Increasingly, patients are being told that their pain is in their brain. We have no doubt that such messages are delivered by well intentioned clinicians, who are rightly dissatisfied with outdated concepts of the biology of pain. Such dissatisfaction certainly lends itself to ready acceptance of new paradigms, however implausible they may be — fancy proposing that one’s pain is in one’s head when it is clearly in one’s back! It is a fine line, though, between embracing the critical role of brain-held mechanisms in producing pain and presuming that it is in these mechanisms where the pain itself resides.
Our perspective is that pain is emergent. Emergent properties are those that are possessed by entire systems. A system comprises several distinct parts, and these parts interact with one another to give the system its emergent properties. There are two ruling criteria of emergence: that the one system, comprising the same components, can produce a range of emergent properties; and that none of the individual units comprising the system are capable in themselves of producing any of the emergent properties. The temptation is to simplify things a little and state that pain is an emergent property of the brain. Indeed, either or both of us have fallen into this oversimplification in our writing at some stage. However, on what grounds do we confine the system to the brain? A more accurate position is that pain is an emergent property of the person who is suffering it. There is a compelling body of research that clearly challenges a “neurocentric” view of pain and, in so doing, allows the propagation of new conceptual models with which to investigate conditions such as complex regional pain syndrome.