The large-scale organization of shape processing in the ventral and dorsal pathways: Subject 160920121024_Experiment 2

160920121024 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.

160920121024 nii 文件。该数据集来自名为《腹侧和背侧通路中形状处理的大规模组织》的论文，作者为 Freud、Culham、Plaut 和 Behrmann。参见 - https://doi.org/10.1184/R1/c.3889873.v1。对于每一位参与者，包含8次功能性扫描和1次解剖学扫描。

摘要：尽管形状感知被认为属于腹侧视觉通路的功能，但证据表明背侧通路同样产生了基于形状的表征。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额外的纹状皮层，但在前部区域随后降低。此外，腹侧通路的侧面和背侧通路的后部区域对基本形状属性的存在敏感，即使对于不可识别的图像也是如此。这种后背侧和侧腹侧区域之间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，背侧区域激活模式与识别性能相关，这表明它们可能对感知有贡献。这些发现挑战了通路之间严格的功能二分法，并暗示了形状处理的一个更加分布化的模型。