Figure 5.
An Illustration of the Levels of Inquiry in Pain Behavior That Imaging Has the Possibility to Inform Upon.
The Fear-Avoidance Model is an adaptation from Vlaeyen et al. and Lethem et al.69,70 Notably, inflammatory processes may interact at several levels of the pain behavior circuit. For example, the catechol-O-methyltransferase (COMT) val158met polymorphism may influence the neuronal71 and opioidergic72 response to pain (but see also Nicholl et al.73). Furthermore, the 18-kDa translocator protein (TSPO) Ala147Thr genotype asserts a strong influence on the binding affinity of microglial PET tracers74 and thus needs to be accounted for in between subject analyses. At the other end of the spectrum, imaging studies are beginning to explore how culture may interact with brain processing of perception and emotional valuation.75