Social Brain Laboratory, Department of Neuroscience, University Medical Center Groningen, University of Groningen, 9713 AW, Groningen, The Netherlands.
Proc Natl Acad Sci U S A. 2010 May 18;107(20):9388-93. doi: 10.1073/pnas.1001791107. Epub 2010 May 3.
Both the putative mirror neuron system (pMNS) and the ventral medial prefrontal cortex (vmPFC) are deemed important for social interaction: the pMNS because it supposedly "resonates" with the actions of others, the vmPFC because it is involved in mentalizing. Strictly speaking, the resonance property of the pMNS has never been investigated. Classical functional MRI experiments have only investigated whether pMNS regions augment their activity when an action is seen or executed. Resonance, however, entails more than only "going on and off together". Activity in the pMNS of an observer should continuously follow the more subtle changes over time in activity of the pMNS of the actor. Here we directly explore whether such resonance indeed occurs during continuous streams of actions. We let participants play the game of charades while we measured brain activity of both gesturer and guesser. We then applied a method to localize directed influences between the brains of the participants: between-brain Granger-causality mapping. Results show that a guesser's brain activity in regions involved in mentalizing and mirroring echoes the temporal structure of a gesturer's brain activity. This provides evidence for resonance theories and indicates a fine-grained temporal interplay between regions involved in motor planning and regions involved in thinking about the mental states of others. Furthermore, this method enables experiments to be more ecologically valid by providing the opportunity to leave social interaction unconstrained. This, in turn, would allow us to tap into the neural substrates of social deficits such as autism spectrum disorder.
假定的镜像神经元系统（pMNS）和腹内侧前额叶皮层（vmPFC）都被认为对社交互动很重要：pMNS 因为它据称会“共鸣”他人的动作，vmPFC 因为它涉及到心理化。严格来说，pMNS 的共振特性从未被研究过。经典的功能磁共振成像实验只研究了当看到或执行动作时，pMNS 区域是否会增强其活动。然而，共鸣不仅仅是“一起开和关”。观察者的 pMNS 中的活动应该随着演员的 pMNS 中的活动随时间的微妙变化而持续跟随。在这里，我们直接探索在连续的动作流中是否确实发生了这种共鸣。我们让参与者玩猜谜游戏，同时测量手势者和猜测者的大脑活动。然后，我们应用一种方法来定位参与者之间大脑之间的定向影响：大脑间格兰杰因果关系映射。结果表明，猜测者大脑中参与心理化和镜像的区域的活动反映了手势者大脑活动的时间结构。这为共鸣理论提供了证据，并表明了参与运动规划的区域与思考他人心理状态的区域之间的精细时间相互作用。此外，这种方法通过提供不受限制的社交互动机会，使实验更具生态有效性。反过来，这将使我们能够利用自闭症谱系障碍等社交缺陷的神经基础。
