Physics textbooks tell us that everything in the universe is either matter or energy. But what about human mind and all the subjective experience it gives us? In which category they fall? When I see a red flower; I don’t see any wavelength or a frequency; I see “red”. Where is the place for the “red” in the physical world? To physicist red or any other light is just number of oscillation of electric and magnetic field per unit time- which is a number, physical scientists kept no place for color in their theory and view of the world. Similarly when I feel pain- a neuroscientist will say “These exact events have taken place inside your brain”. But these events are just events (physical and chemical in nature), how they can be anything close to pain!
Consciousness one of the important property of human brain, most important one for us (for our inner life) – is still intangible to science. For this very property we know that we and everything else exist. Without which the universe would still exist without anyone knowing that it exist – like a drama with no audience. Peoples have thought about the problem of consciousness for ages. Some people think that problem of consciousness is beyond the scope of science. Some other think consciousness is not a real thing, it is an illusion. But I think it can’t be an illusion, because for every illusion there must be a victim (which is real). If consciousness is an illusion then whom the illusion is for? When there is none to be eluded the conjuration of illusion is pointless.
Generally consciousness is explained as an emergent property of classical (not quantum; difference will be clear at the later part of the writing) computer-like activity in brain’s neural network. According to this view; pattern of neural network correlate with mental state. Which means there is a mapping between particular pattern of neural network and mental state. Consciousness arises from computational complexity among neurons. This view suggests that classical computer will become conscious when certain level of complexity is reached.
I personally don’t favor this view; because it says that consciousness arise simply because a lot of computation is going on. The notion of consciousness as an emergent property misses the main point. It fails to explain the nature of subjective experience, which is to me the main reason it (consciousness) need to be explained at all. The whole idea of consciousness arise from classical computational complexity is somewhat close-minded; it seems to ignore the difficulty and say that consciousness just happens. We all know consciousness happens, but this theory can’t specify any threshold for it’s emergence.
I think the raw component of mental processes is a fundamental property of the universe. Like mass, charge, spin etc it is a fundamental property that exists. This view is not new, it has long been held by Eastern philosophers claiming a “universal mind”. Bertrand Russel claimed that there is a common entity underlying both mental and physical process; which is neither mind nor body but out of which both can spring.
Now I’ll try to briefly describe one model consistent with this view. It is called “Orchestrated Objective reduction” model given by Roger Penrose and Stuart Hameroff. In this model conscious event take place in a wide, basic field of proto-conscious experience. It is associated with fundamental space-time geometry. I’ll not go into detail of the quality of the field of proto-conscious experience, because it requires considerable grasp in theory of relativity and quantum mechanics. It’s sufficient to say for the present purpose that particular space-time geometry would convey particular type of qualia (subjective quality of conscious experience). So this qualia is inherent in the very fabric of nature.
Another principle proposition made by Roger Penrose is; quantum superposition spontaneously collapse (because of objective interruption from intrinsic quantum gravity) to specific state at a critical threshold of space-time separation. This objective threshold is defined by the indeterminacy principle:
E=h/T
E = gravitational self energy
H = plank constant/2 pi
T = time
This spontaneous collapse is termed “objective reduction”.
Collapse of quantum superposition can be induced by outside intervention. Quantum superposition can carry a lot of information and the result can be obtained by inducing the collapse of the super-position. This is the basis of quantum computation.
Proponent of Orchestrated Objective Reduction model suggested that brain contains structure which can do quantum computation. Their favorite candidate was microtubule automata. These structures can interact with each other through quantum entanglement, when physically separated. According to the model:
1) Quantum superimposition/computational phase correspond to pre-conscious state and Objective reduction or collapse of superposition correspond to awareness.
2) Tubulin sub-units in different part of the brain can interact with each other through quantum entanglement and enables the binding of information from different part of the brain and form a unitary experience. When we are conscious we are simultaneously aware of a lot of facts like sound, smell, vision, touch, breathing, inner thought etc. These activities take place all over the brain but they come together to form a single coherent subjective experience, quantum entanglement explain this integration.
3) To count as really conscious a threshold frequency of awareness stimulating event are necessary. Sequence of objective reduction events gives rise to conscious feeling. It also forms the basis of subjective time flow. If the frequency of objective reduction is below the threshold it can’t counted as truly conscious.
4) Each event of objective reduction determines specific classical state which subsequently regulates synaptive and neural function.
5) During the pre-conscious quantum superposition/computational phase oscillation are tuned and orchestrated by microtubule associated proteins (MAPs) providing feedback loop between biological system and quantum state. In other words MAPs work as a bridge between quantum state and biological system.
6) The outcome of the objective reduction is neither deterministic nor probabilistic but non-computable, because it is chosen by the effect of the hidden logic on the quantum system poised at the edge of objective reduction. This non-computability opens the door for free will.
Figure: Orchestrated objective reduction model
This particular model may be right or wrong but I think this type of model is required for settling the issue of consciousness.
Before finishing the writing I’ll talk about kind of a subjective dilemma that once haunted me.
It is about this “I” which is tied up with a particular body and apparently is always associated with that particular body. We know living body is not a constant structure with respect to the molecules that have composed it rather it is a dynamic structure which maintain certain shape, size, composition of matter etc. Body is subject of change and re-organization. All the molecules associated with the body can be completely replaced in time, but this “I” suggest that “I am the same “I”.” Now the body is not the same body (as far as the molecules are concerned) but this “I” seems to be the same.
If some molecular events give rise to this “I” like feeling (it’s not a feeling, I think everyone knows so please endure the mistake) at this moment, these events must happen again to give the feeling the next moment. Now there are many brains inside which these events are going on. Since this “I” is not exactly connected with some set of molecules why my “I” is never exchanged with his “I”? Actually we will never understand the difference. Because if his “I” and my “I” is exchanged, his “I” will have only access to my brain and information stored in it and he’ll believe that he was with my body from the beginning as firmly as “I” believe that “I” was with my body from the beginning. This suggests his “I” and my “I” is the same – in the sense that two electrons are same. When one electron is exchanged for other it does not make any difference - not only that it is even impossible to demonstrate by any experiment that the electron was exchanged at all. I guess same thing applies for this mysterious “I”, i.e. all “I”s are exchangeable without making any difference.
The false impression (I think) that a discrete and unique “I” is associated with every “body” is an illusion created by brain. Consciousness or “I” is not an illusion but the idea that discrete and unique “I” is associated with every “body” is an illusion. I think there is no particular “I” locked up with particular body as there is no particular molecule locked up with a body. If I create a completely radio-labeled bacterium and let it grow (not divide) in nutrient medium free from any radio-labeled substances – it will eventually lose all of the radio-label except that of the DNA. It’s still the same bacteria with completely different set of molecules. In similar way we can (though we should not) let a newborn baby take radio-labeled C,H,O,N,P containing nutrient for 20years and get a completely radio-labeled man with not a single atom from the baby but we all agree that it is the same baby grown-up. It is because both the baby and the man has a common history in their life, their life history merges and become one at some point which give them the same identity. Cellular and molecular structures are destroyed and regenerated as a constant process, consciousness also have the same quality. Consciousness which make us feel “I am the person” is created from continuous events inside the brain. When a new “I” is created it is necessary that it feels that it is the same “I” created some fraction of second ago.
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