ABSTRACT
resumen está disponible en el texto completo
Abstract: The present paper offers a particular emergence, dual aspect, and dynamic system theory of the neural correlate of consciousness. The theory is grounded on two successive hypotheses supported with empirical evidences and concepts from the neurosciences, approximations to the sciences of complexity, and philosophical arguments. The first hypothesis is that consciousness emerges along with the highest level of brain function, i.e., at the intermodular domain of the whole organ. This hypothesis is upheld by two necessary requisites; the first is the generalized impression in neuroscience of the brain as an information-handling device, and that this property enables every mental activity, including consciousness, to take place. This concept is verified on several empirical grounds. If we take the synapse as a binary code of information, the computation capacity of the brain is in the order of 100 million Megabits. Even such enormous figure is limited and misleading because the synapse manifests not only two, but three possible informational states (excitation, rest, and inhibition), because there are subliminal potentials, and also a compact intracellular information machinery. Moreover, the informational requirement of consciousness is accurately delivered by Kuffler and Nichols' five ruling principles of brain function: (1) The brain uses electrical signals to process information; (2) Such electrical signals are identical in all neurons; (3) The signals constitute codes of codification and representation; (4) The origin and destiny of the fibers determines the content of information; (5) The meaning of the signals lies in the interactions. Even though the reference to representation, content, and meaning implies higher cognitive properties, it seems necessary to add a sixth principle for a more judicious neural implication in regard to consciousness. This principle is that information is processed in the brain in six levels of complexity, undergoing a gradual gain in density, integration, congruity, and capacity in each consecutive stratum. The six levels are the following: (1) Organismic, the integration of the nervous system with the rest of the organism systems; (2) Organic, the integration of the different modules in the whole brain; (3) Modular, the set of brain modules and their interconnections; (4) Intercellular, the designs and functional bindings among neuron cells; (5) Cellular, the set of brain cells, particularly neurons; (6) Molecular, the chemical components that mediate the transmission of information. In this fashion, the second requisite to uphold the emergence of consciousness lies in establishing that the different levels of brain organization constitute a pyramidal arrangement. Certainly, the number of elements is greater in the lower levels, while the integration of information is progressively enhanced in the upper levels. Moreover, this neuropsychological pyramid insinuates both an ascending cascade whereby the lower orders stipulate and influence the upper ones, and a progressive and convergent functional enrichment ultimately resulting in the qualia, feeling, and awareness attributes of consciousness. Information flows horizontally in each level, but it also overflows vertically in both directions. This pyramidal scheme is applied to clarify two parti cular aspects of brain function that are closely linked to consciousness: the electrical activity and the engram of memory. Such inquiry makes clear that a qualitative jump manifested by the emergence of various and dissimilar novelties occur at each layer of brain operation based upon a mass coordination. It seems feasible to envision the engram, and conceivably every other mental representation, as a plastic pattern involving all levels and aspects of brain operation, including the pinnacle where consciousness consolidates as the subjective aspect of the uppermost brain function. As a result of the proposed stratified and pyramidal scheme of brain functions, the first hypotheses is strengthened and specified. Thus, presumably consciousness and the neural capacities correlated to it constitute two associated aspects emerging from such particular functional hierarchy at the organic level of the brain by the efficient connection of its modules. It would not be required that all the modules of the brain become interrelated during a conscious processing, but that they would be functionally available while some of them become progressively active by intermodular articulation thereby making possible the arising and unfolding of conscious mental operation streams. In order to reinforce this notion the visual system is invoked since the scene that is consciously perceived emerges from the coordination of some 40 modules that separately appear to operate unconsciously. At the moment that such high-hierarchy and complex function presumably appears, it would achieve a conscious correlate and become altogether able to exert a descending causality and supervene the operation of the lower orders, which, among other capacities, would permit voluntary action to take place. In order to specify the first hypothesis asserting that consciousness emerges at the organic level of the brain along with the proficient inter-modular connectivity, a second hypothesis is formulated and justified in neuroanatomical, neurophysiological, and complexity science terms. The supposition is that the specific neural correlate of consciousness may be a function similar to a bird flock or an insect swarm orderly binding the operations of different modules in a cinematic, hipercomplex, coherent, and synchronic stream. The human brain contains some 400 cortical and subcortical modules functioning as partially specialized stations that potentially interchange particularly codified information through some 2500 fibers or intermodular pathways. The hypothesis requires that information complexity undergoes a further and substantial gain of attributions through the concise and prolific connectivity of the different modules. In this regard, it is supposed that a stream of coherent activation is constituted in the conscious brain by the intermodular dynamics and that such dynamics may acquire global patterned properties in a simi lar way as bird flocks and so-called intelligent swarms achieve unanimously shifting dynamics. This particular idea is supported with complexity science models of the remarkable performances of large groups of birds and insects and with the known behavior of massive populations of neurons. In so far as this would be a complex function operating at the limits of equilibrium resulting from local dynamics of the brain subsystems, the self-organization of high level brain functions justifies the notion that a dynamic coupling among modules can and may result in complex cognitive properties and consciousness. Intermodular brain dynamics is conceived here as an emergent, unbound, synchronic, hypercomplex, highly coherent, and tetradimensional process capable to navigate, steer, swirl, split, and flow throughout the brain and thereby connect very diverse systems in a fast and efficient manner. In the same way, its putative subjective correlate, the conscious process, can be conceived as an emergent, voluntary, unified, qualitative, and narrative process capable to access, coordinate, and integrate multiple local information mechanisms. The hypothesis poses that the conscious transformation of information is correlated, moment to moment and point to point, with the intermodular processing that evolves in the manner of a bird flock or swarm dynamics. It is finally posed that brain intermodular dynamics correlated to consciousness consolidates by the convergence of an ascending bottom-up organization of the different ranks of brain operation, and by the descending top-down influx of the social, cultural, and environmental information where the individual is immersed.
ABSTRACT
resumen está disponible en el texto completo
Abstract: The present paper offers a particular emergence, dual aspect, and dynamic system theory of the neural correlate of consciousness. The theory is grounded on two successive hypotheses supported by empirical evidences and concepts from the neurosciences, approximations to the sciences of complexity, and philosophical arguments. The first hypothesis is that consciousness emerges along with the highest level of brain function, i.e., at the intermodular domain of the whole organ. This hypothesis is upheld by two necessary requisites. The first is the generalized impression in neurosciences of the brain as an information-handling device, and that this property enables every mental activity, including consciousness. This concept is verified on several empirical grounds. If we take the synapse as a binary code of information, the computation capacity of the brain is in the order of the 100 million megabits. Even such an enormous figure is limited and misleading because the synapse manifests not only two, but three possible informational states (excitation, rest, and inhibition), because there are subliminal potentials, and also a compact intracellular information machinery. Moreover, the informational requirement of consciousness is accurately delivered by Kuffler and Nichols' five ruling principles of brain function: 1. The brain uses electrical signals to process information; 2. such electrical signals are identical in all neurons; 3. the signals constitute codes of codification and representation; 4. the origin and destiny of the fibers determines the content of information; 5. the meaning of the signals lies in the interactions. Even though the reference to representation, content, and meaning implies higher cognitive properties, it seems necessary to add a sixth principle for a more judicious neural implication in regard to consciousness. This principle is that information is processed in the brain in six levels of complexity, undergoing a gradual gain in density, integration, congruity, and capacity in each consecutive stratum. The six levels are the following: 1. organismic, the integration of the nervous system with the rest of the organism systems; 2. organic, the integration of the different modules in the whole brain; 3. modu lar, the set of brain modules and their interconnections; 4. intercellular, the designs and functional bindings among neuron cells; 5. cellular, the set of brain cells, particularly neurons; 6. molecular, the chemical components that mediate the transmission of information. In this fashion, the second requisite to uphold the emergence of consciousness lies in establishing that the different levels of brain organization constitute a pyramidal arrangement. Certainly, the number of elements is greater in the lower levels, while the integration of information is progressively enhanced in the upper levels. Moreover, this neuropychological pyramid insinuates both an ascending cascade whereby the lower orders stipulate and influence the upper ones, and a progressive and convergent functional enrichment ultimately resulting in the qualia, feeling, and awareness attributes of consciousness. Information flows horizontally in each level, but it also overflows vertically in both directions. This pyramidal scheme is applied to clarify two parti cular aspects of brain function that are closely linked to consciousness: the electrical activity and the engram of memory. Such inquiry makes clear that a qualitative jump manifested by the emergence of various and dissimilar novelties occur at each layer of brain operation based upon a mass coordination. It seems feasible to envision the engram, and conceivably every other mental representation, as a plastic pattern involving all levels and aspects of brain operation, including the pinnacle where consciousness consolidates as the subjective aspect of the uppermost brain function. As a result of the proposed stratified and pyramidal scheme of brain functions, the first hypotheses is strengthened and specified. Thus, presumably consciousness and the neural capacities correlated to it constitute two associated aspects emerging from such particular functional hierarchy at the organic level of the brain by the efficient connection of its modules. It would not be required that all the modules of the brain became interrelated during a conscious processing, but that they would be functionally available instead, while some of them become progressively active by intermodular articulation, thereby making possible the arising and unfolding of conscious mental operation streams. In order to reinforce this notion, the visual system is invoked since the consciously perceived scene emerges from the coordination of some 40 modules that separately appear to operate unconsciously. At the moment that such high-hierarchy and complex function presumably appears, it would achieve a conscious correlate and become altogether able to exert a descending causality and supervene the operation of the lower orders, which, among other capacities, would permit voluntary action to take place. In order to specify the first hypothesis, asserting that consciousness emerges at the organic level of the brain along with the proficient intermodular connectivity, a second hypothesis is formulated and justified in neuroanatomical, neurophysiological, and complex scientific terms. The supposition is that the specific neural correlate of consciousness may be a function similar to a bird flock or an insect swarm orderly binding the operations of different modules in a cinematic, hipercomplex, coherent, and synchronic stream. The human brain contains some 400 cortical and subcortical modules functioning as partially specialized stations that potentially interchange particularly codified information through some 2500 fibers or intermodular pathways. The hypothesis requires information complexity undergoing a further and substantial gain of attributions through the concise and prolific connectivity of the different modules. In this regard, it is supposed that a stream of coherent activation is constituted in the conscious brain by the intermodular dynamics and that such dynamics may acquire global patterned properties in a simi lar way as bird flocks and so-called intelligent swarms achieve unanimously shifting dynamics. This particular idea is supported with complex scientific models of the remarkable performances of large groups of birds and insects and with the known behavior of massive populations of neurons. In so far as this would be a complex function operating at the limits of equilibrium resulting from local dynamics of the brain subsystems, the self-organization of high level brain functions justifies the notion that a dynamic coupling among modules may result in complex cognitive properties and consciousness. Intermodular brain dynamics is conceived here as an emergent, unbound, synchronic, hypercomplex, highly coherent, and tetradimensional process capable to navigate, steer, swirl, split, and flow throughout the brain and thereby connect very diverse systems in a fast and efficient manner. In the same way, its putative subjective correlate -the conscious process- may be conceived as an emergent, voluntary, unified, qualitative, and narrative process capable to access, coordinate, and integrate multiple local information mechanisms. The hypothesis poses that the conscious transformation of information is correlated, moment to moment and point to point, with the intermodular processing that evolves in the manner of a bird flock or swarm dynamics. It is finally posed that brain intermodular dynamics correlated to consciousness consolidates by the convergence of an ascending bottom-up organization of the different ranks of brain operation, and by the descending top-down influx of the social, cultural, and environmental information where the individual is immersed.
ABSTRACT
resumen está disponible en el texto completo
Abstract: This article formulates a perceptual and representational theory of pain that requires a second-person epistemology that is optimally compatible with a dual aspect theory of consciousness calling for progressive psychophysical correlations. The identity of pain, taken as a peculiar state of consciousness, is explored in physiological, phenomenological, epistemological, and ontological terms. At the same time, and following the leads of philosophers of mind, pain is used to stipulate and examine the main current mind-body theories. The current definitions are unsatisfactory because it is not possible to identify the nature of pain with words beyond asserting that it is an unpleasant sensation resulting from a body injury. The usual definitions of pain accept that it is a conscious phenomenon that has well-established physiological foundations, except for its precise brain representation. Indeed, the phenomenological physiology of pain is known from the nociceptive receptors, the peripheral pathways and their central relays up to the thalamus and cerebral cortex. The somatosensory cortex, parieto-limbic, and anterior cingular sections of the cortex are involved in the central neuromatrix of pain, a concept that entails a functional binding among different sensory, cognitive, affective and volitional areas necessarily involved in the central representation of pain. A purely sensorial conception of pain is incomplete because it usually constitutes a legitimate perception in the sense that pain is the conscious representation of a bodily lesion subjected to different degrees of appraisal, knowledge, and understanding. Furthermore, as it occurs with every perception, in the case of pain there are illusions (referred pain), hallucinations (phantom limb pain), cognitive influences (the analgesia of the athlete and soldier), semantic components and pathologies where stimulus and representation can be dissociated. Phantom limb pain suggests that receptors and peripheral signals do not only activate the neuromatrix, but that it activates itself generating a pain experience without external stimuli. Upon these physiological and cognitive bases it is proposed that pain is the subjective representation of a bodily injury. The representation is composed of six different aspects: the sensitive (quale of pain sensation), affective (aversive and disturbing emotion), cognitive (recognition of the lesion), volitional(intending the actions), behavioral (movement, gesture, exclamation), and cultural (modulation according to beliefs and social learning of rules). The different components are linked in different ways to construct a complex representation where each one appears as physical and mental, neurophysiological and conscious. Different combinations of the various elements are the bases to build a medical taxonomy in classes such as "angina," "migraine," "colic," "trigeminal neuralgia," "lumbago," or "radicular pain." The spatial location of pain is baffling because even though it is referred to the site of the lesion, the neuroscience concept is that it is not there, but in the brain, creating an incongruity between phenomenological experience and scientific evidence. The perceptual and representational theory of pain solves this discrepancy but also opens the possibility that consciousness may cover more bodily territory than a restricted neuromatrix. The phenomenology of pain is difficult to establish because painful qualia are ineffable. In order to explore the phenomenology of pain, the Diario del dolor (Journal of Pain) by Mexican writer María Luisa Puga is used in the present article. In this journal pain appears as a foreign and invasive factor producing fear and forcing consciousness to focus on the discomfort, incapable of habituation to the affliction. Multiple strategies to deal with pain are set in operation. Pain acquires a face, a body, and a personality. Accepting pain implies to conceptualize it as an enemy that can be understood and with whom is possible to confer. Self-consciousness deteriorates and the narrator dos not recognize herself in the mirror, she has lost past and future, there is only a present with pain. The existence has become insipid and it is necessary to deal with dejection, depression, and defeat. Finally pain is recognized as intrinsically human and Puga's Journal underlies that the private and lonely experience of pain that a person experiences using multiple coping strategies may result in considerable understanding and dignity. From such a first person perspective, pain is confirmed to be a very complex experience where consciousness kindles unusual faculties, demands extraordinary resources, and stages costly battles. The epistemology of pain can be tackled from first, second, and third person perspectives. Since the subjective nature of pain is insuperable, the essential core of pain is the private experience reclaimed and expressed as a symptom by a subject. Nevertheless, from such first person perspective it is possible to describe, analyze, and evaluate the experience with phenomenological tools. Third person perspective means to be objective about the subjective symptom and it takes recourse in semiology and pathological correlations in order to reach a diagnosis. Usually first and third person perspectives are taken to be unfitting. From a methodological point of view there is no contradiction between these two falsely separated perspectives since what normally occurs is a face to face interaction calling for a second person perspective. From this methodological position pain consciousness overflows towards another person and ceases to be a private phenomenon acquiring an expressive and communicative aspect between the patient and the analyst gathering information through dialog and anamnesis. The second person perspective is based on the solicitation of help, and relief in the part of the patient, and the provision of attention, care, compassion, and therapy in the part of the supporter. A second person perspective acquires meaning in the interview, consultation and face-to-face dialog so that an adequate understanding aims at the subjective well being even before the cure of the injury. The ontological identity of pain is analyzed in neurobiological terms and philosophical theories. Identity theory poses that pain is a specific physiological state, such as the activation of pain fibers, brain centers, or a neuromatrix that may be species-specific. Nevertheless the identity theory appears deficient since pain is general to many species with different nervous systems, and because there is an explanatory gap between phenomenological qualia and neurophysiological mechanism that remains obscure. The theory of emergence is also formulated and it becomes apparent that it is necessary to identify the nature of the emergent property in order to become testable. Finally dual-aspect theory is proposed as the most satisfactory to understand the nature of pain. This theory implies the emergence of a high level of nervous integration that, because of its inherent complexity acquires a subjective qualitative aspect. Even though the precise nature of the aspectual shape of pain also remains blurred, the theory heuristically calls for correlations and not a reduction between phenomenological and neurophysiological aspects of pain. Such correlations are open to continuous scientific exploration and they may constitute psychophysical laws. This formulation is compatible with the perceptual and representational theory of pain and it requires the methodological approach of the second person perspective.