RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Science. 2017 Nov 3;358(6363):610-615. doi: 10.1126/science.aam6125.
The mammalian neocortex contains many cell types, but whether they organize into repeated structures has been unclear. We discovered that major cell types in neocortical layer 5 form a lattice structure in many brain areas. Large-scale three-dimensional imaging revealed that distinct types of excitatory and inhibitory neurons form cell type-specific radial clusters termed microcolumns. Thousands of microcolumns, in turn, are patterned into a hexagonal mosaic tessellating diverse regions of the neocortex. Microcolumn neurons demonstrate synchronized in vivo activity and visual responses with similar orientation preference and ocular dominance. In early postnatal development, microcolumns are coupled by cell type-specific gap junctions and later serve as hubs for convergent synaptic inputs. Thus, layer 5 neurons organize into a brainwide modular system, providing a template for cortical processing.
哺乳动物新皮层包含许多细胞类型，但它们是否形成重复的结构尚不清楚。我们发现，新皮层 5 层的主要细胞类型在许多脑区形成晶格结构。大规模的三维成像显示，不同类型的兴奋性和抑制性神经元形成细胞类型特异性的径向簇，称为微柱。数以千计的微柱又被组织成六边形镶嵌图案，构成新皮层的不同区域。微柱神经元表现出与相似方位偏好和眼优势相关的同步活体活动和视觉反应。在出生后的早期发育过程中，微柱通过细胞类型特异性的缝隙连接耦合，随后作为会聚突触输入的枢纽。因此，5 层神经元组织成一个全脑范围的模块化系统，为皮质处理提供了模板。
