Abstract
Social interactions affect individual behaviours, preferences, and attitudes. This is also critical in the context of experiencing pain and expressing pain behaviours, and may relate to learned emotional responses. In this respect, individual variability in the medial prefrontal cortex (mPFC), which is involved in adjusting an organism's behaviour to its environment by evaluating and interpreting information within the context of past experiences, is important. It is critical for selecting suitable behavioural responses within a social environment and may reinforce maladaptation in chronic pain. In our study, we used brain imaging during appetitive and aversive pavlovian conditioning in persons with chronic back pain (CBP), subacute back pain (SABP), and healthy controls (HC), together with information on spouse responses to pain behaviours. We also examined the relationship of these responses with pain-related interference in the patients. Our findings yielded a significant negative association between mPFC responses to appetitive and aversive learning in CBP. We also observed a significant negative association for mPFC responses during aversive learning and distracting spouse responses, and a significant positive association between mPFC responses during appetitive learning and solicitous spouse responses in CBP. Both significantly predicted pain-related interference in the CBP group (explained variance up to 53%). Significant associations were not found for SABP or HC. Our findings support an association between appetitive and aversive pavlovian learning, related brain circuits and spouse responses to pain in CBP, where appetitive and aversive learning processes seem to be differentially involved. This can inform prevention and early intervention in a mechanistic approach.