Self and World: the case of Pain

The International Association for the Study of Pain (IASP) defines pain as ‘an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage’ (Merskey & Bogduk, 1994). The IASP definition of pain is unique in that it explicitly recognizes that pain is an experience that can be understood in itself, in an internal way, in contrast to prior definitions (Sternbach, 1968; Mountcastle, 1974) that defined pain in terms of external causal stimuli that are correlated in some way with pain feelings and sensations.

External characterizations of pain based on neuroscientific findings remain influential in the pain literature. For example, according to a leading theory, pain feelings and sensations are externally related to a brain image of the ‘afferent representation of the physiological condition of the body’ (Craig, 2003). Interpreted philosophically, this view of pain is analogous to the traditional rational-metaphysical presupposition that feelings are but ‘sensations or emotions of the soul which are related especially to it,’ as Descartes put it, and thus are features only of the self and not of the world.

But pain is not only a personal feeling adhering to the self but that through my pain I am connected to a felt reality of the world. This world is not a world of causal reasons but a world that tonally flows in a certain direction and manner (Smith, 1986). When a sharp object is painfully cutting me, I experience a feeling of wincing back and away from the object, and in correlation with this feeling-flow the sharp object is felt to have a tonal-flow of flowing forwards, towards and into me in a piercing manner. When pain makes me fearful, I experience a feeling-flow of retreating backwards and away from the existent that is threatening me. The feeling flows backwards in a shrinking and cringing manner; I have the sensation of ‘shrinking and cringing back from’ the threatening existent. When my pain presents the quality of anxiety, my experience does not flow backwards as a ‘retreat from’, but has the directional sense of being suspended over an inner bottomlessness. The feeling flow of anxiety during pain is a flow that hovers before the possibility of flowing in a downward direction. When pain presents angry retaliation, I feel an angry ‘striking back’ towards the pain-affected body-part, and as such flows forwards, towards the limb at which I am angry. It flows forwards in a violently attacking manner. By virtue of correlated tonal and painful flows, the world and I are joined together in an extrarational and sensuously appreciative way.

Instead of only describing the external things to which pain is externally related, it is also possible to describe pain internally by noting other internal determinations of the feelings and sensations with which it is united. Joint internal-external characterizations of pain very roughly map onto neuroscientific evidence showing that our cutaneous nociceptive system differentiates into interoceptive and exteroceptive causal features, such that our interoceptive nociceptive system signals tissue disorders that are inescapable, and causes homeostatic responses, and our exteroceptive nociceptive system extracts meaningful information about events in the world in order to effect behaviors that protect the organism from external threats (Price et al. 2003).

References
Craig AD (2003). A new view of pain as a homeostatic emotion. Trends in neurosciences 26(6): 303–307.

Merskey H, Bogduk N (Eds) (1994). Classification of Chronic Pain (Second Ed.). IASP Press: Seattle, pp 209–214.

Mountcastle VB (1974). Pain and temperature sensibilities. Medical Physiology 13(1): 348–391.

Price DD, Greenspan JD, Dubner R (2003). Neurons involved in the exteroceptive function of pain. Pain, 106(3), 215–219.

Smith Q (1986).The felt meanings of the world: A metaphysics of feeling. Purdue University Press.

Sternbach RA (1968). Pain: A psychophysiological analysis. Academic Press: New York.

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An approach to understanding fetal pain and consciousness

The trend in the literature on fetal pain is to approach the question of consciousness in the fetus in terms of conscious states of pain. That is, first define what makes a pain a conscious mental state, and then determine being a conscious fetus in terms of having such a state. Thus, the possibility of a conscious fetus is thought to rely on theories of conscious pain states. Call this the state approach to fetal pain. 

Two state approaches to fetal pain are present in the literature. One approach looks at the brain structure(s), pathways and circuits necessary for conscious pain states and then seeks to establish whether this substrate is present and functional in the fetus. There is broad agreement among researchers that the minimal necessary neural pathways for pain are in the human fetus by 24 weeks gestation [1, for review]. Some researchers argue that the fetus can feel pain earlier than 24 weeks because pain is enabled by subcortical brain structures [4,5,6].

Another phenomenal approach is to consider the subjective content of a conscious experience of pain, and to ask whether that content might be available to the fetus [1,2,3]. Based on this approach, some researchers argue that the fetus cannot feel pain at any stage because it lacks developmental abilities and concepts such as sense of self necessary for pain [1,2,3].

Although both state approaches are presented as opposites in the literature, they share the determination of fetal pain based on specific levels or degrees of complexity, whether of the brain structures and the relationship they have to the conscious state of pain, or of the subjective contents that constitute that state.

An alternate approach to understanding fetal consciousness that has not been explored in the literature on fetal pain is the extent to which pain is based on the arrangement of certain brain structures (or experiential contents), rather than a result of maturation or increase in complexity achieved by growth of the brain substrate which below a certain size does not enable consciousness [7,8]. Thus, whether the fetus is excluded in this regard is not due to its simplicity, but because its lack of certain brain arrangements necessary to enable consciousness.

According to this alternate view of fetal pain, a living creature’s subjective contents may differ greatly in complexity. To convey the range of conscious possibilities, consider the Indian ‘scale of sentience’ (cited in [8]):

‘This.’
‘This is so.’
‘I am affected by this which is so.’
‘So this is I who am affected by this which is so.’

The possibilities in this consciousness scale range from simply experienced sensation (‘This’; ‘This is so’) to self-consciousness (‘I am affected by this which is so’; ‘So this is I who am affected by this which is so’). Each stage in this scale presupposes consciousness. Any experience, whatever its degree of complexity, is conscious. It follows that to see, to hear, and to feel is to be conscious, irrespective of whether in addition a creature is self-conscious that it is seeing, hearing, and feeling [7]. To feel pain is to be conscious of that experience regardless of whether in addition one is self-conscious of being in pain. Self-consciousness is just one of many contents of consciousness available to big-brained living creatures with complex capacities: it is not definitive of consciousness [7,8]. The point of saying this is that it circumvents the logical mistake of misidentifying attributes unique to a specialized form of consciousness (e.g., self-consciousness) as general features of consciousness itself.

With this alternate view of consciousness now sketched in, we should determine where the fetus and where pain fall in the Indian scale of sentience. The possibilities in the scale extend from mere sensation to self-consciousness–where does the fetus fall in?

References

[1] Derbyshire S, Raja A. (2011). On the development of painful experience.Journal of Consciousness Studies18, 9–10.

[2] Derbyshire SW. (2006). Controversy: Can fetuses feel pain?. BMJ: British Medical Journal332(7546), 909.

[3] Szawarski Z. (1996). Do fetuses feel pain? Probably no pain in the absence of “self”. BMJ: British Medical Journal313(7060), 796–797.

[4] Anand KJ, Hickey PR. (1987). Pain and its effects in the human neonate and fetus. New England Journal of Medicine317(21), 1321–1329.

[5] Anand KJ. (2007). Consciousness, cortical function, and pain perception in nonverbal humans. Behavioral and Brain Sciences30(01), 82–83.

[6] Lowery CL, Hardman MP, Manning N, Clancy B, Whit Hall R, Anand KJS. (2007). Neurodevelopmental changes of fetal pain. In Seminars in perinatology (Vol. 31, No. 5, pp. 275–282).

[7] Merker B. (1997). The common denominator of conscious states: Implications for the biology of consciousness. Available at: http://cogprints.soton.ac.uk.

[8] Merker B. (2007). Consciousness without a cerebral cortex, a challenge
for neuroscience and medicine. Target article with peer commentary and author’s response. Behavioral and Brain Sciences, 30, 63–134.

Pain experience and the self

Conscious pain is always personal. It is experienced from the view of oneself, and is not real or meaningful apart from this perspective.

All pains cluster around one’s personal aperture as around a single point or origin from which they are all perceived, irrespective of where in the body pain is felt. The sensation of a pain in a hand is sensed as located in the hand, but that pain sensation in the hand is not felt from the hand, but from about the same spatial location from which that hand is personally seen, even if pain is felt in complete darkness or in a dream. It is the ‘here’ with regard to which any pain is ‘there.’

It may intuitively feel that this single experiential point is located at the mid-point between the centers of rotation of the two eyes. Mach’s drawing above shows a monocular view of this point given in peripheral vision. In fact, the empirically determined location of the point is deeper inside the head, in the midsagittal plane, roughly 4–5 cm behind the bridge of the nose. Initially developed by Herring (1879/1942), this determination identifies the intersection of a few lines of sight obtained by fixating certain locations in the environment and aligning pins with them along each of the lines of sight or attention.

The self thus located is the origin of all lines of sight/attention and so cannot be any kind of self-representation (Merker, 2007, 2013). It defines the view point from which any and all representations of sensory experience are perceived, including personal pain. It is the point from which attention is directed and relative to which percepts are located in the space whose origin it defines (Merker, 2007, 2013).

To think that self must involve a kind of self-representation is to transfer sensory experience from the sensory state to one of its sub-domains (the self), which I think motivates viewing the self as a kind of cartesian homunculus. On this cartesian view, pain is interpreted in presence of the self. To my mind, it seems the other way round: the self in pain finds itself in the presence of pain (the ‘content’ of pain). The self of any conscious pain is not inherently conscious. Pain is intruder, not self. That is why pain is an aversion.

From this single experiential point we look out upon the world along straight and uninterrupted lines of sight. This orientation is dramatically reversed in the experience of pain. During pain, attentional focus is rapidly and involuntarily moved backwards along these same lines toward their most proximal origin. I believe this reverse direction helps to characterize the meaning of conscious pain as intrusion or threat to oneself.

References

Hering, E. (1879/1942). Spatial Sense and Movements of the Eye. Trans. C. A. Radde. Baltimore, MD: American Academy of Optometry (Original work published in 1879).

Mach, E. (1897). Contributions to the Analysis of the Sensations. La Salle, IL: Open Court.

Merker, B. (2007). Consciousness without a cerebral cortex, a challenge
for neuroscience and medicine. Target article with peer commentary and author’s response. Behavioral and Brain Sciences, 30, 63–134.

Merker, B. (2013). The efference cascade, consciousness, and its self: naturalizing the first person pivot of action control. Frontiers in Psychology, doi:10.3389/fpsyg.2013.00501.