Identifying pain perceptual biases related to fear of pain and threat in a pain-free sample.

Abstract

The association between fear of pain (FOP) and pain intensity has remained unclear. This study aimed to examine whether highly pain-fearful participants showed pain perceptual biases to general painful stimulus or to specific threatening painful stimulus. Fifty-nine undergraduates were recruited into low (n=30) and high (n=29) FOP groups and completed a threatening pain perception task with two tasks. Task 1 assessed pain perceptual biases by calculating the percentage of near-threshold pain stimulus judged as painful and assessing the average pain intensity ratings to those painful stimuli. Task 2 assessed pain perceptual biases by measuring pain ratings to each single threshold (low intensity) and twice-threshold (high intensity) pain stimulus. Results from task 1 indicated that higher FOP levels were associated with higher pain sensitivity when pain was appraised as a threat, reflected as high FOP group reporting higher pain intensity to those stimuli judged as painful in high threat condition than in low threat condition. Consistently, results from task 2 observed that when noxious stimulus intensity increased to threshold pain and twice threshold pain levels, high FOP group also generally reported higher pain intensity in high threat condition than in low threat condition. However, for both tasks, no such threat level differences were observed in low FOP group. The current research emphasized that participants with higher FOP level showed pain perceptual biases to specific threatening painful stimulus. Threat appraisal of pain played a key role in the positive association between pain-related fear and pain perceptual biases. The findings highlight the modulatory influence of threat appraisal of pain in the positive association between pain-related fear and pain perceptual biases.