Division of Applied System Neuroscience, Advanced Medical Research Center, Nihon University Graduate School of Medical Science, Itabashi, Tokyo 173-8610, Japan.
Cereb Cortex. 2010 Apr;20(4):846-58. doi: 10.1093/cercor/bhp147. Epub 2009 Jul 20.
To investigate the role of the medial parietal region (MPR), comprising area 7 m and the retrosplenial and posterior cingulate cortices, in spatial navigation, we analyzed the spatial aspect of the responses of the MPR neurons in monkeys while they actively performed a navigation task in a virtual environment. One-third of the analyzed MPR neurons were activated depending on the location of the monkeys in the environment, that is, showed place-selective responses. Some neurons showed varying responses based on the starting point (SP) or destination. We further investigated the responses of the place-selective neurons when the monkeys were shown animations of the entire navigation route, including the preferred field, and a segment of the route, including an area around the preferred field, and a still image of the preferred field. We observed that the responses of some place-selective neurons reduced when the monkeys viewed the preferred field in the segmented animation or in the still image compared with when they viewed the entire animation. These results suggested that the knowledge about the SP or destination, that is, context, is necessary to activate place-selective neurons. The effect of such contextual information suggests that the MPR plays decisive roles in spatial processing such as navigation.
为了研究包括 7m 区、后扣带回和后顶叶皮质在内的内侧顶叶区域（MPR）在空间导航中的作用，我们分析了猴子在虚拟环境中主动执行导航任务时 MPR 神经元的空间响应。分析的 MPR 神经元中有三分之一取决于猴子在环境中的位置而被激活，也就是说，表现出位置选择性反应。一些神经元根据起点（SP）或目的地表现出不同的反应。当猴子观看整个导航路线的动画，包括首选区域，以及路线的一段，包括首选区域周围的区域，以及首选区域的静态图像时，我们进一步研究了位置选择性神经元的反应。我们观察到，与观看整个动画相比，当猴子在分段动画或静态图像中观看首选区域时，一些位置选择性神经元的反应减少。这些结果表明，关于 SP 或目的地的知识，即上下文，对于激活位置选择性神经元是必要的。这种上下文信息的影响表明，MPR 在空间处理（如导航）中起着决定性的作用。
