Kavli Institute for Systems Neuroscience and Centre for the Biology of Memory, Norwegian Brain Centre, Norwegian University of Science and Technology, Trondheim, Norway.
Nat Neurosci. 2013 Mar;16(3):318-24. doi: 10.1038/nn.3310. Epub 2013 Jan 20.
Grid cells in layer II of the medial entorhinal cortex form a principal component of the mammalian neural representation of space. The firing pattern of a single grid cell has been hypothesized to be generated through attractor dynamics in a network with a specific local connectivity including both excitatory and inhibitory connections. However, experimental evidence supporting the presence of such connectivity among grid cells in layer II is limited. Here we report recordings from more than 600 neuron pairs in rat entorhinal slices, demonstrating that stellate cells, the principal cell type in the layer II grid network, are mainly interconnected via inhibitory interneurons. Using a model attractor network, we demonstrate that stable grid firing can emerge from a simple recurrent inhibitory network. Our findings thus suggest that the observed inhibitory microcircuitry between stellate cells is sufficient to generate grid-cell firing patterns in layer II of the medial entorhinal cortex.
网格细胞在大脑内侧面的内嗅皮层的第二层形成了哺乳动物对空间进行神经表示的主要组成部分。单个网格细胞的发射模式被假设是通过具有特定局部连接的网络中的吸引子动力学产生的，该网络包括兴奋性和抑制性连接。然而，支持在第二层的网格细胞中存在这种连接的实验证据是有限的。在这里，我们报告了在大鼠内嗅皮层切片中记录的 600 多个神经元对，证明了在网格网络中起主要作用的星状细胞主要通过抑制性中间神经元相互连接。使用一个模型吸引子网络，我们证明了稳定的网格发射可以从简单的递归抑制网络中产生。因此，我们的研究结果表明，观察到的星状细胞之间的抑制性微电路足以在大脑内侧面的内嗅皮层的第二层产生网格细胞的发射模式。
