Hosoya Toshihiko, Nakagawa Nao, Yoneda Taisuke, Maruoka Hisato
Laboratory for Local Neuronal Circuits, RIKEN Center for Brain Science.
Brain Nerve. 2018 Dec;70(12):1381-1388. doi: 10.11477/mf.1416201197.
The mammalian neocortex contains diverse cell types but whether they organize into repeated modular circuits remains unknown. We discovered that major cell types in neocortical layer 5 form a lattice structure in many areas of the brain. Large-scale three-dimensional imaging revealed that distinct types of excitatory and inhibitory neurons form cell type-specific radial clusters termed microcolumns. Microcolumns form a hexagonal lattice tessellating a wide region of the neocortex. Neurons within individual microcolumns exhibit synchronized in vivo activity and visual responses with similar orientation preference and ocular dominance. During early postnatal development, microcolumns are coupled by cell type-specific gap junctions and later received convergent synaptic inputs. Thus, layer 5 neurons organize into a brain-wide modular system providing a template for cortical processing.
哺乳动物的新皮层包含多种细胞类型，但它们是否组织成重复的模块化回路仍不清楚。我们发现，新皮层第5层中的主要细胞类型在大脑的许多区域形成了一种晶格结构。大规模三维成像显示，不同类型的兴奋性和抑制性神经元形成了称为微柱的细胞类型特异性径向簇。微柱形成六边形晶格，镶嵌在新皮层的广泛区域。单个微柱内的神经元在体内表现出同步活动，视觉反应具有相似的方向偏好和眼优势。在出生后早期发育过程中，微柱通过细胞类型特异性缝隙连接耦合，随后接受汇聚的突触输入。因此，第5层神经元组织成一个全脑范围的模块化系统，为皮层处理提供了一个模板。
