Identifying experimental methods to determine the effect of pain on attention: a review of pain, caffeine, alcohol and nicotine studies.

Objectives: To review published studies of the effects that pain and common psychopharmacological substances have on the attentional performance of healthy adults. To identify which attentional tasks have the greatest potential to investigate the effect of pain on attention and provide recommendations for future research.

Methods: A search was conducted for reports of experimental studies of attention in the context of pain. This was supplemented with studies on attention and caffeine, nicotine and alcohol. Studies were included if they used a healthy adult sample, used experimental or quasi-experimental methods, were relevant to the study of attention or interruption of pain and/or examined the acute effects of a substance on attention.

Results: Thirty-two papers, with 49 different experimental studies were identified (12 pain, 21 nicotine, 7 caffeine, 9 alcohol). Fourteen different tasks were reviewed across six domains of attention. The most promising measures of attention were the continuous performance task, flanker task, endogenous pre-cuing task, n-back task, inhibition task and dual task.

Conclusions: There are reliable tasks that could be used to determine the effects of pain on attention. Future research is required that develops the utility of these tasks to improve our understanding of the effects pain and analgesia have on attentional performance.