Vass Lindsay K, Epstein Russell A
Department of Psychology, University of Pennsylvania, Philadelphia, PA, USA.
Cereb Cortex. 2017 Feb 1;27(2):1457-1471. doi: 10.1093/cercor/bhv343.
Spatial knowledge about an environment can be cued from memory by perception of a visual scene during active navigation or by imagination of the relationships between nonvisible landmarks, such as when providing directions. It is not known whether these different ways of accessing spatial knowledge elicit the same representations in the brain. To address this issue, we scanned participants with fMRI, while they performed a judgment of relative direction (JRD) task that required them to retrieve real-world spatial relationships in response to either pictorial or verbal cues. Multivoxel pattern analyses revealed several brain regions that exhibited representations that were independent of the cues to access spatial memory. Specifically, entorhinal cortex in the medial temporal lobe and the retrosplenial complex (RSC) in the medial parietal lobe coded for the heading assumed on a particular trial, whereas the parahippocampal place area (PPA) contained information about the starting location of the JRD. These results demonstrate the existence of spatial representations in RSC, ERC, and PPA that are common to visually guided navigation and spatial imagery.
在主动导航过程中，通过对视觉场景的感知，或者在提供方向等情况下，通过想象不可见地标之间的关系，可以从记忆中唤起关于环境的空间知识。目前尚不清楚这些获取空间知识的不同方式是否会在大脑中引发相同的表征。为了解决这个问题，我们在参与者执行相对方向判断（JRD）任务时，用功能磁共振成像（fMRI）对他们进行扫描，该任务要求他们根据图片或语言线索检索现实世界中的空间关系。多体素模式分析揭示了几个脑区，这些脑区表现出的表征与获取空间记忆的线索无关。具体而言，内侧颞叶的内嗅皮层和内侧顶叶的压后复合体（RSC）编码了特定试验中假设的方向，而海马旁回位置区（PPA）包含有关JRD起始位置的信息。这些结果表明，在RSC、ERC和PPA中存在视觉引导导航和空间意象共有的空间表征。
