School of Psychology, The University of Queensland, St Lucia, Australia.
PLoS One. 2011;6(10):e26945. doi: 10.1371/journal.pone.0026945. Epub 2011 Oct 28.
The 'mirror neuron system' (MNS), located within inferior parietal lobe (IPL) and inferior frontal gyrus (IFG), creates an internal motor representation of the actions we see and has been implicated in imitation. Recently, the MNS has been implicated in non-identical responses: when the actions we must execute do not match those that we observe. However, in such conflicting situations non action-specific cognitive control networks also located in frontoparietal regions may be involved. In the present functional magnetic resonance imaging (fMRI) study participants made both similar and dissimilar actions within two action contexts: imitative and complementary. We aimed to determine whether activity within IPL/IFG depends on (i) responding under an imitative versus complementary context (ii) responding with similar versus dissimilar responses, and (iii) observing hand actions versus symbolic arrow cue stimuli. Activity within rIPL/rIFG regions was largest during observation of hand actions compared with arrow cues. Specifically, rIPL/rIFG were recruited only during the imitative context, when participants responded with similar actions. When responding to symbolic arrow cues, rIPL/rIFG activity increased during dissimilar responses, reflecting increased demands placed on general cognitive control mechanisms. These results suggest a specific role of rIPL/rIFG during imitation of hand actions, and also a general role of frontoparietal areas in mediating dissimilar responses to both hand actions and symbolic stimuli. We discuss our findings in relation to recent work that has examined the role of frontoparietal brain structures in joint-actions and inter-actor cooperation. We conclude that the specific brain regions identified here to show increased activation during action observation conditions are likely to form part of a mechanism specifically involved in matching observed actions directly with internal motor plans. Conversely, observation of arrow cues recruited part of a wider cognitive control network involved in the rapid remapping of stimulus-response associations.
“镜像神经元系统”（MNS）位于顶下小叶（IPL）和额下回（IFG）内，创建了我们所看到的动作的内部运动表示，并且与模仿有关。最近，MNS 与非相同反应有关：当我们必须执行的动作与我们观察到的动作不匹配时。然而，在这种冲突情况下，位于顶-额区域的非动作特异性认知控制网络也可能参与其中。在本功能磁共振成像（fMRI）研究中，参与者在两个动作情境中进行相似和不相似的动作：模仿和补充。我们的目的是确定 IPL/IFG 内的活动是否取决于（i）在模仿与补充情境下进行反应（ii）用相似或不相似的反应进行反应，以及（iii）观察手部动作与符号箭头提示刺激。与箭头提示相比，rIPL/rIFG 区域在观察手部动作时的活动最大。具体而言，rIPL/rIFG 仅在模仿情境下被招募，此时参与者用相似的动作进行反应。当对符号箭头提示做出反应时，rIPL/rIFG 的活动在不相似的反应中增加，反映出对一般认知控制机制的需求增加。这些结果表明 rIPL/rIFG 在模仿手部动作中具有特定的作用，并且顶-额区域在介导对手部动作和符号刺激的不相似反应方面也具有一般作用。我们根据最近研究工作讨论了我们的发现，该研究工作检查了顶-额脑结构在联合动作和互动者合作中的作用。我们得出结论，在观察动作条件下显示出增加的激活的特定脑区可能是直接将观察到的动作与内部运动计划相匹配的机制的一部分。相反，箭头提示的观察招募了涉及刺激-反应关联快速重新映射的更广泛认知控制网络的一部分。
