P: Why the interest in facial expression?
S: Well, the face is for human interactions a rich source of information: one can often appreciate features of another person’s emotions, motives, thoughts, attention, and intentions by scanning his or her face.
P: I think my spouse’s face is a work of fiction.
S: At least fiction is more interesting than autobiography.
S: Imagine being unable to monitor and correctly interpret the ongoing patterns of your spouse’s facial activity. You would be vulnerable to serious social deficits.
P: Like divorce?
S: Not exactly. Consider Möebius Syndrome, a congenital condition of facial paralysis. These individuals often have great difficulty detecting and monitoring in others inner states on the face. As a result, they tend to experience rejection and lack of reinforcement from others, and may become withdrawn and highly introspective.
P: The plasticity of the face must make it very difficult for them.
S: Facial expression matters. There tends to be added value even when others are communicating verbally, as the information conveyed by the face is unlikely to be entirely redundant with the content of speech.
P: I see where your interest in pain comes in now. Facial expression may prove useful when attending to others who have been hurt, or another person’s facial grimaces may signal danger and allow one to avoid looming personal threat.
S: There is a general tendency to situate oneself so as to be able to attend to facial activity.
P: Just think of mothers who become utterly absorbed in their babies’ facial expressions!
S: That’s a great illustration. And, infants are equally attentive to their caretakers’ facial expressions. The capacity to attend to and use facial activity persists throughout life.
P: The child learns facial expressions in attending to and interacting with a caregiver.
S: Children are acculturated to social standards and normative patterns consistent with the social environments in which they grow up.
P: This means that behavior – including facial displays – conforms to cultural expectations.
S: Through observation, instruction and reinforcement, children learn facial displays that follow familial and social rules.
P: Fine. I think this is fairly uncontroversial, however. I mean, what determines the link between subjective states and overt behavior? Do first relationships connect mind and behavior?
S: That’s a fundamental question. Consider the response of very young infants to tissue damage. The reactions are relatively global – involve the whole body – and are reflexive in nature. Various studies report that the reactions of infants to pain are shaped and transformed during development into socially responsive patterns of behavior. Facial expressions of pain develop as part of this transformation.
P: That is an interesting observation, but uncontroversial. And, you haven’t addressed my question. You seem to be suggesting that the possibility of pain is conditioned by the possibility of its expression. I mean, isn’t the pain given – whether it can be expressed and how it is expressed seem to be further matters.
S: I am not certain it is quite so simple to divide facial displays neatly into inner and outer aspects. Isn’t pain given in expressive displays? Facial expression makes pain visible to others, and also for the patient. Facial activity may also contribute to the experience of pain.
P: I am not convinced.
S: Well, I am speculating that modulation of facial expression may alter the pain-sensation. The vigor of the facial display influences the magnitude of the subjective experience.
P: Oh, you mean: ‘grin and bear it’, and all that?
S: Right: ‘keep a stiff upper lip’. It is relatively easy to acknowledge this point, at least intuitively.
P: I can see benefits here: attenuated facial expression of pain decreases subjective distress, and increases pain tolerance.
S: Research on individuals with Möebius Syndrome reveals that they have high pain tolerance and decreased distress in pain because they cannot make facial expressions.
P: Or, more precisely: ‘…because they cannot experience facial feedback’.
S: So, here is an idea: feedback from the face may permit subjective differentiation of inner states.
P: This idea may have the following negative consequence, however: if attenuated facial expression of pain decreases inner distress in the individual, is detection of pain in others thereby weakened? Does perception need a face?
S: Studies on adults with Möebius Syndrome show that they have no impairment in emotional facial expression recognition. This means that the ability to produce facial expressions is not a necessary prerequisite of their recognition.
P: It follows that the inability to experience facial feedback in oneself does not inhibit facial recognition of emotion in others. I guess the same point applies to perception of pain.
S: I believe so. We can illustrate this point further. Are you familiar with CIP?
P: What is it?
S: CIP: congenital insensitivity to pain. It is characterized by dramatic impairment of pain perception since birth. Painless events include wounds, burns, bone fractures, deliveries, and so on. There are some residual pain experiences like headaches and low back pain in these individuals, however.
What is noteworthy is that these people can perceive pain in others despite their own congenital insensitivity to pain.
P: An experience of pain is not required for perceiving pain in others.
S: We might put it like this: to perceive pain in others, we do not need a pain, nor even a face, but the concept of pain.
P: We do not feel the sensory aspects of another’s pain, but we may resonate with the agony of a person in pain when we encounter facial expression.
S: The degree to which we ‘share’ another’s agony depends on empathy.
P: Does empathy need a face?