The role of the behavioural approach and inhibition systems (BAS/BIS) in the psychological adaptation to chronic pain

Abstract

Reinforcement Sensitivity Theory proposes a neuropsychological model that attempts to explain how people respond to stimuli, including pain stimuli. The theory suggests that differences in sensitivity to reward or punishment, which could entail different forms of behaviour, may be the basis of individual differences in personality. The activity of two brain systems with differentiated neurobiological substrates may underlie these differences: the Behavioural Inhibition System (BIS) and the Behavioural Approach System (BAS). BIS is activated by punishment-related or intense stimuli and has been associated with anxiety or negative moods. BAS is activated by reward-related stimuli and has been associated with emotions such as pleasure, hope, or relief. Both systems have been proposed as relevant to the development of mental disorders in which anxiety plays a central role. Given the criticism received by the Fear-Avoidance Model of Pain, it has recently been postulated that BIS and BAS could explain differences in the psychological experience and adaptation of people with chronic pain pathology. The initial empirical evidence available has shown that the level of activation of these systems may contribute to explaining the factors underlying the cognitive, emotional, behavioural, and motivational processes present in individuals with chronic pain, and thus the defining factors of psychological adjustment to this pathology. The analysis of the role of these systems in the psychological experience of chronic pain may open future lines of research, deepen our understanding of the issues, and guide recommendations on the choice of psychological treatment for people with chronic pain. The objective of this study was to present the theory and the most relevant findings on BIS and BAS and pain.