Tracking the emergence of location-based spatial representations in human scene-selective cortex
Tracking the emergence of location-based spatial representations in human scene-selective cortex
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跟踪人类场景选择皮层中基于位置的空间表征的出现
DOI：
10.1101/547976
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Berens S
中科院分区：
文献类型：
--
作者：
Berens S
人脑的场景选择区域形成了我们环境中位置的异中心表征。这些表示与前进方向无关，使我们无论行进方向如何都知道自己在哪里。然而，我们对这些基于位置的表示是如何形成的知之甚少。使用功能磁共振成像表征相似性分析和线性混合模型，我们追踪了场景选择性大脑区域中基于位置的表征的出现。我们估计了参与者得知自己来自同一地点之前和之后拍摄的两个不同场景的活动模式。在学习阶段，我们向参与者提供了两种类型的全景视频：(1) 重叠视频条件，显示来自同一位置的两个不同场景（0° 和 180°）；(2) 无重叠视频，显示来自不同位置的两个不同场景（作为控制条件）。在海马旁皮层（PHC）和压后皮层（RSC）中，来自同一位置的场景的表征只有在重叠条件下显示后才变得更加相似，这表明独立于视点的基于位置的表征的出现。尽管这些表征出现在 PHC 中，而与任务表现无关，但 RSC 表征仅出现在参与者可以行为地将两个场景识别为属于同一位置的位置。结果表明，我们可以在单个 fMRI 实验中追踪 PHC 和 RSC 中基于位置的表示的出现。此外，他们支持的计算模型表明 RSC 在将独立于观点的表示转换为特定观点的行为相关表示方面发挥着关键作用。
Scene-selective regions of the human brain form allocentric representations of locations in our environment. These representations are independent of heading direction and allow us to know where we are regardless of our direction of travel. However, we know little about how these location-based representations are formed. Using fMRI representational similarity analysis and linear mixed models, we tracked the emergence of location-based representations in scene-selective brain regions. We estimated patterns of activity for two distinct scenes, taken before and after participants learnt they were from the same location. During a learning phase, we presented participants with two types of panoramic videos: (1) an overlap video condition displaying two distinct scenes (0° and 180°) from the same location and (2) a no-overlap video displaying two distinct scenes from different locations (which served as a control condition). In the parahippocampal cortex (PHC) and retrosplenial cortex (RSC), representations of scenes from the same location became more similar to each other only after they had been shown in the overlap condition, suggesting the emergence of viewpoint-independent location-based representations. Whereas these representations emerged in the PHC regardless of task performance, RSC representations only emerged for locations where participants could behaviorally identify the two scenes as belonging to the same location. The results suggest that we can track the emergence of location-based representations in the PHC and RSC in a single fMRI experiment. Further, they support computational models that propose the RSC plays a key role in transforming viewpoint-independent representations into behaviorally relevant representations of specific viewpoints.