Department of Surgery, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
J Neurophysiol. 2012 Oct;108(8):2276-81. doi: 10.1152/jn.00391.2012. Epub 2012 Aug 1.
High-frequency conditioning electrical stimulation (HFS) of human skin induces an increased pain sensitivity to mechanical stimuli in the surrounding nonconditioned skin. The aim of this study was to investigate the effect of HFS on reported pain sensitivity to single electrical stimuli applied within the area of conditioning stimulation. We also investigated the central nervous system responsiveness to these electrical stimuli by measuring event-related potentials (ERPs). Single electrical test stimuli were applied in the conditioned area before and 30 min after HFS. During electrical test stimulation, the reported pain intensity (numerical rating scale) and EEG (ERPs) were measured. Thirty minutes after conditioning stimulation, we observed a decrease of reported pain intensity at both the conditioned and control (opposite arm) skin site in response to the single electrical test stimuli. In contrast, we observed enhanced ERP amplitudes after HFS at the conditioned skin site, compared with control site, in response to the single electrical test stimuli. Recently, it has been proposed that ERPs, at least partly, reflect a saliency detection system. Therefore, the enhanced ERPs might reflect enhanced saliency to potentially threatening stimuli.
高频电刺激（HFS）作用于人体皮肤会引起周围非刺激区域对机械刺激的痛觉敏感性增加。本研究旨在探讨 HFS 对作用于刺激区域内的单个电刺激所引起的痛觉敏感的影响。我们还通过测量事件相关电位（ERP）来研究中枢神经系统对这些电刺激的反应。在 HFS 之前和之后 30 分钟，在条件化区域应用单个电测试刺激。在电测试刺激期间，测量报告的疼痛强度（数字评分量表）和 EEG（ERP）。在条件化刺激后 30 分钟，我们观察到对单个电测试刺激的条件化和对照（对侧手臂）皮肤部位的报告疼痛强度均降低。相比之下，与对照部位相比，我们观察到在条件化皮肤部位对单个电测试刺激的 ERP 幅度增强。最近，有人提出，ERP 在一定程度上反映了一种突显检测系统。因此，增强的 ERP 可能反映了对潜在威胁刺激的更高突显度。
