Abstract

Interpersonal motor resonance (IMR) is a common putative index of the mirror neuron system (MNS), a network containing specialised cells that fire during both action execution and observation. Visual content inputs to the MNS, however, it is unclear whether visual behaviours mediate the putative MNS response. We aimed to examine gaze effects on IMR during action observation. Neurotypical adults (N = 99; 60 female) underwent transcranial magnetic stimulation, electromyography, and eye-tracking during the observation of videos of actors performing grasping actions. IMR was measured as a percentage change in motor evoked potentials (MEPs) of the first dorsal interosseous muscle during action observation relative to baseline. MEP facilitation was observed during action observation, indicating IMR (65.43%, SE = 11.26%, P < 0.001). Fixations occurring in biologically relevant areas (face/hand/arm) yielded significantly stronger IMR (81.03%, SE = 14.15%) than non-biological areas (63.92%, SE = 14.60, P = 0.012). This effect, however, was only evident in the first of four experimental blocks. Our results suggest that gaze fixation can modulate IMR, but this may be affected by the salience and novelty of the observed action. These findings have important methodological implications for future studies in both clinical and healthy populations.

中文翻译：

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动作观察期间的凝视行为是否可以预测人际运动共振？

摘要

人际运动共振 (IMR) 是镜像神经元系统 (MNS) 的一个常见推定指标，MNS 是一个包含在动作执行和观察期间发射的特殊细胞的网络。然而，对于 MNS 的视觉内容输入，尚不清楚视觉行为是否介导了假定的 MNS 反应。我们的目的是在动作观察期间检查凝视对 IMR 的影响。神经型成人 ( N = 99; 60 名女性）在观察演员表演抓握动作的视频期间接受了经颅磁刺激、肌电图和眼动追踪。IMR 测量为在动作观察期间第一背侧骨间肌的运动诱发电位 (MEP) 相对于基线的百分比变化。在行动观察期间观察到MEP促进，表明IMR（65.43％，SE = 11.26％，P  <0.001）。发生在生物相关区域（面部/手/手臂）的固定产生显着更强的 IMR（81.03%，SE = 14.15%）比非生物区域（63.92%，SE = 14.60，P = 0.012)。然而，这种效果仅在四个实验块中的第一个中很明显。我们的结果表明凝视可以调节 IMR，但这可能会受到观察到的动作的显着性和新颖性的影响。这些发现对临床和健康人群的未来研究具有重要的方法学意义。