Department of Experimental-Clinical and Health Psychology, Ghent University, Ghent, Belgium.
Department of Experimental Psychology, Ghent University, Ghent, Belgium; Research Foundation - Flanders (FWO), Brussels, Belgium.
Brain Res. 2019 Nov 15;1723:146383. doi: 10.1016/j.brainres.2019.146383. Epub 2019 Aug 13.
The present study investigated if preparing a movement that is expected to evoke pain results in hesitation to initiate the movement (i.e., avoidance) and, especially, if the allocation of attention to the threatened body part mediates such effect. To this end, healthy volunteers (N = 33) performed a postural perturbation task recruiting lower back muscles. In 'threat trials', the movement was sometimes followed by an experimental pain stimulus on the back, whereas in 'no-threat trials', a non-painful control stimulus was applied. Electroencephalography (EEG) was used to assess attending to the lower back. Specifically, somatosensory evoked potentials (SEPs) to task-irrelevant tactile stimuli administered to the lower back were recorded during movement preparation. Reaction times (RTs) were recorded to assess movement initiation. The results revealed faster responses and enhanced somatosensory attending to the lower back on threat trials than on no-threat trials. Importantly, the amplitude of the N95 SEP component predicted RTs and was found to partially mediate the effect of pain anticipation on movement initiation. These findings suggest that somatosensory attending might be a potential mechanism by which pain anticipation can modulate motor execution.
本研究旨在探讨预期会引起疼痛的运动准备是否会导致对运动的犹豫（即回避），特别是注意力分配到受威胁的身体部位是否会影响这种效应。为此，健康志愿者（N=33）进行了一项姿势扰动任务，募集了下背部肌肉。在“威胁试验”中，运动有时会在背部引发实验性疼痛刺激，而在“无威胁试验”中，会施加非疼痛控制刺激。脑电图（EEG）用于评估对下背部的注意力。具体来说，在运动准备期间记录了对下背部给予的与任务无关的触觉刺激的体感诱发电位（SEP）。记录反应时间（RT）以评估运动起始。结果表明，与无威胁试验相比，威胁试验中对下背部的反应更快，体感注意力增强。重要的是，N95 SEP 成分的振幅预测了 RTs，并发现其部分介导了疼痛预期对运动起始的影响。这些发现表明，体感注意力可能是疼痛预期调节运动执行的潜在机制。
