Online research in philosophy

I address this talk to anyone who believes in the possibility of an informative empirical science about sensory qualities. Potentially this is a large audience. By "sensory quality" I mean those qualities manifest in various sensory experiences: color, taste, smell, touch, pain, and so on. We should include sensory modalities humans do not share, such as electro-reception in fish, echolocation in bats, or the skylight compass in birds. Those pursuing empirical science about this large domain might pursue it in the halls of experimental psychology, psycho-physics, psychometrics, psycho-physiology, sensory physiology, neuroscience, neuro-biology, comparative psychology, neuro-anatomy, and so on and on. These days even molecular genetics has kicked in with some notable recent contributions to the sequencing of genes for photopigments and for olfactory receptors. But to all those investigators in all those halls I bring bad news. Your discipline is _a priori_ impossible. Philosophers whom you do not know have uncovered _a priori_ proofs that empirical investigation which proceeds along the lines currently underway, or which will proceed along lines that are currently _imaginable_, does not, will not, and cannot explain the sensory qualities of experience. Or at least so they say. You might as well give up now.

Pain is an important focus for consciousness research because it is an avenue for exploring somatic awareness, emotion, and the genesis of subjectivity. In principle, pain is awareness of tissue trauma, but pain can occur in the absence of identifiable injury, and sometimes substantive tissue injury produces no pain. The purpose of this paper is to help bridge pain research and consciousness studies. It reviews the basic sensory neurophysiology associated with tissue injury, including transduction, transmission, modulation, and central representation. In addition, it highlights the central mechanisms for the emotional aspects of pain, demonstrating the physiological link between tissue trauma and mechanisms of emotional arousal. Finally, we discuss several current issues in the field of pain research that bear on central issues in consciousness studies, such as sickness and sense of self.

Pain is not a primitive sensory event but rather a complexperception and a process by which a person interacts with theinternal and external environments, constructs meaning, andengages in action. Because folk beliefs are central to meaning,folk concepts of pain play multiple causal roles in a painpatient's interaction with health care providers and others.In every case, the notion of pain is linked to a goal-directedbehavior that is useful to the person. The wide variation inconcepts of pain across individuals suffering with painunderscores the richness and complexity of the pain experience.In some cases involving chronic pain, the patient may form amaladaptive cluster of behaviors around the concept of pain.Patient beliefs and expectations are an important part of manychronic pain syndromes, and patients can benefit fromintervention directed at revising the individual's folk model of pain. Memetics offers a framework for identifying the memesthat patients hold and determining whether patient memes fitor clash with provider memes.

What follows raises objections to some arguments that claimthat a principle of applicability of ordinary pain talkconstrains developments in the pain sciences. A more apt pictureof lay use of pain language shows its non-theoretic character.Since instrumentalism and eliminativism are philosophical viewsabout the status of theories of pain, neither is a threatto clinical use of standard pain lingo. Perfected pain theoryis likely to enhance and improve pain language in clinicalsettings, should such theory find its way into popular ideasand talk of pain.

Our subjective sensory experiences are thought to be heavily shaped by interactions between expectations and incoming sensory information. However, the neural mechanisms supporting these interactions remain poorly understood. By using combined psychophysical and functional MRI techniques, brain activation related to the intensity of expected pain and experienced pain was characterized. As the magnitude of expected pain increased, activation increased in the thalamus, insula, prefrontal cortex, anterior cingulate cortex (ACC) and other brain regions. Pain-intensity-related brain activation was identified in a widely distributed set of brain regions but overlapped partially with expectation-related activation in regions, including the anterior insula and ACC. When expected pain was manipulated, expectations of decreased pain powerfully reduced both the subjective experience of pain and activation of pain-related brain regions, such as the primary somatosensory cortex, insular cortex, and ACC. These results confirm that a mental representation of an impending sensory event can significantly shape neural processes that underlie the formulation of the actual sensory experience and provide insight as to how positive expectations diminish the severity of chronic disease states.

One of the central assumptions made in much of contemporary philosophy of mind is that there is no appearance-reality distinction when it comes to sensory states. On this assumption, sensory states simply are as they seem: consciousness is an intrinsic property of sensory states—that is, all sensory states are conscious—and the consciousness of one’s own sensory states is never inaccurate. For a sensation to be felt as pain, for example, is for it to be pain. This assumption, which I call the Cartesian assumption, can be seen everywhere from the standard arguments against physicalism—such as those advanced by Kripke, Nagel, and Levine—to current theorizing about consciousness. I here argue that this assumption is false and that it goes wrong in two ways. I further argue that the appeal of the Cartesian assumption is due to a commitment many still have to a poorly motivated and misguided Cartesian model of consciousness and its relation to mental states. As an alternative to this Cartesian concept of mind, I argue for a theory of consciousness which claims that the “phenomenal character” of a sensation or perception—the “what it’s like” to have that sensation—is determined by the content of a higher-order thought one has of that sensory state.

An ethological analysis suggests that effort and protection actions, which are expressions of distress, are comparable with pain expressions. Distress occurs with uncontrollable pain, and the expressions are ritualized pain responses with exaggerated features and lower thresholds. Pain is a sensory-motor feeling state with aversive motivational (hedonic) value. Distress is an emotional state of failure of pain responses to control the pain.

When you suffer a pain are you suffering a sensation? An emotion? An aversion? Pain typically has all three components, and others too. There is indeed a distinct sensory system devoted to pain, with its own nociceptors and pathways. As a species of somesthesis, pain has a distinctive sensory organization and its own special sensory qualities. I think it is fair to call it a distinct sensory modality, devoted to nociceptive somesthetic discrimination. But the typical pain kicks off other processes too. For one it can grab your attention in a distinctive way, alerting you to its presence and sometimes obliging you to focus attention on the damaged member. Intense pain can eliminate your ability to think about anything else. Pain typically has direct and immediate motivational consequences: one wants it to stop, has an incentive to do whatever one can to reduce it, and is gratified by its termination. As these desires and motives collide with neural reality, emotional components of mental anguish, anxiety, and dread arise. The suffering involved in suffering from pain has multiple strands: it is not just the painfulness of the sensation, or the frustration of the desire that it end, but also the anguish over the possibility that it will never end, and the impossibility, if the pain is sufficiently intense, of focusing one’s attention on anything else.

The aim of this paper is to show that the empirical and conceptual constraints arising from the scientific research on pain phenomena should be taken into account in philosophical discussions concerning the nature and function of pain; otherwise, there is a good chance that philosophers will advocate too simplistic, confused or even outrightly mistaken theories or conceptions of pain. In order to prove this point, one of the most influential philosophical theories of pain—the so-called perceptual view of pain—is put to scrutiny in the light of the psychological, clinical and neurophysiological data coming from the field of pain research. More specifically, these data are presented in such a way as to show that the sensory quality or sensory aspect of pain is, contrary to the objectivistic claims of the perceptual view of pain, a necessary component of our total pain experience.