Bianco Valentina, Finisguerra Alessandra, D'Argenio Giulia, Boscarol Sara, Urgesi Cosimo
Department of Brain and Behavioral Sciences, University of Pavia, 27100 Pavia, Italy; Laboratory of Cognitive Neuroscience, Department of Languages and Literatures, Communication, Education and Society, University of Udine, Udine, Italy.
Scientific Institute, IRCCS E. Medea, Pasian di Prato, Udine, Italy.
Neuroimage. 2024 Aug 15;297:120702. doi: 10.1016/j.neuroimage.2024.120702. Epub 2024 Jun 22.
Contextual information may shape motor resonance and support intention understanding during observation of incomplete, ambiguous actions. It is unclear, however, whether this effect is contingent upon kinematics ambiguity or contextual information is continuously integrated with kinematics to predict the overarching action intention. Moreover, a differentiation between the motor mapping of the intention suggested by context or kinematics has not been clearly demonstrated. In a first action execution phase, 29 participants were asked to perform reaching-to-grasp movements towards big or small food objects with the intention to eat or to move; electromyography from the First Dorsal Interosseous (FDI) and Abductor Digiti Minimi (ADM) was recorded. Depending on object size, the intentions to eat or to move were differently implemented by a whole-hand or a precision grip kinematics, thus qualifying an action-muscle dissociation. Then, in a following action prediction task, the same participants were asked to observe an actor performing the same actions and to predict his/her intention while motor resonance was assessed for the same muscles. Of note, videos were interrupted at early or late action phases, and actions were embedded in contexts pointing toward an eating or a moving intention, congruently or incongruently with kinematics. We found greater involvement of the FDI or ADM in the execution of precision or whole-hand grips, respectively. Crucially, this pattern of activation was mirrored during observation of the same actions in congruent contexts, but it was cancelled out or reversed in the incongruent ones, either when videos were interrupted at either early or long phases of action deployment. Our results extend previous evidence by showing that contextual information shapes motor resonance not only under conditions of perceptual uncertainty but also when more informative kinematics is available.
情境信息可能会塑造运动共鸣，并在观察不完整、模糊的动作时支持意图理解。然而，尚不清楚这种效应是否取决于运动学的模糊性，或者情境信息是否会与运动学持续整合以预测总体动作意图。此外，情境或运动学所暗示意图的运动映射之间的差异尚未得到明确证明。在第一个动作执行阶段，29名参与者被要求朝着大或小的食物物体进行伸手抓握动作，意图是进食或移动；记录了第一背侧骨间肌（FDI）和小指展肌（ADM）的肌电图。根据物体大小，进食或移动的意图通过全手抓握或精确抓握运动学以不同方式实现，从而形成动作 - 肌肉解离。然后，在接下来的动作预测任务中，要求相同的参与者观察一名演员执行相同的动作，并预测其意图，同时评估相同肌肉的运动共鸣。值得注意的是，视频在动作的早期或晚期阶段被打断，并且动作被嵌入指向进食或移动意图的情境中，与运动学一致或不一致。我们发现FDI或ADM分别在精确抓握或全手抓握的执行中参与度更高。至关重要的是，在观察相同动作在一致情境中的过程中，这种激活模式得到了反映，但在不一致的情境中，无论是视频在动作展开的早期还是晚期阶段被打断，这种模式都会被消除或反转。我们的结果扩展了先前的证据，表明情境信息不仅在感知不确定的条件下，而且在有更多信息丰富的运动学时，都会塑造运动共鸣。
