Toward a Neuroethics of Pain Medicine
The Neurophenomenology of Pain: Mechanisms, Meaning, and Morality
An enhanced understanding of neuroscience, together with a broadened notion of mind, has instigated pragmatic and ethical concerns about the experience of pain. Such concerns must account for both the neural process of pain and its proximate and more durable effects—as neural event and experience—on cognitive, emotional, and behavioral effects that occur in painient beings existing within particular environments, communities, and cultures. The experience of pain occurs through the activation of hierarchical networks that may vary as a consequence of geno-phenotype-environmental interactions over time in each individual.1,2 Edelman’s concept of environmentally- and developmentally-dependent and variable functional and structural plasticity of peripheral and central nervous systems—as well as “top-down” effects that such plasticity incurs—reflects the sensitivity of these substrates to changes induced by internal and/or external conditions.3-6
This construct underscores the newly popular catchphrase of “…see one brain, see one brain,” and in light of this it is likely that the sensation and experience of pain are individually variant, subjective, and knowable only to the one in pain. In essence, we cannot know what it is like to be another being7; rather we can only recognize or know others’ experiences in relation to our own subjectivity.8,9 We do this by 1) objectifying others’ experiences by applying intellectual knowledge of common processes that are equivalent or similar in ourselves and others (i.e.- phenomenological relativism), 2) perception of some set of knowable reactions, responses and/or semiotics, and/or 3) the direct explanation of subjective experience(s) by others. This makes pain assessment pragmatically and morally difficult in those situations in which linguistic and/or communicative barriers exist—such as between cultures—when dealing with patients who are profoundly mentally impaired, demented, or obtunded, and when dealing with animals.10
The Possibilities and Limitations of Neuroscience and Neurotechnology
Knowledge of the development, structure, and function of the neural systems that mediate pain and analgesia is vital, but it is equally important to recognize how and why such objective information contributes to, and “fits” into, a contextual understanding of 1) how these systems interact with various environments to create first-person experience(s), and 2) how to deal with the uncertainty of others’ subjective experience.
The imperative to evaluate and treat pain and suffering has been a major incentive for the development of new medical techniques and technologies.11 Science and technology have allowed a more thorough understanding of neural systems, brain-mind, concepts of “self,” and pain. Perhaps neurotechnology will one day allow the completely objective assessment of pain (and its experience). To date, however, this has not been the case and, even if this were possible, we still must confront the limitations, burdens, and risks—as well as the benefits—of any technology. Scientific advancements should not be divorced from the responsibilities to use these developments and the information they deliver in ways that are both technically right and morally sound.12-14
Current neuroscience, as a consilient field, affords the most complete account of the relationship of brain, mind, and self—yet neuroscientific knowledge informs that these relationships are not linear nor wholly deterministic and we are forced to recognize and confront the boundaries of neuroscientific understanding.15 Our knowledge of the nervous systems of various organisms—and of the human organism at various stages and states of existence—allows, or perhaps more accurately compels, consideration that particular organisms can feel pain.16,17 That an organism has the capacity to feel pain should both sustain our (third person) belief that they experience pain, and guide our treatment of pain and suffering in accordance with some form of precautionary principle.
This neuroscientific orientation may be sufficient to ground an overarching obligation to treat pain. To be sure, neuroscience has lent considerable insight to how pain can alter the brain to affect the mind and self, the nature of suffering (and empathy), and the role of brain-mind in healing. But we must ask whether these explanatory models effectively represent the existential predicament of pain and suffering and if such explanations can guide the ethical decisions that arise in the care of pain as disease and/or illness. If the core incentive of neuroscientific inquiry is not simply knowledge “for knowledge’s sake,” but the acquisition of knowledge that can be applied toward the achievement of an identifiable, humanitarian purpose, then moral consideration is required to determine “why” and “how” care must be rendered so as to ethically enact pain medicine as an individual and social good.18
A Neuroethics of Pain Medicine: Purpose and Potential
This speaks to the need for an ethics that both reflects, and is directly relevant to, the current neuroscience of pain, the person as sentient being, culture(s), and healing; in other words, a neuroethics of pain medicine. Such a neuroethics must be construed in both the European tradition—as the neural basis for, and of, moral decision-making—and the American tradition—as the moral basis and ethics of neuroscientific research, applications, and related practice(s).19 This may ground pain care to a naturalistic (neuro)philosophy that allows, if not fortifies, acknowledgment of the capacity to experience pain as a quality of intrinsic moral gravitas. But this neurophilosophy also incurs ethical issues that arise directly from the intersection of neuroscience, pain medicine, and society.
For example, the principle of respect for autonomy has played a central role in much of contemporary bioethical thought, based upon varying constructs of the “self.”20 In the strictest sense, autonomy can be understood to be 1) a particular kind of potentiality of being, 2) the ability of such a being to make independent decisions and actions, and 3) the negative right of refusal.21 Autonomy in the first sense (i.e.- a being as an autonomous moral subject) is in some ways related to the manifestations of a being’s independent decisions and actions.22
But who (or what) is a moral subject? What of those circumstances in which the level of neural function makes a being unable to act autonomously? This often occurs because of individuals’ immaturity (e.g.- neonates, young children), not being fully conscious, or being mentally impaired. Very often, these individuals also cannot express their sentience or pain. Because of this, should we not regard pain in the very young, very old, and the very sick? And what of non-human pain? Probably, like never before, an understanding of animal nervous systems has allowed a consideration of the possibility of pain equivalence in animals—if not of animal minds more broadly—and this latter possibility has initiated dispute about previously held notions of consciousness, mentation, autonomy, and moral value.23-25