An Information-Driven 2-Pathway Characterization of Occipitotemporal and Posterior Parietal Visual Object Representations
An Information-Driven 2-Pathway Characterization of Occipitotemporal and Posterior Parietal Visual Object Representations
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DOI：
10.1093/cercor/bhy080
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发表时间：
2019-05-01
期刊：
影响因子：
3.7
通讯作者：
Xu, Yaoda
中科院分区：
文献类型：
--
作者：
Vaziri-Pashkam, Maryam;Xu, Yaoda
近年来的研究表明，枕颞叶皮层（OTC）和后顶叶皮层（PPC）都存在丰富的视觉表征。使用功能磁共振成像解码和自下而上的数据驱动的方法，我们发现，虽然强大的对象类别的表征存在于OTC和PPC，有一个信息驱动的2-通路分离这些区域之间的代表性空间，与枕颞区层次安排沿着1通路和后顶叶区域沿着另一条通路。我们获得了10个独立的重复这2-通路的区别，占58-81%的视觉表示的区域差异的总方差。PPC地区的分离，从更高的枕颞区的差异，在低层次的视觉功能的变化的容忍度，不依赖于特殊的对象类别的存在，并存在是否对象类别是任务相关的。我们的信息驱动的2-通路结构不同于众所周知的腹侧-什么和背侧-哪里/如何表征后脑区域。这两种途径都包含丰富的非空间视觉表征。我们看到的分离可能反映了PPC与OTC相比，用于表示视觉信息的神经编码方案的差异。
Recent studies have demonstrated the existence of rich visual representations in both occipitotemporal cortex (OTC) and posterior parietal cortex (PPC). Using fMRI decoding and a bottom-up data-driven approach, we showed that although robust object category representations exist in both OTC and PPC, there is an information-driven 2-pathway separation among these regions in the representational space, with occipitotemporal regions arranging hierarchically along 1 pathway and posterior parietal regions along another pathway. We obtained 10 independent replications of this 2-pathway distinction, accounting for 58-81% of the total variance of the region-wise differences in visual representation. The separation of the PPC regions from higher occipitotemporal regions was not driven by a difference in tolerance to changes in low-level visual features, did not rely on the presence of special object categories, and was present whether or not object category was task relevant. Our information-driven 2-pathway structure differs from the well-known ventral-what and dorsal-where/how characterization of posterior brain regions. Here both pathways contain rich nonspatial visual representations. The separation we see likely reflects a difference in neural coding scheme used by PPC to represent visual information compared with that of OTC.