CHAPTER NO:- 11 》MECHANISM OF REINCARNATION PART:-2 》Mystery of Consciousness - Body-mind problem, Hard Problem of Consciousness.

▪ In the previous part that is Chapter no 11 part 1 you have read about in detail about Consciousness, Types of Mind like  Conscious, Subconscious, Unconscious Mind,

▪ Now in this chapter you are going to read aboutNeural correlates of consciousness as an approach to the Mechanism of Consciousness and its problems Body-mind problem, Hard Problem of Consciousness.


1. What is the mechanism of Consciousness


NCC - Neural Correlates of Consciousness is the Currently Scientifically Accepted theory of Mechanism of Consciousness.

The neural correlates of consciousness (NCC) constitute the minimal set of neuronal events and mechanisms sufficient for a specific conscious percept. Neuroscientists use empirical approaches to discover neural correlates of subjective phenomena. The set should be minimal because, under the assumption that the brain is sufficient to give rise to any given conscious experience, the question is which of its components is necessary to produce it.

Medical Science Evidence to this NCC Approach is

The view in Neuroscience is that consciousness as we know it is entirely generated by the brain and does not exist separately from or independent of the brain.

▪ The Evidences for believing this are straightforward: Chemically and electrically interacting with the brain can modify or extinguish consciousness (dreamless sleep, general anesthesia, drugs, brain death); and there have been no reproducible experiments that have been able to show causal interaction with consciousness without interfacing with the brain first.


Problems with Neural Correlates of Consciousness Approach to the Mechanism of Consciousness

▪ A science of consciousness must explain the exact relationship between subjective mental states and brain states, the nature of the relationship between the conscious mind and the electro-chemical interactions in the body (mind–body problem).

▪ Progress in neuropsychology and neurophilosophy has come from focusing on the body rather than the mind. In this context the neuronal correlates of consciousness may be viewed as its causes, not as mechanism and consciousness may be thought of as a state-dependent property of some undefined complex, adaptive, and highly interconnected biological system.

▪ Discovering and characterizing neural correlates does not offer a theory of consciousness that can explain how particular systems experience anything at all, or how and why they are associated with consciousness, the so-called hard problem of consciousness, but understanding the NCC may be a step toward such a theory.

▪ Most neurobiologists assume that the variables giving rise to consciousness are to be found at the neuronal level, governed by classical physics, though a few scholars have proposed theories of quantum consciousness based on quantum mechanics.

▪ There is great apparent redundancy and parallelism in neural networks so, while activity in one group of neurons may correlate with a percept in one case, a different population might mediate a related percept if the former population is lost or inactivated. It may be that every phenomenal, subjective state has a neural correlate.

▪  Where the NCC can be induced artificially the subject will experience the associated percept, while perturbing or inactivating the region of correlation for a specific percept will affect the percept or cause it to disappear, giving a cause-effect relationship from the neural region to the nature of the percept.

What characterizes the NCC? What are the commonalities between the NCC for seeing and for hearing? Will the NCC involve all the pyramidal neurons in the cortex at any given point in time? Or only a subset of long-range projection cells in the frontal lobes that project to the sensory cortices in the back? Neurons that fire in a rhythmic manner? Neurons that fire in a synchronous manner? These are some of the problems that have been advanced over the years.

▪ The growing ability of neuroscientists to manipulate neurons using methods from molecular biology in combination with optical tools (e.g., Adamantidis et al. 2007) depends on the simultaneous development of appropriate behavioral assays and model organisms amenable to large-scale genomic analysis and manipulation.

▪ It is the combination of such fine-grained neuronal analysis in animals with ever more sensitive psychophysical and brain imaging techniques in humans, complemented by the development of a robust theoretical predictive framework, that will hopefully lead to a rational understanding of consciousness, one of the central mysteries of life.

BODY-MIND PROBLEM AND HARD PROBLEM OF CONSCIOUSNESS ARE CONSIDERED TO BE THE PROBLEM WITH NEURAL CORRELATES OF CONSCIOUSNESS AND ALSO AS MYSTERY OF CONSCIOUSNESS.


2. BODY- MIND PROBLEM


The mind–body problem is the problem of explaining how mental states, events and processes—like beliefs, actions and thinking—are related to the physical states, events and processes, given that the human body is a physical entity and the mind is non-physical.

▪ The problem was addressed by René Descartes in the 17th century, resulting in Cartesian dualism, and by pre-Aristotelian philosophers, in Avicennian philosophy, and in earlier Asian traditions.


▪ A variety of approaches have been proposed. Most are either dualist or monist.

Dualism maintains a rigid distinction between the realms of mind and matter. Monism maintains that there is only one unifying reality, substance or essence in terms of which everything can be explained.

▪ Each of these categories contain numerous variants.

▪ The two main forms of dualism are Substance dualism, which holds that the mind is formed of a distinct type of substance not governed by the laws of physics, and property dualism, which holds that mental properties involving conscious experience are fundamental properties, alongside the fundamental properties identified by a completed physics.

The three main forms of monism are physicalism, which holds that the mind consists of matter organized in a particular way; idealism, which holds that only thought truly exists and matter is merely an illusion; and neutral monism, which holds that both mind and matter are aspects of a distinct essence that is itself identical to neither of them.

▪ Several philosophical perspectives have been developed which reject the mind–body dichotomy. The historical materialism of Karl Marx and subsequent writers, itself a form of physicalism, held that consciousness was engendered by the material contingencies of one's environment. An explicit rejection of the dichotomy is found in French structuralism, and is a position that generally characterized post-war French philosophy.

▪ The absence of an empirically identifiable meeting point between the non-physical mind and its physical extension has proven problematic to dualism and many modern philosophers of mind maintain that the mind is not something separate from the body.

▪  These approaches have been particularly influential in the sciences, particularly in the fields of sociobiology, computer science, evolutionary psychology, and the neurosciences.

▪ An ancient model of the mind known as the Five-Aggregate Model explains the mind as continuously changing sense impressions and mental phenomena.

▪ Considering this model, it is possible to understand that it is the constantly changing sense impressions and mental phenomena (i.e., the mind) that experiences/analyzes all external phenomena in the world as well as all internal phenomena including the body anatomy, the nervous system as well as the organ brain.

▪  This conceptualization leads to two levels of analyses:

(i) analyses conducted from a third-person perspective on how the brain works, and

(ii) analyzing the moment-to-moment manifestation of an individual’s mind-stream (analyses conducted from a first-person perspective).

▪ Considering the latter, the manifestation of the mind-stream is described as happening in every person all the time, even in a scientist who analyses various phenomena in the world, including analyzing and hypothesizing about the organ brain.


Mind–body interaction and mental causation

▪ Philosophers David L. Robb and John H. Heil introduce mental causation in terms of the mind–body problem of interaction:

“Mind–body interaction has a central place in our pre theoretic conception of agency... Indeed, mental causation often figures explicitly in formulations of the mind–body problem.... Some philosophers... insist that the very notion of psychological explanation turns on the intelligibility of mental causation. If your mind and its states, such as your beliefs and desires, were causally isolated from your bodily behavior, then what goes on in your mind could not explain what you do... If psychological explanation goes, so do the closely related notions of agency and moral responsibility...Clearly, a good deal rides on a satisfactory solution to the problem of mental causation [and] there is more than one way in which puzzles about the mind's "causal relevance" to behavior (and to the physical world more generally) can arise”.

▪ “[René Descartes] set the agenda for subsequent discussions of the mind–body relation.

According to Descartes, minds and bodies are distinct kinds of substance. Bodies, he held, are spatially extended substances, incapable of feeling or thought; minds, in contrast, are unextended, thinking, feeling substances.

▪ If minds and bodies are radically different kinds of substance, however, it is not easy to see how they could causally interact... Princess Elizabeth of Bohemia puts it forcefully to him in a 1643 letter.

how the human soul can determine the movement of the animal spirits in the body so as to perform voluntary acts—being as it is merely a conscious substance. For the determination of movement seems always to come about from the moving body's being propelled—to depend on the kind of impulse it gets from what sets it in motion, or again, on the nature and shape of this latter thing's surface. Now the first two conditions involve contact, and the third involves that the impelling thing has extension; but you utterly exclude extension from your notion of soul, and contact seems to me incompatible with a thing's being immaterial”.

▪ Elizabeth is expressing the prevailing mechanistic view as to how causation of bodies works... Causal relations countenanced by contemporary physics can take several forms, not all of which are of the push–pull variety.

▪ David Robb and John Heil, "Mental Causation" in The Stanford Encyclopedia of Philosophy Contemporary neurophilosopher, Georg Northoff suggests that mental causation is compatible with classical formal and final causality.

▪ Biologist, theoretical neuroscientist and philosopher, Walter J. Freeman, suggests that explaining mind–body interaction in terms of "circular causation" is more relevant than linear causation.

▪ In neuroscience, much has been learned about correlations between brain activity and subjective, conscious experiences. Many suggest that neuroscience will ultimately explain consciousness: "...consciousness is a biological process that will eventually be explained in terms of molecular signaling pathways used by interacting populations of nerve cells..."

▪ However, this view has been criticized because consciousness has yet to be shown to be a process, and the "hard problem" of relating consciousness directly to brain activity remains elusive.

Cognitive science today gets increasingly interested in the embodiment of human perception, thinking, and action. Abstract information processing models are no longer accepted as satisfactory accounts of the human mind. Interest has shifted to interactions between the material human body and its surroundings and to the way in which such interactions shape the mind. Proponents of this approach have expressed the hope that it will ultimately dissolve the Cartesian divide between the immaterial mind and the material existence of human beings (Damasio, 1994; Gallagher, 2005).

▪ A topic that seems particularly promising for providing a bridge across the mind–body cleavage is the study of bodily actions, which are neither reflexive reactions to external stimuli nor indications of mental states, which have only arbitrary relationships to the motor features of the action (e.g., pressing a button for making a choice response).

▪ The shape, timing, and effects of such actions are inseparable from their meaning. One might say that they are loaded with mental content, which cannot be appreciated other than by studying their material features. Imitation, communicative gesturing, and tool use are examples of these kinds of actions.
— Georg Goldenberg, "How the Mind Moves the Body: Lessons From Apraxia" in Oxford Handbook of Human Action


3. Hard Problem of Consciousness


▪ The hard problem of consciousness is the problem of explaining how and why we have qualia or phenomenal experiences, how sensations acquire characteristics, such as colors and tastes.

▪ The philosopher David Chalmers, who introduced the term "hard problem" of consciousness, contrasts this with the "easy problems" of explaining the ability to discriminate, integrate information, report mental states, focus attention, etc.

▪ Easy problems are easy because all that is required for their solution is to specify a mechanism that can perform the function.

▪ That is, their proposed solutions, regardless of how complex or poorly understood they may be, can be entirely consistent with the modern materialistic conception of natural phenomena.

▪ Chalmers claims that the problem of experience is distinct from this set, and he argues that the problem of experience will "persist even when the performance of all the relevant functions is explained".

▪ The existence of a "hard problem" is controversial and has been disputed by philosophers such as Daniel Dennett and cognitive neuroscientists such as Stanislas Dehaene.Clinical neurologist and skeptic Steven Novella has dismissed it as "the hard non-problem".


Formulation of the problem

Chalmers' formulation   
▪ In Facing Up to the Problem of Consciousness (1995), Chalmers wrote:

It is undeniable that some organisms are subjects of experience. But the question of how it is that these systems are subjects of experience is perplexing. Why is it that when our cognitive systems engage in visual and auditory information-processing, we have visual or auditory experience: the quality of deep blue, the sensation of middle C? How can we explain why there is something it is like to entertain a mental image, or to experience an emotion? It is widely agreed that experience arises from a physical basis, but we have no good explanation of why and how it so arises. Why should physical processing give rise to a rich inner life at all? It seems objectively unreasonable that it should, and yet it does.

In the same paper, he also wrote:

The really hard problem of consciousness is the problem of experience. When we think and perceive there is a whir of information processing, but there is also a subjective aspect.

The philosopher Raamy Majeed noted in 2016 that the hard problem is, in fact, associated with two "explanatory targets"

▪ [PQ] Physical processing gives rise to experiences with a phenomenal character.
▪ [Q] Our phenomenal qualities are thus-and-so.

The first fact concerns the relationship between the physical and the phenomenal, whereas the second concerns the very nature of the phenomenal itself. Most responses to the hard problem are aimed at explaining either one of these facts or both.



Easy problems

Chalmers contrasts the hard problem with a number of (relatively) easy problems that consciousness presents. He emphasizes that what the easy problems have in common is that they all represent some ability, or the performance of some function or behavior.

Examples of easy problems include
the ability to discriminate, categorize, and react to environmental stimuli;
the integration of information by a cognitive system; the reportability of mental states;
the ability of a system to access its own internal states; the focus of attention; the deliberate control of behavior; the difference between wakefulness and sleep.


Other formulations

Other formulations of the "hard problem" include:

"How is it that some organisms are subjects of experience?"
"Why does awareness of sensory information exist at all?"
"Why do qualia exist?"
"Why is there a subjective component to experience?"
"Why aren't we philosophical zombies?"

Historical predecessors

▪ The hard problem has scholarly antecedents considerably earlier than Chalmers, as Chalmers himself has pointed out.

▪ The physicist and mathematician Isaac Newton wrote in a 1672 letter to Henry Oldenburg:

to determine by what modes or actions light produced in our minds the phantasm of colour is not so easie.

▪ In An Essay Concerning Human Understanding (1690), the philosopher and physician John Locke argued:

Divide matter into as minute parts as you will (which we are apt to imagine a sort of spiritualizing or making a thinking thing of it) vary the figure and motion of it as much as you please—a globe, cube, cone, prism, cylinder, etc., whose diameters are but 1,000,000th part of a gry, will operate not otherwise upon other bodies of proportionable bulk than those of an inch or foot diameter—and you may as rationally expect to produce sense, thought, and knowledge, by putting together, in a certain figure and motion, gross particles of matter, as by those that are the very minutest that do anywhere exist. They knock, impel, and resist one another, just as the greater do; and that is all they can do... [I]t is impossible to conceive that matter, either with or without motion, could have originally in and from itself sense, perception, and knowledge; as is evident from hence that then sense, perception, and knowledge must be a property eternally inseparable from matter and every particle of it.

▪ The polymath and philosopher Gottfried Leibniz wrote in 1714, as an example also known as Leibniz's gap:

Moreover, it must be confessed that perception and that which depends upon it are inexplicable on mechanical grounds, that is to say, by means of figures and motions. And supposing there were a machine, so constructed as to think, feel, and have perception, it might be conceived as increased in size, while keeping the same proportions, so that one might go into it as into a mill. That being so, we should, on examining its interior, find only parts which work one upon another, and never anything by which to explain a perception.

▪ The philosopher and political economist J.S. Mill wrote in A System of Logic (1843), Book V, Chapter V, section 3

Now I am far from pretending that it may not be capable of proof, or that it is not an important addition to our knowledge if proved, that certain motions in the particles of bodies are the conditions of the production of heat or light; that certain assignable physical modifications of the nerves may be the conditions not only of our sensations or emotions, but even of our thoughts; that certain mechanical and chemical conditions may, in the order of nature, be sufficient to determine to action the physiological laws of life. All I insist upon, in common with every thinker who entertains any clear idea of the logic of science, is, that it shall not be supposed that by proving these things one step would be made towards a real explanation of heat, light, or sensation; or that the generic peculiarity of those phenomena can be in the least degree evaded by any such discoveries, however well established. Let it be shown, for instance, that the most complex series of physical causes and effects succeed one another in the eye and in the brain to produce a sensation of colour; rays falling on the eye, refracted, converging, crossing one another, making an inverted image on the retina, and after this a motion—let it be a vibration, or a rush of nervous fluid, or whatever else you are pleased to suppose, along the optic nerve—a propagation of this motion to the brain itself, and as many more different motions as you choose; still, at the end of these motions, there is something which is not motion, there is a feeling or sensation of colour. Whatever number of motions we may be able to interpolate, and whether they be real or imaginary, we shall still find, at the end of the series, a motion antecedent and a colour consequent. The mode in which any one of the motions produces the next, may possibly be susceptible of explanation by some general law of motion: but the mode in which the last motion produces the sensation of colour, cannot be explained by any law of motion; it is the law of colour: which is, and must always remain, a peculiar thing. Where our consciousness recognises between two phenomena an inherent distinction; where we are sensible of a difference which is not merely of degree, and feel that no adding one of the phenomena to itself would produce the other; any theory which attempts to bring either under the laws of the other must be false; though a theory which merely treats the one as a cause or condition of the other, may possibly be true.

The biologist T.H. Huxley wrote in 1868:

But what consciousness is, we know not; and how it is that anything so remarkable as a state of consciousness comes about as the result of irritating nervous tissue, is just as unaccountable as the appearance of the Djin when Aladdin rubbed his lamp in the story, or as any other ultimate fact of nature.

The philosopher Thomas Nagel argued in 1974:

If physicalism is to be defended, the phenomenological features must themselves be given a physical account. But when we examine their subjective character it seems that such a result is impossible. The reason is that every subjective phenomenon is essentially connected with a single point of view, and it seems inevitable that an objective, physical theory will abandon that point of view.
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