The determinants of pain revisited: Coordinates in sensory space

Abstract

Ron Melzack recognized that the gate control hypothesis of 1965 was incomplete. This led to the publication of a book chapter that would someday be referred to by some as 'the classical view' of pain mechanisms. However, this paper presented some conceptual problems for research on pain mechanisms by using the term 'motivational-affective' to define a determinant of pain. To facilitate research and eventually improve practice, the determinants of pain need to be identified and quantified more clearly. In the present article, three critical dimensions of sensory experience that define pain and related sensory experiences are identified: sensory salience, affect and motivational dominance. The authors show that each of these dimensions can be measured and are mediated by specific neurophysiological mechanisms. Pain and other somatic sensations emerge from the conjoint actions of these neurophysiological systems and fall within unambiguously defined coordinates of the three-dimensional sensory surface that they form. Pain mechanisms would be better understood if research focused on the physiology and psychology of these fundamental sensory dimensions and included a wider range of sensory systems.