Attentional bias towards pain-related information in chronic pain; a meta-analysis of visual-probe investigations

Research investigating the presence of attentional bias in chronic pain has produced mixed results. The purpose of this review is to summarise former research using the visual-probe task to explore attentional bias in pain populations, and meta-analyse the results of controlled investigations comparing individuals with chronic pain to healthy controls. Ten eligible studies were included in this analysis (chronic pain n = 515, control n = 314). Overall, individuals with chronic pain were found to show significantly greater bias towards pain-related information compared to controls, with an effect size of .36 (Hedges' adjusted g). The time-course of attentional bias was also explored, with evidence found for significant bias during stages of initial orienting of attention (effect size .29) and maintained attention (effect size .42). Bias therefore appears more pronounced during later stages of attention, possibly arising from processes of rumination. It is important for future research to fully explore the role attentional bias plays in the causation and maintenance of chronic pain, and the potential consequences bias may have upon quality of life. (C) 2011 Elsevier Ltd. All rights reserved.