The dynamics of pain and affect: Toward a salient phenotype for chronic pain

For decades, clinical evidence has suggested that the subjective experiences of pain and emotion are intertwined. More recently, neuroimaging data have supported this notion, implicating both cortical and subcortical brain regions in overlapping regulatory roles for pain and emotion. There is a need presently to focus research efforts on the identification of salient phenotypes that more fully explicate the relation of pain and emotion, specifically in the context of chronic pain. This can be accomplished through the identification of endogenous brain mechanisms that can be translated into clinically relevant markers of vulnerability and resilience, and through the description of naturalistic processes that promote or inhibit adaptation to chronic pain. The present chapter focuses on how variability in the dynamics of the affect system and its covariation with pain processes influence both brain function and daily experience with chronic pain. Specifically, the chapter addresses the roles of both positive and negative affects during states of heightened pain and provides a rationale for why characterization of affective reactivity to pain at the levels of brain function and daily process is essential to the evolution of more highly targeted treatment strategies.