Abstract
A scientific understanding of pain requires an experiential‐phenomenological approach and method, one that precedes mechanistic explanations provided by neuroscience, molecular neurobiology, and even the rest of psychology. A key challenge in this approach is to find ways to observe and characterize the experience of pain. An experiential method applied to both clinical and experimental pain has found three common factors in all instances of pain: a somatic or visceral experience that is comprised of 1) unique sensory qualities that are like those which occur during tissue damaging stimulation, 2) a closely related meaning of intrusion and/or threat, and 3) a feeling of unpleasantness and/or other possible negative emotion(s) in response to 1 and 2. These three factors comprise an experiential definition of pain and they are each correlated with brain activities and functional connections that serve them. Much more is to be learned about the factors and their neural basis.