Proposal for PhD Thesis in Philosophy

 Thesis Title: Pain 

This research project contributes to the study of pain with reference to Wittgenstein’s philosophical psychology and pain facial expression. The thesis divides into five papers as follows: 

– Paper 1: Pretence and the definition of pain (approx. 20,000 words)

– Paper 2: Primitive pain-expression and deliberate control (approx. 20,000 words)

– Paper 3: The indeterminacy of pain (approx. 20,000 words)

– Paper 4: Is there a pain face? (approx. 20,000 words)

– Paper 5: Moebius Syndrome and pain catastrophizing (approx. 20,000 words) 

A description of each paper is below. 

Paper 1: Pretence and the definition of pain


The International Association for the Study of Pain (IASP) Committee for Taxonomy defines pain as ‘an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage’. They further state that ‘pain is always subjective. Each individual learns the application of the word through experiences related to injury in early life’ (Merskey, 1994).

This definition states that the employment of the word ‘pain’ needs to be learned through experiences in early life: a child has hurt himself and cries; and then adults talk to him and teach him the use (meaning) of ‘pain’. Wittgenstein (1958b) suggests that the child is trained to substitute its primitive, natural expressive pain-behavior first with exclamations and later with sentences such as ‘I have a stomach-ache’. There are other possibilities. One might point at someone who is manifestly in pain and say, ‘There: that is what it is to be in pain’, or ‘That is pain’ (see Wittgenstein, 1958b, §290). On the other hand, it appears that the perception of pain is an intrinsic feature of life itself, is manifested in all living organisms, and while subject to influence by life experiences, does not require previous experience in the first instance. The first experience of tissue injury is painful, in much the same way that touch, smell, vision, or hearing need not be learned in order to occur in the human being. Infants from 25 weeks gestation show a characteristic pain face consisting of eyes squeezed shut, brows lowered, deepening of the nasolabial furrow, open lips, with mouth stretched vertically and horizontally (Craig et al. 1993; Stevens et al., 1994).

The meaning of these sensations, however, will develop with experience through positive, negative, and contextual associations (Anand & Craig, 1996). In other words, learning cannot be separated from the behaving organism: ‘Only of living human being and what resembles (behaves like) a living human being can one say: it has sensations, it sees, is blind; is deaf; is conscious or unconscious’ (Wittgenstein, 1958, §218). As the person develops, so do its behavioral repertoire and the qualitative features of its subjective experiences. As characteristic features of the behaving organism, learning is incorporated into experience as components of a ‘form of life’ (Sullivan, 2001).

An adult, for example, can pretend to be in pain without saying a word, merely by facial expressions, torso movements, or paralinguistic qualities of speech (Wittgenstein, 1982, §944). But for these apparently simple behaviors to constitute pretence presupposes complex motives, intentions (e.g. the intention to deceive), as well as a complicated play of expressions (i.e. numerous nonverbal actions). Can one imagine a new-born child with the play of facial expressions and expressive-behavior of an adult? A new-born child cannot be insincere, but neither can he be sincere. To dissimulate pain, he must first learn to mimic and to intend to mimic (Wittgenstein, 1958b).

Available empirical evidence suggests that by the age of four children are able to use techniques to dissemble non-painful subjective states. This suggests that they may succeed in misrepresenting expressions of pain (Larochette et al., 2006). Cases of illness falsification have been reported in children as young as 8 years (Libow, 2000). Children report that their most common reason for using deception, especially to conceal physical pain in front of their peers, is a fear of negative consequences, and that controlling facial behavior is the most common method of regulating expressions of emotion (Zeman & Garber, 1996). This suggests that a child learns to dissimulate pain only in the course of learning the complicated interpersonal use of ‘having pain’ (Wittgenstein, 1982). He must learn not only ‘He has a pain’, but also ‘I think (believe) he has a pain’ and ‘He thinks I have a pain’ (Wittgenstein, 1980a).

Paper 2: Primitive pain-expression and deliberate control


Approaches to pain assessment typically distinguish between self-report and nonverbal, observational indices, but do not specify criteria or reasoning for the distinction (Hadjistavropoulos & Craig, 2002). Self-report indicators usually employ verbal report to describe the individual’s pain experience, or to communicate qualities of experience through the use of speech (e.g. ‘I have a dull nagging pain in my lumbar region’). The context is important as the exchange is either initiated by the individual in pain or serves as a response to others’ queries. Observational indicators typically focus upon nonverbal, publicly observable manifestations of pain including facial expressions, cry, limb and torso movements and paralinguistic qualities of speech.

The nonverbal behavior that is the focus of observational indices typically can be viewed as primitive in the sense that the behavior represents reflexive patterns of response to actual or impending tissue damage that are not anteceded by introspective awareness or inner observation of private phenomena (Wittgenstein, 1958b; 1980b; 1982). For example, babies’ cries typically alert mothers and caretakers as to children’s needs and initiate required care, even though the infant cannot be characterized as intending or consciously understanding the interaction. While pain is a powerful initiator of attention, introspection does not mediate or modulate primitive behavioral reactions. Instead, we claim that when conscious awareness is employed to influence any form of social communication, the expression cannot be taken as an automatic reaction pattern. For example, to pretend to be in pain, an individual must know how a person who is in pain behaves and focus one’s behavior on that model, intend to reproduce it (Wittgenstein, 1982). Moreover, people tend to experience difficulty suppressing nonverbal expressions of pain and there are subtle differences between spontaneous and feigned expressions of pain (Craig et. al, 1999).

Another important aspect of the primitiveness of pain communication pertains to the experience of conscious awareness of what is happening. Self-report indices typically necessitate attention to the task, including some degree of self-observation. By contrast, the behaviors included in many nonverbal indices occur spontaneously without prior awareness, although the individual likely will monitor the display (Hadjistavropoulos & Craig, 2002). This view ignores the important fact that self-report is used as a partial substitute for automatic nonverbal behaviors (Wittgenstein, 1958b). The exclamation ‘It hurts’, the groan ‘I have a stomach-ache’, the cry ‘I’ve hurt myself’ are reflexive patterns of response, not descriptions; they are comparable to automatic nonverbal behaviors rather than to reports such as ‘He has a back-pain’. In this situation, there is no such thing as my ‘finding out’ that I am in pain, or of my ‘attending’ or ‘recognizing’ my pain-sensations or experiences (Wittgenstein, 1958b).

A primitive expression of pain can be over-ridden to some degree. For instance, facial pain expression can be voluntarily controlled, although the upper face is less amenable to conscious control (Rinn, 1984). Communicative acts often reflect anticipation of consequences. As Wittgenstein (1958b) noted, pain behavior is deeply influenced by conditioning and learning. We claim that the more dependent pain behavior is on learning and conditioning, the more it will be subject to deliberate mediation. Empirical evidence suggests that nonverbal pain expressions that are genuine can be distinguished from masked or exaggerated expressions (Hadjistavropoulos et. al, 1996), possibly because of the greater automaticity of nonverbal expression places limits on the degree to which it can be influenced by learning and conditioning (in contrast to self-report). Observers generally appreciate this and communicate preferences for nonverbal behavior over verbal behavior when assessing the truthfulness of others’ pain behavior (Craig, Prkachin, & Grunau, 1992). This suggests that pain assessment presupposes behavioral manifestations, primarily nonverbal and observational indices, and that ascribing pain in others is possible only where we have criteria for identifying pain, which means that pain must be capable of being expressed (Wittgenstein, 1958b). 

Paper 3: The indeterminacy of pain


Research claims that significant discrepancies exist between self-report, non-verbal expressions of pain, and evidence of tissue damage, reflecting the impact of some of these criteria, in children (Doherty et al., 1993) and in adults (Craig et al., 1992). Prkachin et al. (1994) found that self-report, nonverbal expression and observers’ judgments were in agreement when the pain was severe, but that observers had difficulty judging accurately a sufferer’s inner state when the pain was submaximal, even though evidence was manifest in the face. There is no guarantee that pain expression will be detected by the observer or that the observer will be able to draw accurate conclusions about the state of the sufferer.

It has been suggested that this inconsistency reflects the multidimensional nature of pain and human ability to detect only selected features at any given time (Hadjistavropoulos & Craig, 2002). For example, it is common for clinicians to encounter patients who appear to complain unreasonably, but express minimal nonverbal pain, and the opposite. Prkachin and Craig (1995) propose that as the sufferer’s experience is expressed, there is a loss of information transfer, causing discrepancies between the different pain indices.

In this paper, we propose to understand the relationships among the various indicators of pain by recalling Wittgenstein’s reminder that the word ‘pain’ refers to ‘patterns in the weave of our life’ (Wittgenstein, 1958b), and the complexity of this weave explains why the different pain indices are not always in agreement. It also explains why third-person psychological judgments (e.g. clinical reports) are sometimes uncertain. This reflects an indeterminacy which is constitutive of our concept of pain. That indeterminacy in turn is due to communal patterns of behavior and the complex nature of our form of life: the concept of pain must be flexible and elastic because human behavior, and our reaction to it, is diverse and unpredictable (Wittgenstein, 1980b; 1982; 1992). Given the complexities of the pain experience, it cannot be expected that simple criteria could capture the full range of the experience (Hadjistavropoulos & Craig, 2002; Wittgenstein, 1980b). Hence, the indeterminacy of the pain experience and the challenges associated with characterizing emotional states logically exclude either self-report or nonverbal behavior alone as capable of giving expression to the subtleties involved.

As Wittgenstein (1958b) observes, connections between the sensation of pain and reporting pain are highly context-dependent and depend on the criteria used to judge it (e.g. self-report or observational criteria), who is expressing the self-report (e.g. age, gender), the reasons for expressing the self-report, and the person’s understanding of the consequences of reporting pain. Moreover, there is considerable potential for response bias when self-report is used to communicate features of painful experience to others (Anand & Craig, 1996). Since self-report is a fallible source of data (Schwartz, 1999), nonverbal information (e.g. facial expressions) is often needed and employed for pain assessment (Craig, 1993). Finally, even those who are closely acquainted with a person can make even the most subtle judgments with certainty, without being able to specify conclusive criteria, since their evidence is ‘imponderable’, that is, consists of a complex syndrome of behavior, context and prior events (Wittgenstein, 1958b).

Although the indeterminacy of our concept of pain means that the different pain indices are not typically connected in a rigid way, it is possible to increase sensitivity to pain communicated by facial expression by brief periods of training. Solomon et al. (1997) found that exposure to a 30-minute training video increased sensitivity to subtle facial movements associated with low levels of pain. This lends hope to the possibility of developing a clinical tool to detect pain.

Paper 4: Is there a pain face?


        Studies using the Facial Action Coding System (FACS; Ekman & Friesen, 1978) reveal a combination of facial expressions that appear to be specific to acute pain and that reveal the connection between pain facial expression and pain (Craig, 1980; Prkachin, 1992; Prkachin and Solomon, 2008). Core action units (AUs) in adults are brow lowering (corrugator: AU 4), cheek raise and lid tighten (both parts of orbicularis oculi: AU6 and 7), nose wrinkle and upper lip-raise (both parts of levator labii: AU 9 and 10), and eye closing (AU43) (Craig et al., 1992). It has been suggested that pain facial expression is a combination of the core actions along with a limited range of other actions; an expression that is better described as an indeterminate set than a fixed prototype (Prkachin & Craig, 1995). In naturalistic settings, we find it easier to describe a person as ‘in pain’ than to describe his facial features or behavior in precise physical terms, and we do not typically infer psychologically relevant descriptions of pain from austere physical ones (Wittgenstein, 1980a, 1992). For we often know the conclusions of such alleged inferences without knowing their premises (Wittgenstein, 1980a).

        Objections to the specificity of the pain face suggest that it forms part of a whole body defensive response to pain, an effort to withdraw from the stimulus and to protect the body. Salzen (2002) claims that pain facial expression consisting of tension in the facial flexor muscles, contraction of the eyes, retraction of the lips, and clenched teeth is part of a general body flexor reaction. This is based on the idea that pain facial expression is a ‘sensory-motor feeling state’, which is ‘aversive’, but separate from secondary distress due to the continuation of pain despite the initial response. Pain facial expression seems to be part of a global flexor contraction of writhing or squirming, which may spill over into the facial musculature (Frijda, 2002; Panksepp and Pasqualini, 2002). One difficulty facing this challenge is that no such whole body behaviors have been described that are specific to pain in humans or in domestic or laboratory animals (Williams, 2002).

        Moreover, given that the face is the primary target of visual attention between humans and provides a dynamic, embodied expression of pain and emotion in human interactions (Cole, 1997, 2001), some justification is required for collapsing pain facial expression into gross motor activity in connection to stimuli (Williams, 2002). Wittgenstein (1958b) makes a related point that if a person has hurt his hand, he may nurse his hand, but we comfort him: ‘…if someone has a pain in his hand, then the hand does not say so (unless it writes it) and one does not comfort the hand, but the sufferer: one looks into his face’ (Wittgenstein, 1958b, §286). It is not the body that is in pain, but the human being. Available evidence shows that the face in pain is highly salient for observers who ranked the eyes the most important feature, followed by brows, eyelids, mouth, head, forehead, and then other body parts (Prkachin et al., 1983).

        Closely related to the question of a specific pain facial expression in the individual is its detection and interpretation by observers. Judgment of pain in another person relies heavily on facial cues: brow lowering, eye blinking, cheek raise, and upper lip raise are used consistently by observers to judge pain in adults and in children (Craig et al., 1991). There is evidence of reasonably accurate identification of pain expression in adults and infants employing these facial cues (e.g., Prkachin et al. 1994).

The overlap between pain and other emotions concerning the activated facial action units, however, challenges the evidence for the detection of the pain face. After all, when people are in pain, their faces may express a blend of emotions including fear, anger, disgust, surprise, and so on, reflecting a ‘fuzzy’ emotional state of distress or discomfort, rather than expressing the specific experience of pain. It does not follow, however, that sharing of AUs across expressions renders observers unable to distinguish anger from fear or sadness. After all, detection and interpretation only have to be effective, not perfect (cf. Wittgenstein, 1958b, §79d). This may support the claim, made earlier, that the pain face expression is accurately described as an indeterminate or ‘fuzzy’ set than a fixed prototype.

Paper 5: Moebius Syndrome and pain catastrophizing


Pain intensity is strongly connected to the associated sense of danger and avoidance from physical threat (Wittgenstein, 1958b). An individual expressing pain may receive benefit when that expression is followed by protective actions by observers (Craig, 2004). However, pain expression is not merely the function of inner observation or recognition of private experiences (Wittgenstein, 1958b, 1980b, 1982). The interpersonal context may be essential in explaining how and when pain is expressed. The concept of pain is connected to pain behavior in circumstances of tissue damage or pathology (Wittgenstein, 1958b), but also involves diverse social reactions, ranging from supportive or empathic responses to interpersonal distancing and loss of relatedness, punishment, or even exploitation of vulnerability (Williams, 2002). When negative reactions to pain behavior are anticipated, suppression of pain expression might arise (Williams, 2002). In the presence of solicitous others, by contrast, one might expect robust pain expression (Morley et al., 2000).

In those in whom social support is the norm, pain catastrophizing may also occur. This is defined as ‘an exaggerated negative orientation towards actual or anticipated pain experiences’ (Sullivan et al., 1995), and can be a major determinant of the intrapersonal features of pain, including heightened pain intensity, distress and disability (Sullivan et al., 2001). It is also claimed that pain catastrophizing has interpersonal features such that those who catastrophize about pain seek social support by robust expression of pain, because of perceived danger (Sullivan et al., 2006). The presence of others may then function as a discriminative cue for the expression of pain in those who catastrophize about pain.

How social presence affects pain behavior in adults with congenital facial paralysis is unknown. In this paper we report the experiences of social presence on pain expression in adults with Möbius syndrome, and the extent to which it is moderated by any tendency to catastrophize about pain. Due to the various features associated with Möbius syndrome, including facial immobility, interactions with other people can be difficult to achieve and sustain (Briegel, 2006). They are at higher risk of experiencing rejection or lack of reinforcement, especially with unknown others. These experiences can lead to low self-esteem, behavioral problems (e.g., episodic dyscontrol) and even psychiatric disorders (Cole, 1997, 1999, 2001).

In addition to these potential problems with communication of pain, there is also evidence that some with Möbius have altered or reduced emotional experience (Cole and Spalding, 2008). This might also modify their expression of negative experiences like pain. Given these overlapping problems, expression, experience and relatedness to others, we investigated the effects of social presence, emotional experience and pain experience and expression in those with Möbius. This is a rare syndrome and we felt that the best way to approach this initially was through extended narrative, though we have also used well known inventories of emotional experience and pain.

We expected that it may be likely that adults with Möbius would show more pain behavior in the presence of a significant other than in the presence of a stranger, and that this would be most pronounced in adults who frequently catastrophize or exaggerate the threat value of pain sensations. 

Please note: This proposal requires ethical approval.



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