THE EFFECTS OF IMAGERY AND SENSORY DETECTION DISTRACTORS ON DIFFERENTMEASURES OF PAIN - HOW DOES DISTRACTION WORK

Objectives. Two experiments compared the effects of different distract ion tasks on pain. Based on multiple-resource theory, Expt 1 predicted that the more a distracter shares processing resources with pain perc eption the greater the interference between the two. Experiment 2 test ed whether the emotional content of the distracter would differentiall y effect measures that are supposedly reflective of the affective comp onent of pain. Design. Both experiments used repeated measures designs , with counterbalanced distraction conditions. Methods. In Expt 1 20 p articipants indicated their pain threshold. No instructions, or one of three distraction conditions were presented across four blocks of pot assium iontophoresis. The distracters were: thermal and light detectio n, and neutral imagining. In Expt 2 30 participants had three blocks o f pain threshold, pain tolerance, and pain rating trials. For threshol d, tolerance, and rating trials, one block was without distraction, a second block was completed during light detection, and a third block w hile imagining an enjoyable holiday. Results. In Expt 1 all the distra cters increased pain threshold. The two detection tasks were similarly effective, and more so than the imagination task. Performance on the two detection tasks was impaired by painful stimulation similarly for both tasks. In Expt 2 the visual detection distracter increased pain t hreshold and tolerance and reduced pain ratings while pleasant imagery only increased pain threshold. Conclusions. These results indicate th at a task that requires attention to external cues has more impact on pain than either a positive or neutral imagination task. However, it i s not clear that the specific resources used by the distraction tasks moderated pain differentially as predicted by multiple-resource theory .