Does Brief Cognitive Behavioural Intervention Impact Perception of Thermal Pain? An Investigation of Sensory, Emotional, and Cognitive Factors

Abstract

Salomons and colleagues (2014) demonstrated that brief cognitive-behavioural therapy can significantly reduce secondary hyperalgesia (SH) and pain unpleasantness (PU) in healthy participants. Reductions in SH were also associated with reduced pain catastrophizing, suggesting changes in central sensitization are related to changes in pain cognitions. However, more research is needed to understand emotional and cognitive factors influencing pain perception. This thesis investigates relationships between sensory, emotional, and cognitive factors of thermally induced pain in healthy individuals. An overview of pain theories, from early biological models to contemporary biopsychosocial frameworks, is provided. The importance of putative psychological factors in pain perception – anxiety, depression, pain catastrophizing, and mindfulness – is explained. To replicate and extend the work of Salomons et al. (2014) and further examine the role of these factors in pain perception, a randomized control trial was conducted. Participants underwent multiple sessions of thermal pain induction over several weeks, with participants randomly assigned to receive either brief pain-focused cognitive-behavioural or brief non-pain-focused interventions. Measures of psychological factors were taken at baseline and measures of SH, pain intensity (PI), and PU were measured at various points over the course of the trial. Key findings were that both the pain-focused CBT and non-pain-focused intervention reduced SH. Similarly, PI and pain PU reduced in both groups over time; however, it is unclear whether this was due to both interventions having an effect or simply habituation. Notably, baseline measures of anxiety, depression, pain catastrophizing, and mindfulness did not moderate outcomes for PU in participants receiving pain-focused cognitive-behavioural intervention, suggesting the effectiveness of cognitive interventions may operate independently of initial psychological profiles. Given that both groups demonstrated similar reductions in pain outcomes over time, and that there was no no-intervention control group, the observed changes may reflect factors unrelated to the interventions, such as effectiveness of both interventions, habituation, or regression to the mean. The findings highlight the need for further investigation into factors through which cognitive-behavioural interventions influence pain perception. Elucidating factors underlying the effects of psychological interventions on pain perception may ultimately serve to enhance treatment options and outcomes for both acute and chronic pain management.