German Center for Neurodegenerative Diseases (DZNE) Dresden, Germany ; CRTD - DFG Research Center for Regenerative Therapies Dresden, Technische Universität Dresden Dresden, Germany.
Front Neurosci. 2013 May 3;7:63. doi: 10.3389/fnins.2013.00063. eCollection 2013.
The Morris water maze represents the de-facto standard for testing hippocampal function in laboratory rodents. In the field of adult hippocampal neurogenesis, however, using this paradigm to assess the functional relevance of the new neurons yielded surprisingly inconsistent results. While some authors found aspects of water maze performance to be linked to adult neurogenesis, others obtained different results or could not demonstrate any effect of manipulating adult neurogenesis. In this review we discuss evidence that the large diversity of protocols and setups used is an important aspect in interpreting the differences in the results that have been obtained. Even simple parameters such as pool size, number, and configuration of visual landmarks, or number of trials can become highly relevant for getting the new neurons involved at all. Sets of parameters are often chosen with implicit or explicit concepts in mind and these might lead to different views on the function of adult-generated neurons. We propose that the classical parameters usually used to measure spatial learning performance in the water maze might not be particularly well-suited to sensitively and specifically detect the supposedly highly specific functional changes elicited by the experimental modulation of adult hippocampal neurogenesis. As adult neurogenesis is supposed to affect specific aspects of information processing only in the hippocampus, any claim for a functional relevance of the new neurons has to be based on hippocampus-specific parameters. We also placed a special emphasis on the fact that the dentate gyrus (DG) facilitates the differentiation between contexts as opposed to just differentiating places. In conclusion, while the Morris water maze has proven to be one of the most effective testing paradigms to assess hippocampus-dependent spatial learning, new and more specific questions ask for new parameters. Therefore, the full potential of the water maze task remains to be tapped.
水迷宫是检测实验动物海马功能的标准方法。然而，在成年海马神经发生领域，使用该范式评估新神经元的功能相关性得出的结果却出人意料地不一致。虽然一些作者发现水迷宫性能的某些方面与成年神经发生有关，但其他作者得到了不同的结果，或者无法证明操纵成年神经发生有任何影响。在这篇综述中，我们讨论了证据表明，使用的协议和设置的多样性是解释已经获得的结果差异的一个重要方面。即使是一些简单的参数，如水池大小、视觉标志物的数量和配置，或试验次数，对于让新神经元参与其中也变得非常重要。参数集通常是基于隐含或显式的概念来选择的，这些概念可能会导致对成年产生的神经元功能的不同看法。我们提出，经典的参数通常用于测量水迷宫中的空间学习性能，可能不太适合敏感和特异性地检测实验调节成年海马神经发生所引起的高度特定的功能变化。由于成年神经发生应该只影响海马体中特定方面的信息处理，任何关于新神经元功能相关性的说法都必须基于海马体特异性参数。我们还特别强调了一个事实，即齿状回（DG）有助于区分上下文，而不仅仅是区分位置。总之，尽管 Morris 水迷宫已被证明是评估海马体依赖空间学习的最有效测试范式之一，但新的和更具体的问题需要新的参数。因此，水迷宫任务的全部潜力还有待挖掘。
