The behavioral inhibition and activation systems and function in patients with chronic pain

Background: The behavioral inhibition system (BIS) and behavioral activation system (BAS) are two neuropsychological systems hypothesized to underlie response to cues signaling potential reward and punishment, respectively, also in patient responses to chronic pain. Objectives: The aim of this study was to test these hypotheses by evaluating the relative contributions of BIS and BAS to the prediction of function in sample individuals with chronic musculoskeletal pain. Methods: 253 participants were administered a battery of questionnaires. Two linear regression analyses were performed to evaluate the contributions of BIS and BAS to the prediction of impairment and psychological function, and to determine if either or both moderated the effects of pain intensity on function. Results: After controlling for demographic factors, pain diagnosis, and characteristic pain intensity, BIS contributed significantly and independently to the prediction of pain-related physical impairment and psychological function. BAS activity had a significant and direct effect on psychological function only. No moderating effects of BIS or BAS on the association between pain intensity and function were identified. Discussion: The findings are generally consistent with a BIS-BAS 2-factor model of chronic pain, suggesting BIS and BAS activity as potential targets for chronic pain treatment.