The Emergence of Tuning to Global Shape Properties of Radial Frequency Patterns in the Ventral Visual Pathway.
The Emergence of Tuning to Global Shape Properties of Radial Frequency Patterns in the Ventral Visual Pathway.
复制标题
腹侧视觉通路中径向频率模式的整体形状特性调整的出现。
DOI：
10.1523/jneurosci.2237-22.2023
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发表时间：
2023-07-19
影响因子：
5.3
通讯作者：
Morland, Antony B.
中科院分区：
文献类型：
--
作者：
Lawrence, Samuel J. D.;Zamboni, Elisa;Vernon, Richard J. W.;Gouws, Andre D.;Wade, Alex R.;Morland, Antony B.
径向频率（RF）模式，由圆半径的正弦调制产生，在RF低时进行全局处理。因此，这些封闭的形状为询问人类视觉系统对曲率的全局处理提供了一种有用的方法。射频模式引起的反应比V4的径向光栅和腹侧视觉通路中更多的前脸选择区域更大。这在很大程度上与对非人类灵长类动物的研究一致，研究表明，弯曲处理出现在V4，但也明显出现在腹侧视觉流的上方。我们没有将射频模式与其他刺激进行对比，而是在一种方案中以不同的频率呈现它们，该方案允许从8名人类参与者（3名女性）获得射频调谐。我们发现在枕侧区域和V4区域有一定程度的低射频调谐。在对照实验中，我们在刺激中加入高频纹波，破坏局部轮廓。对这些刺激的低频调谐仍然存在于腹侧视觉流中，强调了其在形状曲率的整体加工中的作用。然后，我们使用表征相似性分析来表明，在侧枕区，神经表征与刺激相似性有关，当它被一个捕捉到如何感知刺激的模型计算时。因此，我们发现，形状曲率的整体处理早在V4就出现在腹侧视觉流中，但在枕侧区域发现得更强烈，枕侧区域表现出与感知相关的反应和表征。我们表明，调谐到低径向频率，已知参与整体形状处理机制，是定位于外侧枕区。当考虑到低水平刺激特性时，除了对象选择区域LO之外，V4和LO2也出现了这种调谐。我们还记录了枕侧区域整体形状属性的表征，这些表征可以通过刺激之间的感知差异来很好地预测。
Radial frequency (RF) patterns, created by sinusoidal modulations of a circle's radius, are processed globally when RF is low. These closed shapes therefore offer a useful way to interrogate the human visual system for global processing of curvature. RF patterns elicit greater responses than those to radial gratings in V4 and more anterior face-selective regions of the ventral visual pathway. This is largely consistent with work on nonhuman primates showing curvature processing emerges in V4, but is evident also higher up the ventral visual stream. Rather than contrasting RF patterns with other stimuli, we presented them at varied frequencies in a regimen that allowed tunings to RF to be derived from 8 human participants (3 female). We found tuning to low RF in lateral occipital areas and to some extent in V4. In a control experiment, we added a high-frequency ripple to the stimuli disrupting the local contour. Low-frequency tuning to these stimuli remained in the ventral visual stream, underscoring its role in global processing of shape curvature. We then used representational similarity analysis to show that, in lateral occipital areas, the neural representation was related to stimulus similarity, when it was computed with a model that captured how stimuli are perceived. We therefore show that global processing of shape curvature emerges in the ventral visual stream as early as V4, but is found more strongly in lateral occipital regions, which exhibit responses and representations that relate well to perception. SIGNIFICANCE STATEMENT We show that tuning to low radial frequencies, known to engage global shape processing mechanisms, was localized to lateral occipital regions. When low-level stimulus properties were accounted for such tuning emerged in V4 and LO2 in addition to the object-selective region LO. We also documented representations of global shape properties in lateral occipital regions, and these representations were predicted well by a proxy of the perceptual difference between the stimuli.