psi' becomes active, these telltale correlations remain stark hidden. Furthermore, supralness being 'psi'-related through and through, no "phi - determinism" holds its sway on it. Therefore : Supralness, for one , is (light-cone-blind or) relativity-blind. For two , it correlates various 'psi' parts within psychomatter - this (for three!) being on display only when a paral phase comes off.
All of the above unambiguously pins supralness down as what is known as quantum entanglement, a.k.a. nonseparability.
To carry on with my attempted theory - which bears some resemblance to that of Hameroff and Penrose (1996) -, two ideas come forth as paramount. They are: 1. The brain is conscious because it brings about "psi-stirring" paralling conditions on wide enough a scale. These conditions would actually be achieved by the brain paralgens , alleged microstructures yet to be found. 2. The threads of supralness weave unseen 'psi'-webs within psychomatter; they thus bring structure into the 'psi' level. Owing to this, the 'psi' content is information-laden.
The view, in short, is that awareness stems from supralled paral or paralled supral ; on the insight that there is a mapping of sorts between the objective structural features on the one hand, and the subjective informational contents on the other, of supralness. ( Paral is the state psychomatter is in during a paralling.)
To illustrate the above, let us take an example: vision. Very roughly, the bulk of the brain visual processing is distributed over many different areas in the brain. Yet, there seems to be no conclusive mechanism for combining all the operations of this separate but parallel processing into the coherent representation of what is felt as a mental image. This lack of acknowledged mechanism is known as the binding problem . The matter, to make things worse, is further compounded by what I call the upshot problem; which refer to the tantalizing fact that visual awareness knows of the outcomes, or upshots, of neural computations "rather than [of] the computations themselves" (Johnson-Laird, 1983).
The cognitive iceberg (Ransford, 1995) may help to sort these problems out. This iceberg is a (very sketchy) two-stage model of how sensory (e.g. visual) awareness could be achieved in the brain; to wit:
Conversely and by the same token, the qualia vanish no sooner the suprels squirt out of the paralgens. (Their 'psi' becomes latent - and accordingly unconscious - all over again.) This is straightforward enough. However, inasmuch as the suprels have not been shattered along the way, they end up stashed-in-waiting somewhere in the brain (in a distributed or nonlocal way, as supral entities). So their information contents live on, unheeded. In short, these 'fallen' qualia are (unconsciously) memorized . They are recalled whenever, for some reason, they are sent back on to the paralgens. (The weight of the empirical evidence points to an involvement of the hippocampus at least in the recall.) We readily draw from this that our mental (i.e. explicit, or declarative) memory is supral in essence.
We may also get some fresh insight regarding two other puzzles:
Needless to say, all of the above is for now fairly untrammeled speculation. But at least it gives an idea of how we can try and put the psychomatter hypothesis to work. (Let us bear in mind that the cognitive iceberg is meant to address sensory awareness only. Alternative models will cater for other cognitive skills, e.g. such as willed, or volitional, motor functions.)
Given the size of this paper, I shall limit myself to bring into focus - very swiftly, at that - the issue of the paralgens. What and where could they be in the brain? Paralgens are meant to allow for an ongoing and heightened production of supralled paral in the brain. As such, they should bear the hallmark of a high local non-linearity, and cast a distinctly noncomputational shadow in the overall brain processing. (These features hark back to the notion of endo-causation.) This is the kind of clues that we need to track them down. (More of them are at hand.)
The paralgens are set to 'enparal' the flows of incoming suprels: to be up to the job, they must stand in the way of these flows. (Brain-made suprels, by the way, can be thought of as 'hooked' on clusters of biochemical ions, molecules, and the like). This prompts me to target some post-synaptic ionic channels and gates, as likely "paralgenic" microsites. My (educated) guess goes to the NMDA receptor channels: they seem to have the right features to play host to some paralgens.
Indeed, my claim (Ransford, 1995) is that some of the brain paralgens - if they exist at all - are likely to be tucked inside the postsynaptic NMDA receptors found on the dendritic synapses of large glutamatergic pyramidal cells in the fifth layer of the neocortex. (A consistent and significant body of data points in that direction. It goes from considerations surrounding attention and working memory - as spelled out by Crick (1994) - to more particular findings. Flohr (1996), for example, stresses that "General anaesthetics have a common operative mechanism: they directly or indirectly affect the function of the NMDA system.")
In light of the foregoing, I believe that we have at least a lead - however thin - to start from and elaborate on. On that basis we might perhaps, one day, put the M-P-S model of psychomatter to the test. What is at stake, though - albeit more remotely - is no less than exo-biological awareness . (In line with the present approach, it would critically rest on our ability to work and carry out artificial paralgens; and then to tie them skilfully, in order to churn out the relevant suprels.)
Chalmers, D.J. (1995), 'Facing up to the Problem of Consciousness', Journal of Consciousness Studies , 2 (3), pp. 200-19.
Chalmers, D.J. (1997), 'Moving forward on the Problem of Consciousness', Journal of Consciousness Studies , 4 (1), pp. 3-46.
Crick, F. (1994), The Astonishing Hypothesis (London: Simon & Schuster)
Flohr, H. (1996), 'An Information Processing Theory of Anaesthesia', Consciousness Research Abstracts, "Tuscon II" , p. 70.
Hameroff, S.R. and Penrose, R. (1996), 'Conscious Events as Orchestrated Space-Time Selections', Journal of Consciousness Studies , 3 (1), pp. 36-53.
Johnson-Laird, P.N. (1983), Mental Models (Cambridge, MA: Harvard Univ. Press)
Ransford, E. (1995), 'Peeking at the Conscious Brain: New Clues, New Challenges', Journal of the Western Chapter of the Alternative Natural Philosophy Association (ANPA) , 5 (2), pp. 6-26.
Ransford, E. (1996), 'Elementary Particle or 'Wavicle'? Seeing through the Quantum Fog', Philosophy, Proceedings of ANPA 17 , pp. 217-42.
Ransford, E. (1997), 'From Naught to Aught: a Conceptual Inquiry', Mereologies, Proc. of ANPA 18 , pp. 112-33.
Rosenberg, G.H. (1996), 'Rethinking Nature: a Hard Problem within the Hard Problem', Journal of Consciousness Studies , 3 (1), pp. 76-88.