In addition to the five senses, nineteenth-century German academics believed in Gemeingefühl: a slate of perceivable bodily states “in the most diffuse and general sense”—fluctuating temperatures, rushing blood, lurching organs, hunger, thirst, breathlessness, and physical pressures like pain, itching, and tickling.
These academics explained the mystery of chronic “pain without lesion” as a disorder of Gemeingefühl—an inability to correctly perceive internal sensations. When, in the mid-1970s, the McGill University psychologist Ron Melzack began developing a modern pain assessment still widely used today, he believed that language could ferry pain from this unknowable “borderland between soma and psyche” into the realm of treatable medicine.
After collecting 102 words used by patients at a pain clinic to describe their various agonies, Melzack set out to find a framework within this list that could not only quantify the physical intensity of a person’s hurt but also assess their experience of it. “It gradually dawned on me that the words could serve as a questionnaire that would provide credible evidence of the perceived, subjective qualities of a person’s pain,” he later recalled, “and perhaps throw light on what parts of the brain were involved in producing such feelings.”
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Melzack’s invention, the McGill Pain Questionnaire, or MPQ, asked patients to describe their pain using words that fell into three categories: the sensory, the affective, and the evaluative. The sensory category identifies pain’s physicality through qualities such as temperature, intensity, and magnitude. (As virtually everyone knows, pain can prickle, or shoot, or ache, or sting—and each of these sensations can be unlike any of the others.)
Words within the second, affective category capture pain’s emotional impact—whether it exhausts or sickens, terrifies or tortures. The third, final, and most narrow evaluative category assesses the overall episode: Was it annoying, miserable, intense, unbearable?
Within this vocabulary, language can provide “an external image of interior events,” as the essayist Scarry put it. Questionnaires like the MPQ also elevated pain from a handful of physical symptoms to an experience nested in emotion, environment, and expectation. “Pain is not one thing. There’s pain, and there’s the suffering of pain,” says Nancy Berlinger, a researcher at the Hastings Center, a nonprofit bioethics institute. “What you’re feeling, and how you feel about it.”
Sadly, Alzheimer’s irreversibly robs a person of the cognition required to make this conception of pain medically useful. As the disease advances, a person loses the ability to create new memories, use language, control emotions, and critically perceive, analyze, or convey the world around and inside them.