Fragmentation of grid cell maps in a multicompartment environment
Fragmentation of grid cell maps in a multicompartment environment
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DOI：
10.1038/nn.2396
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发表时间：
2009-10-01
影响因子：
25
通讯作者：
Moser, Edvard I.
中科院分区：
文献类型：
--
作者：
Derdikman, Dori;Whitlock, Jonathan R.;Moser, Edvard I.
为了确定内嗅觉空间表征是连续的还是零散的，我们记录了大鼠在一堆相互连接的、相同形状和方向的之字形空间(发夹迷宫)中运行时网格细胞中的神经活动。在所有沿同一方向奔跑的舱室中，空间射击场的分布明显相似，这意味着网格表示被分割成重复的子图。在不同手臂之间的转换中，相邻位置的活动相关性最小，这表明地图在转折点有规律地分裂。我们在海马区的位置细胞之间看到了类似的不连续。在没有内壁的情况下，当大鼠遵循类似的轨迹时，没有观察到碎片，这意味着仅凭刻板印象的行为不能解释分区。这些结果表明，空间环境在内嗅觉皮质和海马体中被表示为与空间几何结构相对应的离散的子图的马赛克。
To determine whether entorhinal spatial representations are continuous or fragmented, we recorded neural activity in grid cells while rats ran through a stack of interconnected, zig-zagged compartments of equal shape and orientation (a hairpin maze). The distribution of spatial firing fields was markedly similar across all compartments in which running occurred in the same direction, implying that the grid representation was fragmented into repeating submaps. Activity at neighboring positions was least correlated at the transitions between different arms, indicating that the map split regularly at the turning points. We saw similar discontinuities among place cells in the hippocampus. No fragmentation was observed when the rats followed similar trajectories in the absence of internal walls, implying that stereotypic behavior alone cannot explain the compartmentalization. These results indicate that spatial environments are represented in entorhinal cortex and hippocampus as a mosaic of discrete submaps that correspond to the geometric structure of the space.