There were no child welfare inspectors to be seen, no one around concerned about my experiments in maturation, and no one, including my father, seemed to notice or to care, except my father called me a sissy and told me to stay put and keep quiet. I did. I survived, shaking. But like the residents of Vicksburg, Mississippi, I still have limbic, neuroendocrine, and autonomic reactions on the fourth of July, when we both lost a battle.
Remembering my emotions and pain that night in the late 1940s, I recently asked my neurologist colleague whether the nociceptive anatomy of rodents and rabbits resembled mine. His initial answer was rapid, emphatic, and intuitive: “I believe placental mammals, despite some differences, due to modifiers of the responses, are very similar. ” Period. I learned also from three decades of books and articles that primate nociceptors, A-delta and C sensory fibers, spinal tracts, brain tracts, the limbic system, thalamus, somatosensory cortex, and brain/weight ratio seemed to be very, very similar to those in rats, even more alike than between those beloved cats and us human primates. I was comforted also to learn that most aversive or avoidance behaviors required no isocortex; my prereptilian brain parts could protect or harm me, rodents, and rabbits alike, quite well on its own, without much isocortical or frontal lobe override.
Then, recently, I wanted to know why my father had missed my obvious signs. After all, he had been a kid once. I wanted to know whether proxy assessment by humans of distress and pain in other talking humans, human infants, and in placental mammals was valid, reliable, and sensitive.
Lynne Holton and colleagues (1995, p. 64) of Glasgow and Edinburgh described in JAVMA that “currently, there are no effective objective methods of measuring the intensity of clinical pain.” No mention of distress. Dr. Horton continued to state that one must rely on subjective assessments that must be valid, reliable, and sensitive. She favored having trained teams use a numeric scale for pain evaluation, but that scheme had deficiencies also. Francis J. Keefe and others (1991) at Duke and elsewhere published in ILAR News that well-trained observers using an observation scale with talking children found high correlations between the two groups' interpretations of the test group's behaviors to stressors. I would hope so. Franklin D. McMillan (2000) stated in JAVMA that “Numerous studies provide evidence to suggest that proxy responses by parents correlate poorly with the perceptions of the child they are representing—especially on certain subjective feelings regarding illness and emotional states ” (p. 1908). He believes there is no valid, current instrument for measuring QOL in animals. He advocates assembly of a diverse population of experts to establish measuring instruments and conduct research on their use in animal studies. So do I.
Yet, despite these questions of variability among individuals and groups in linking overt behaviors with degrees of distress and pain, several excellent sources, including those published by J. Wallace Fiat (Convenor and others) in 1990 in Laboratory Animals; in Recognition and Alleviation of Pain and Distress in Laboratory Animals (NRC 1992); and in Carstens and Moberg's (2000)