Distraction from pain: The role of selective attention and pain catastrophizing

Abstract

Background: Previous research has demonstrated the efficacy of cognitive engagement in reducing concurrent pain. However, little is known about the role of individual differences in inhibitory control abilities and negative pain-related cognitions in modulating the magnitude of this type of distraction from pain.

Methods: In a pain distraction paradigm, 41 participants completed a working memory task with both a demanding high load condition (2-back) and an easy low load condition (0-back), while receiving warm or painful thermal stimuli to their left forearm. To control for individual differences in sensitivity to pain and perceived task difficulty, nociceptive stimulus intensity and task speed were individually calibrated. Additionally, participants completed a set of cognitive inhibition tasks (flanker, go/nogo, Stroop) and questionnaires about negative pain-related cognitions (fear of pain, pain catastrophizing) prior to the distraction paradigm.

Results: As expected, engaging in the high load condition significantly reduced perceived intensity and unpleasantness of nociceptive stimuli, compared to the low load condition. The size of the distraction effect correlated significantly with better cognitive inhibition and selective attention abilities, as measured by the flanker task. A moderation analysis revealed a significant interaction between pain catastrophizing and performance in the flanker task in predicting the distraction effect size: Participants who performed well on the flanker task showed more pain reduction, but only when they were average to high pain catastrophizers.

Conclusions: Selective attention abilities and pain catastrophizing seem to be important factors in explaining individual differences in the size of the analgesic response to a distractive task.

Significance: Understanding which factors influence the effectiveness of cognitive engagement in distracting from pain could help to optimize its therapeutic application in patient care. This study shows that a complex interplay of cognitive inhibition abilities, specifically selective attention, and negative pain-related cognitions, such as pain catastrophizing, modulate the magnitude of the distraction effect.

FIGURE 1

(a) Mean intensity ratings for the four different conditions. Bonferroni corrected paired sample t‐tests revealed that intensity ratings for painful, but not warm, stimuli differed significantly per task condition (distraction vs. control). (b) Mean unpleasantness ratings for the four different conditions. Bonferroni corrected paired sample t‐tests revealed that unpleasantness ratings for painful, but not warm, stimuli differed significantly per task condition (low vs. high load). Error bars reflect ± SD. Note that warm stimuli were significantly less intense and unpleasant than painful stimuli, irrespective of task difficulty, p < 0.001. For simplification, these differences are not marked as significant in the figure. ***p < 0.001

FIGURE 2

Pain catastrophizing moderated the relationship between the flanker effect (a smaller effect is assumed to reflect better selective attention abilities) and the size of the distraction effect on the intensity rating scale. Better selective attention abilities were associated with a significantly larger distraction effect, but only if participants scored high on the PCS. Note that the here depicted division of PCS scores into low, medium and high is just for illustration purposes, and that PCS scores were treated as a continuous variable in the moderation analysis