Department of Zoology, Faculty of Life Sciences, Tel-Aviv University, Ramat-Aviv 69978, Israel.
Behav Brain Res. 2011 Dec 1;225(2):449-54. doi: 10.1016/j.bbr.2011.07.055. Epub 2011 Aug 5.
We show here that the global geometry of the environment affects the shape of the paths of travel in rats. To examine this, individual rats were introduced into an unfamiliar arena. One group of rats (n=8) was tested in a square arena (2 m × 2 m), and the other group (n=8) in a round arena (2 m diameter). Testing was in a total darkness, since in the absence of visual information the geometry is not perceived immediately and the extraction of environment shape is slower. We found that while the level of the rats' activity did not seem to differ between both arenas, path shape differed significantly. When traveling along the perimeter, path shape basically followed the arena walls, with perimeter paths curving along the walls of the round arena, while being straight along the walls of the square arena. A similar impact of arena geometry was observed for travel away from the arena walls. Indeed, when the rats abandoned the arena walls to crosscut through the center of the arena, their center paths were circuitous in the round arena and relatively straight in the square arena. We suggest that the shapes of these paths are exploited for the same spatial task: returning back to a familiar location in the unsighted environment.
我们在这里展示了环境的全局几何形状会影响大鼠行进路径的形状。为了研究这一点，我们将单个大鼠引入到一个陌生的环境中。一组大鼠（n=8）在正方形场地（2 m × 2 m）中进行测试，另一组（n=8）在圆形场地（2 m 直径）中进行测试。测试是在完全黑暗的环境中进行的，因为在没有视觉信息的情况下，大鼠无法立即感知到环境的几何形状，因此对环境形状的提取速度会较慢。我们发现，尽管两组大鼠的活动水平似乎没有差异，但它们的行进路径形状却有明显的差异。当沿着场地边缘行进时，路径形状基本沿着场地墙壁，圆形场地的边缘路径沿墙壁弯曲，而正方形场地的边缘路径则是直的。在远离场地墙壁的行进过程中，也观察到了类似的场地几何形状的影响。事实上，当大鼠离开场地墙壁，横穿场地中心时，它们的中心路径在圆形场地中呈迂回状，而在正方形场地中则相对直。我们认为这些路径的形状被用于相同的空间任务：在视线之外的环境中返回到熟悉的位置。
