The posterior parietal cortex (PPC) and frontal motor areas comprise a cortical network supporting goal-directed behaviour, with functions including sensorimotor transformations and decision making. In primates, this network links performed and observed actions via mirror neurons, which fire both when individuals perform an action and when they observe the same action performed by a conspecific. Mirror neurons are believed to be important for social learning, but it is not known whether mirror-like neurons occur in similar networks in other social species, such as rodents, or if they can be measured in such models using paradigms where observers passively view a demonstrator. Therefore, we imaged Ca²⁺ responses in PPC and secondary motor cortex (M2) while mice performed and observed pellet-reaching and wheel-running tasks, and found that cell populations in both areas robustly encoded several naturalistic behaviours. However, neural responses to the same set of observed actions were absent, although we verified that observer mice were attentive to performers and that PPC neurons responded reliably to visual cues. Statistical modelling also indicated that executed actions outperformed observed actions in predicting neural responses. These results raise the possibility that sensorimotor action recognition in rodents could take place outside of the parieto-frontal circuit, and underscore that detecting socially-driven neural coding depends critically on the species and behavioural paradigm used.

顶叶后皮质（PPC）和额叶运动区包括一个支持目标定向行为的皮质网络，其功能包括感觉运动转换和决策。在灵长类动物中，该网络通过镜像神经元链接已执行和已观察到的动作，这在个体执行某项动作和观察到同种动物执行的同一动作时都会触发。镜像神经元被认为对社交学习很重要，但尚不清楚镜像类神经元是否出现在其他社会物种（例如啮齿动物）的类似网络中，或者是否可以在这种模型中使用观察者被动观察动物的范例进行测量。示威者。因此，我们拍摄了Ca ²⁺小鼠在执行PPC和次要运动皮层（M2）的反应时，观察到了到达小球和滚轮的任务，发现这两个区域中的细胞群都可以强有力地编码几种自然行为。但是，尽管我们证实观察者的小鼠对表演者很专心，并且PPC神经元对视觉提示的反应可靠，但对同一组观察到的动作却没有神经反应。统计模型还表明，在预测神经反应方面，执行的动作胜过观察到的动作。这些结果增加了在啮齿动物中感觉运动动作识别可能发生在额叶额叶回路之外的可能性，并强调了检测社会驱动的神经编码关键取决于所用物种和行为范式。