The large-scale organization of shape processing in the ventral and dorsal pathways: Subject 160927143355_Experiment 2

160927143355 nii files. Part of
a dataset from the paper entitled : The large-scale organization of shape
processing in the ventral and dorsal pathways by Freud, Culham, Plaut and Behrmann.
See - https://doi.org/10.1184/R1/c.3889873.v1. For each participant 8
functional runs and one anatomical run are included.

Abstract:Although shape perception is considered a
function of the ventral visual pathway, evidence suggests that the dorsal
pathway also derives shape-based representations. In two psychophysics and
neuroimaging experiments, we characterized the response properties, topographical organization
and perceptual relevance of these representations. In both pathways, shape
sensitivity increased from early visual cortex to extrastriate cortex but then
decreased in anterior regions. Moreover, the lateral aspect of the ventral
pathway and posterior regions of the dorsal pathway were sensitive to the
availability of fundamental shape properties, even for unrecognizable images.
This apparent representational similarity between the posterior-dorsal and
lateral-ventral regions was corroborated by a multivariate analysis. Finally, as
with ventral pathway, the activation profile of posterior dorsal regions was
correlated with recognition performance, suggesting a possible contribution to
perception. These findings challenge a strict functional dichotomy between the
pathways and suggest a more distributed model of shape processing.

160927143355 个 NII 文件，是论文《腹侧和背侧通路中形状处理的大规模组织》的一部分，该论文由 Freud、Culham、Plaut 和 Behrmann 撰写。详见 - https://doi.org/10.1184/R1/c.3889873.v1。对于每位参与者，包含 8 次功能性扫描和 1 次解剖学扫描。

摘要：尽管形状感知被视为腹侧视觉通路的功能，但证据表明背侧通路亦能产生基于形状的表征。在两项心理物理学和神经影像学实验中，我们描述了这些表征的响应特性、拓扑组织和感知相关性。在两条通路中，形状敏感性从早期视觉皮层增加到超皮层，但在前部区域有所下降。此外，腹侧通路的侧部和背侧通路的后部区域对基本形状属性的可获得性敏感，即使对于难以识别的图像也是如此。后背侧和侧腹侧区域之间这种明显的表征相似性得到了多元分析的支持。最后，与腹侧通路类似，后背侧区域的激活模式与识别性能相关，这表明其可能对感知有所贡献。这些发现挑战了通路之间的严格功能二分法，并提出了一种更分布式的形状处理模型。