小柯机器人

近日，英国伦敦大学学院Kate J. Jeffery、Roddy M. Grieves等研究人员合作揭示大鼠探索三维体积空间时网格细胞发射场的不规则分布。这一研究成果于2021年8月11日在线发表在国际学术期刊《自然—神经科学》上。

研究人员揭示了内嗅皮层网格细胞是如何编码体积空间的。在一个水平面上，网格细胞通常产生多个、空间焦点、近似圆形的发射场，这些发射场的大小和间距均匀，形成一个规则的、紧密包装的六边形阵列。这种空间规则性已被认为是导航计算的基础。在三维空间中，理论上等同的发射模式将是一个有规律的、六边形的紧密包装的均匀大小的球形场。

研究人员发现，大鼠在立体格子中觅食时，网格细胞保持正常的时间发射特征，并产生空间上稳定的发射场。然而，尽管大多数网格场是椭圆形的，但它们更稀疏、更大、大小不一且不规则地排列，即使只考虑与下表面（相当于地板）相邻的场。因此，网格的自我组织是由环境的结构和/或运动能力所决定的，并且网格可能不需要是规律的来支持空间计算。

附：英文原文

Title: Irregular distribution of grid cell firing fields in rats exploring a 3D volumetric space

Author: Grieves, Roddy M., Jedidi-Ayoub, Selim, Mishchanchuk, Karyna, Liu, Anyi, Renaudineau, Sophie, Duvelle, lonore, Jeffery, Kate J.

Issue&Volume: 2021-08-11

Abstract: We investigated how entorhinal grid cells encode volumetric space. On a horizontal surface, grid cells usually produce multiple, spatially focal, approximately circular firing fields that are evenly sized and spaced to form a regular, close-packed, hexagonal array. This spatial regularity has been suggested to underlie navigational computations. In three dimensions, theoretically the equivalent firing pattern would be a regular, hexagonal close packing of evenly sized spherical fields. In the present study, we report that, in rats foraging in a cubic lattice, grid cells maintained normal temporal firing characteristics and produced spatially stable firing fields. However, although most grid fields were ellipsoid, they were sparser, larger, more variably sized and irregularly arranged, even when only fields abutting the lower surface (equivalent to the floor) were considered. Thus, grid self-organization is shaped by the environment’s structure and/or movement affordances, and grids may not need to be regular to support spatial computations.

DOI: 10.1038/s41593-021-00907-4

Source: https://www.nature.com/articles/s41593-021-00907-4

Nature Neuroscience：《自然—神经科学》，创刊于1998年。隶属于施普林格·自然出版集团，最新IF：28.771
官方网址：https://www.nature.com/neuro/
投稿链接：https://mts-nn.nature.com/cgi-bin/main.plex