Directional control of hippocampal place fields
Directional control of hippocampal place fields
复制标题
DOI：
10.1007/s002210050206
复制
发表时间：
1997-10-01
影响因子：
2
通讯作者：
OKeefe, JM
中科院分区：
文献类型：
--
作者：
Jeffery, KJ;Donnett, JG;OKeefe, JM
每当大鼠处于特定位置时，海马体中的锥体细胞就会被激活，这表明海马体保持着对环境的表征。位置细胞的感受野（位置野）在很大程度上取决于大鼠与环境墙的距离。由于这些墙壁有时只能通过它们相对于外部房间的方向来区分，因此已经假设极化方向输入使细胞能够在对称环境中将它们的场偏离中心。我们通过独立于其他线索控制大鼠的内部方向感来测试这一假设，看看操纵这种感觉本身是否会产生相应的位置场方向改变。记录位置细胞，而大鼠觅食在一个矩形框中，在外部房间线索的存在或不存在。在房间线索被掩盖的情况下，老鼠和盒子一起缓慢旋转会导致磁场相应地旋转。单独将记录盒旋转180度很少会导致相应的场旋转，而将大鼠单独旋转180度，然后将其放入记录盒中，几乎总是会导致相应的场旋转。这表明位置场定向可以通过控制大鼠的内部方向感来控制，并且它为方向感的感觉基础的心理物理探索打开了大门。当房间线索，远端视觉线索占主导地位的内部线索，在建立位置场取向。
Pyramidal cells in the rat hippocampus fire whenever the animal is in a particular place, suggesting that the hippocampus maintains a representation of the environment. Receptive fields of place cells (place fields) are largely determined by the distance of the rat from environmental walls. Because these walls are sometimes distinguishable only by their orientation with respect to the outside room, it has been hypothesised that a polarising directional input enables the cells to locate their fields off-centre in an otherwise symmetrical environment. We tested this hypothesis by gaining control of the rat's internal directional sense, independently of other cues, to see whether manipulating this sense could, by itself, produce a corresponding alteration in place field orientation. Place cells were recorded while rats foraged in a rectangular box, in the absence or presence of external room cues. With room cues masked, slow rotation of the rat and the box together caused the fields to rotate accordingly. Rotating the recording box alone by 180 degrees rarely caused corresponding field rotation, while rotating the rat alone 180 degrees outside the environment and then replacing it in the recording box almost always resulted in a corresponding rotation of the fields. This shows that place field orientation can be controlled by controlling the internal direction-sense of the rat, and it opens the door to psychophysical exploration of the sensory basis of the direction sense. When room cues were present, distal visual cues predominated over internal cues in establishing place field orientation.