Background: People often state that they are "sensitive" or "insensitive" to pain. However, the accuracy and clinical relevance of such statements is unclear.
Objective: The aim of this study was to search for associations between self-perception of sensitivity to pain and experimental pain measures, including known psychophysical inhibitory or excitatory pain paradigms.
Subjects and methods: Subjective sensitivity to pain was reported by 75 healthy participants and included three self-perceived variables: pain threshold, pain sensitivity and pain intensity in response to a hypothetical painful event (hypothetical pain intensity [HPI]). Experimental pain measures consisted of thermal pain threshold (°C), suprathreshold thermal pain intensity (Visual Analog Scale, 0-100) and the psychophysical paradigms of conditioned pain modulation (CPM) and temporal summation (TS), representing inhibitory and excitatory pain processes, respectively.
Results: No significant correlations were found between self-perceived pain threshold or pain sensitivity and any of the experimental pain measures. In contrast, the reported HPI correlated with thermal pain threshold (r = -0.282; p = 0.014), suprathreshold thermal pain intensity (r = 0.367; p = 0.001) and CPM (r = 0.233; p = 0.044), but not with TS.
Conclusion: Self-perception of pain sensitivity articulated by intangible expressions such as pain threshold or pain sensitivity is unrelated to actual sensitivity to experimental pain. In contrast, when measured by intensity of a hypothetical painful event (HPI), sensitivity to pain is associated with some, but not all, experimental pain reports. Further studies are needed for better understanding of these associations and their potential clinical significance.
Keywords: CPM; QST; TS; conditioned pain modulation; pain intensity; pain threshold; quantitative sensory testing; temporal summation.