Several of you in the audience have suggested that the message implicit in our initiative is too critical, especially of the laboratory animal personnel who are on the front line of laboratory animal care and welfare. We cannot escape the fact that the initiative does criticize what is currently being done, and I am not going to try to sugarcoat the issue.

However, I want to state very strongly that such criticism is not directed at people's motives or character. We recognize that there is an enormous amount of concern for animals in laboratories. Pain and distress is something that concerns all of us whether it is experienced by humans or animals. A concern for other beings' suffering is a fundamental element of any humane, empathic, individual.

What we think is the main issue is that we disagree on definitions and on the interpretation of what few empirical data are currently available to guide us in deciding what causes animal distress. That is where I see the disagreement, and if there are friction and unhappiness with the HSUS pain and distress initiative, we would like to see the debate focus on how we differ as regards definitions and the like.


People commonly use pain, distress, and suffering as synonyms. I want to argue very strongly that these words do not refer to the same states. There are overlaps but they are absolutely not synonyms. There are other terms as well that describe parts of responses involved in suffering.

Twenty years ago, nociception was described to me as a scientific euphemism for pain. However, I now know that this is not a scientific euphemism at all. It is a very precise term that is not equivalent to the sensation of pain at all. It simply refers to the “stimuli ” passing from the nociceptors up through the nerve fibers that conduct those stimuli. The sensation of pain may or may not be an outcome of such nociception. In fact, what may be viewed as behavior signaling pain may simply be a nociceptive reflex.

One example that illustrates this concept is the experience of a human being with a high spinal cord break. Such an individual could still have the nociceptive reflex loop for the lower limbs and will withdraw his or her foot from a hot iron or a painful stimulus, but there will be no pain perception because the central nervous system is not involved. The behavior is the result of a nociceptive reflex.

With regard to pain, the HSUS is not greatly concerned about pain research in the context of our pain and distress initiative. By and large, the International Association for the Study of Pain (IASP) has established good guidelines for ensuring that pain research protocols minimize pain. In quite a bit of acute pain research, the animal controls the level of intensity of the stimulus, and the animal says, “This is too much; I am going to stop now.” In a sense, the animal is a

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