Functicnal significance of the medial paiietal areas for the cognitive map and navigation

认知地图是大脑中大规模环境的存储表示。当我们在一个大规模的环境中行动时，认知地图是必要的，但还不够;因为它太抽象了，无法为我们的导航计划一个特定的路线图。当我们开车去办公室时，我们可以下意识地走正确的路线，在每个十字路口转弯或直行。这种现象表明，除了大脑中的“认知地图”外，我们可能还有一个在给定位置必须做的事情的内部列表。这个内部列表被称为“路线知识”，可以访问它以便在大规模环境中导航。人类的病变和神经影像学研究表明，内侧顶叶区（MPR），包括压后和后扣带回皮质，是关键参与导航的基础上的路线知识。为了研究灵长类动物在大环境中导航的神经机制，在实验装置内的大环境中， ...更多信息 P必须建立。在这项研究中，我们使用虚拟现实技术来克服这个问题，并记录了一个单一的单位活动，从猴子MPR，而猴子导航在虚拟环境中没有执行任何实际的运动。为了检查神经基础的路线知识，其中一个可以到达一个目的地，我们记录了猴子在虚拟环境中主动导航时，其内侧顶叶区（MPR）中580个神经元的活动。这些神经元中有180个（31%）对猴子在虚拟环境中的运动表现出明显的反应。在这些反应性神经元中，77%（139-180）显示出与特定位置处的特定运动相关的反应（导航神经元），8%（14-180）显示出与特定运动相关的反应（运动选择性神经元），其余27个神经元（15%）是非选择性的。我们发现导航神经元对相同位置的相同运动的反应取决于猴子当前采取的路线，即以路线选择的方式进行调制（139个导航神经元中的59个测试神经元中的32个，路线选择性导航神经元。蝇蕈醇对MPR神经元的可逆失活导致猴子在导航任务试验期间迷路。这些结果表明，MPR通过整合位置信息和自我运动信息在基于路线的导航中起着至关重要的作用。少

A cognitive map is a stored representation of a large-scale environment in the brain. When we behave in a large-scale environment, a cognitive map is necessary but not sufficient ; because it is too abstract to plan a specific route map for our navigation. When we drive to our office, we can take the correct route subconsciously, making a turn or going straight at each intersection. This phenomenon suggests we may have an internal list of what we have to do at a given location in addition to a "cognitive map" in our brain. This internal list is known as "route knowledge" and is accessed to be able to navigate ourselves in a large-scale environment. Lesion and neuroimaging studies of humans suggest that the medial parietal region (MPR), including the retrosplenial and posterior cingulate cortices, is critically involved in navigation based on route knowledge. To study the neural mechanisms of navigation in a large environment in primates, a large environment within the experimental setu … More p needs to be built. In this study, we used a virtual reality technique to overcome this problem and recorded a single unit activity from the monkey MPR while the monkey navigated in the virtual environment without performing any actual movement.To examine the neural basis of route knowledge by which one can reach one's destination, we recorded the activity of 580 neurons in the monkey medial parietal region (MPR) while monkeys actively navigated through a virtual environment. One hundred eighty of these neurons (31%) showed significant responses to the monkeys' movements in the virtual environment. Of these responsive neurons, 77% (139-180) showed responses associated with a specific movement at a specific location (navigation neurons), 8% (14-180) showed responses associated with a specific movement (movement- selective neurons), and the remaining 27 neurons (15%) were nonselective. We found navigation neurons whose responses to the same movement at the same location were modulated depending on the route that the monkey was currently taking, that is, in a route-selective manner (32 of 59 tested neurons among 139 navigation neurons, route-selective navigation neurons. The reversible inactivation of MPR neurons by muscimol resulted in a monkey becoming lost during the navigation task trial. These results suggest that MPR plays a critical role in route-based navigation by integrating location information and self-movement information. Less