En route to delineating hippocampal roles in spatial learning.
En route to delineating hippocampal roles in spatial learning.
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正在描绘海马在空间学习中的作用。
DOI：
10.1016/j.bbr.2019.111936
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发表时间：
2019
影响因子：
2.7
通讯作者：
Poulter S
中科院分区：
文献类型：
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作者：
Poulter S
海马在空间学习任务中所起的确切作用，如Morris水迷宫（MWM），还没有完全了解。一种理论认为，海马体并不是“知道哪里”所必需的，而是“到达那里”的关键。为了探索这个想法在MWM，我们操纵“到达那里”的变量，如被动运输或主动游泳到隐藏的平台，在大鼠与海马nasis.Our结果表明，对于完整的大鼠，自我运动线索途中隐藏的目标是一个必要的组成部分，为“地方学习”的进展。具体来说，完整的大鼠不能学习隐藏的目标位置，当被动地运送到它，尽管广泛的训练。然而，当大鼠被给予海马损伤，或在运输过程中被放置在一个不透光的盒子里，以隐藏的目标，被动放置空间学习促进。在随后的实验中，地点导航的“到达那里”部分被简化了，通过放置两个头顶地标，其中一个充当信标。当“到达那里”以这种方式变得更容易时，海马损伤不会导致“知道目标在哪里”的缺陷。事实上，与被动放置空间学习中观察到的促进作用相似，海马损伤相对于对照组改善了地标学习。最后，证明我们的病变是足够有害的，campal-lesioned大鼠受损，如预测的那样，在环境边界为基础的学习任务。我们解释这些结果在多个记忆系统之间的竞争，和自我产生的运动线索在海马空间映射的重要性。
The precise role played by the hippocampus in spatial learning tasks, such as the Morris Water Maze (MWM), is not fully understood. One theory is that the hippocampus is not required for ‘knowing where’ but rather is crucial in ‘getting there’. To explore this idea in the MWM, we manipulated ‘getting there’ variables, such as passive transport or active swimming towards the hidden platform, in rats with and without hippocampal lesions.Our results suggested that for intact rats, self-motion cues enroute to the hidden goal were a necessary component for ‘place learning’ to progress. Specifically, intact rats could not learn the hidden goal location, when passively transported to it, despite extensive training. However, when rats were either given hippocampal lesions, or placed in a light-tight box during transportation to the hidden goal, passive-placement spatial learning was facilitated. In a subsequent experiment, the ‘getting there’ component of place navigation was simplified, via the placement of two overhead landmarks, one of which served as a beacon. When ‘getting there’ was made easier in this way, hippocampal lesions did not induce deficits in ‘knowing where’ the goal was. In fact, similar to the facilitation observed in passive-placement spatial learning, hippocampal lesions improved landmark learning relative to controls. Finally, demonstrating that our lesions were sufficiently deleterious, hippocampal-lesioned rats were impaired, as predicted, in an environmental-boundary based learning task. We interpret these results in terms of competition between multiple memory systems, and the importance of self-generated motion cues in hippocampal spatial mapping.