Abstract

DIAZ, José Luis. La identidad del dolor; ¿lesión, congoja, lamento o neuromatríz?. Salud Ment [online]. 2005, vol.28, n.2, pp.13-32. ISSN 0185-3325.

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.

Keywords : Pain; consciousness; perception; phenomenology; qualia; second-person epistemology; dual aspect theory.

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