Neuro-MI, Milan Center for Neuroscience, Dept. of Psychology, University of Milano-Bicocca, Italy.
Neuro-MI, Milan Center for Neuroscience, Dept. of Psychology, University of Milano-Bicocca, Italy.
Brain Res. 2020 Apr 15;1733:146712. doi: 10.1016/j.brainres.2020.146712. Epub 2020 Feb 7.
The present electrophysiological (EEG) study investigated the neural correlates of perceiving effortful vs. effortless movements belonging to a specific repertoire (ballet). Previous evidence has shown an increased heart and respiratory rate during the observation and imagination of human actions that require a great muscular effort. In addition, TMS (transcranial magnetic stimulation) and EEG studies have evidenced a greater muscle-specific cortical excitability and an increase in late event-related potentials during the observation of effortful actions. In this investigation, fifteen professional female ballet dancers and 15 controls with no experience whatsoever with dance, gymnastics, or martial arts were recruited. They were shown 326 short videos displaying a male dancer performing standard ballet steps that could be either effortful or relatively effortless. Participants were instructed to observe each clip and imagine themselves physically executing the same movement. Importantly, they were blinded to the stimuli properties. The observation of effortful compared with effortless movements resulted in a larger P300 over frontal sites in dancers only, likely because of their visuomotor expertise with the specific steps. Moreover, an enhanced Late Positivity was identified over posterior sites in response to effortful stimuli in both groups, possibly reflecting the processing of larger quantities of visual kinematic information. The source reconstruction swLORETA performed on the Late Positivity component showed greater engagement of frontoparietal regions in dancers, while task-related frontal and occipitotemporal visual regions were more active in controls. It, therefore, appears that, in dancers, effort information was encoded in a more refined manner during action observation and in the absence of explicit instruction. Acquired motor knowledge seems to result in visuomotor resonance processes, which, in turn, underlies enhanced action representation of the observed movements.
本电生理学（EEG）研究调查了属于特定动作范围（芭蕾舞）的费力和不费力运动感知的神经相关性。以前的证据表明，在观察和想象需要大量肌肉用力的人类动作时，心率和呼吸率会增加。此外，TMS（经颅磁刺激）和 EEG 研究表明，在观察费力动作时，肌肉特异性皮质兴奋性增加，晚期事件相关电位增加。在这项研究中，招募了 15 名专业女性芭蕾舞演员和 15 名没有任何舞蹈、体操或武术经验的对照组。他们观看了 326 个短视频，展示了一名男性舞者表演标准的芭蕾舞步，可以是费力的也可以是相对不费力的。要求参与者观察每个剪辑并想象自己身体执行相同的动作。重要的是，他们对刺激属性一无所知。与不费力的运动相比，费力的运动观察在舞者中导致额部 P300 更大，这可能是由于他们对特定步骤的运动视觉专长。此外，在两组中，对费力刺激的反应在后部区域中识别出增强的晚期正性，可能反映了对更大视觉运动信息量的处理。对晚期正性成分进行的源重建 swLORETA 显示，在舞者中，额顶区域的参与度更高，而与任务相关的额部和枕颞部视觉区域在对照组中更活跃。因此，在舞者中，在没有明确指令的情况下，在动作观察期间，费力信息以更精细的方式进行编码。习得的运动知识似乎导致运动视觉共鸣过程，这反过来又增强了观察到的运动的动作表示。
