标题： 局部皮层网络的细胞类型特异性连接解释了神经元活动的显著特征 显示英文标题

标题： The cell-type specific connectivity of the local cortical network explains prominent features of neuronal activity

摘要： 在过去十年中，局部皮层网络的细胞类型特异性连接和活动已被实验详细表征。 同时，建模已被确立为一种将网络结构与活动动态相关联的工具。 尽管可用的连接图已被用于各种计算研究，但模拟活动的显著特征，如自发放电率，并不与实验结果一致。 在这里，我们表明这种不一致来自于连接图的不完整性。 我们对最全面的连接图（Thomson 等，2002；Binzegger 等，2004）进行比较，揭示了它们的主要差异：横向采样范围和目标细胞的具体选择。 考虑到这些因素，我们编制了一个综合的连接图，并通过局部分层皮层网络的全尺度模型进行模拟分析。 模拟的自发活动是异步且不规则的，细胞类型特异的自发放电率与清醒动物的体内记录一致，包括第2/3层兴奋性细胞的低放电率。 同样，由短暂丘脑输入引发的激活模式再现了最近的体内测量结果。 模拟结果与实验的对应关系基于对特定目标类型选择的考虑，从而基于大量可用连接数据的整合。 细胞类型特异的层级输入结构以及前馈和反馈连接的结合揭示了兴奋与抑制的相互作用如何塑造局部皮层网络的自发和诱发活动。 显示英文摘要

摘要： In the past decade, the cell-type specific connectivity and activity of local cortical networks have been characterized experimentally to some detail. In parallel, modeling has been established as a tool to relate network structure to activity dynamics. While the available connectivity maps have been used in various computational studies, prominent features of the simulated activity such as the spontaneous firing rates do not match the experimental findings. Here, we show that the inconsistency arises from the incompleteness of the connectivity maps. Our comparison of the most comprehensive maps (Thomson et al., 2002; Binzegger et al., 2004) reveals their main discrepancies: the lateral sampling range and the specific selection of target cells. Taking them into account, we compile an integrated connectivity map and analyze the unified map by simulations of a full scale model of the local layered cortical network. The simulated spontaneous activity is asynchronous irregular and the cell-type specific spontaneous firing rates are in agreement with in vivo recordings in awake animals, including the low rate of layer 2/3 excitatory cells. Similarly, the activation patterns evoked by transient thalamic inputs reproduce recent in vivo measurements. The correspondence of simulation results and experiments rests on the consideration of specific target type selection and thereby on the integration of a large body of the available connectivity data. The cell-type specific hierarchical input structure and the combination of feed-forward and feedback connections reveal how the interplay of excitation and inhibition shapes the spontaneous and evoked activity of the local cortical network.