Asymmetries between achromatic and chromatic extraction of 3D motion signals.
Asymmetries between achromatic and chromatic extraction of 3D motion signals.
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3D 运动信号的消色差和彩色提取之间的不对称。
DOI：
10.1073/pnas.1817202116
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发表时间：
2019
影响因子：
11.1
通讯作者：
Kaestner M
中科院分区：
文献类型：
--
作者：
Kaestner M
深度运动（MID）可以通过双眼视差随时间（CD）的高分辨率变化和低分辨率眼间速度差（IOVD）来提示。这两种机制之间的计算差异表明，它们可以在具有不同空间和时间分辨率的视觉通路中实现。在这里，我们使用功能磁共振成像来研究如何无色和S-锥信号有助于人类MID的看法。CD和IOVD刺激在广泛的网络中引起反应，该网络包括早期视觉区域、背侧流和腹侧流的部分以及运动选择性区域hMT+。然而，至关重要的是，我们测量了MID类型和色度之间的相互作用。fMRI CD反应主要由无色刺激驱动，但IOVD反应更好地由等亮度S锥输入驱动。在我们的心理物理学实验中，当S-锥和无色刺激相匹配的感知对比度，参与者同样敏感的MID在无色和S-锥IOVD刺激。相比之下，它们对S-锥CD相对不敏感。这些发现提供了证据，MID机制不对称地利用信息在皮层前通路。由S锥通路最佳地传达的早期对手运动信号可以为IOVD机制提供实质性贡献。
Motion in depth (MID) can be cued by high-resolution changes in binocular disparity over time (CD), and low-resolution interocular velocity differences (IOVD). Computational differences between these two mechanisms suggest that they may be implemented in visual pathways with different spatial and temporal resolutions. Here, we used fMRI to examine how achromatic and S-cone signals contribute to human MID perception. Both CD and IOVD stimuli evoked responses in a widespread network that included early visual areas, parts of the dorsal and ventral streams, and motion-selective area hMT+. Crucially, however, we measured an interaction between MID type and chromaticity. fMRI CD responses were largely driven by achromatic stimuli, but IOVD responses were better driven by isoluminant S-cone inputs. In our psychophysical experiments, when S-cone and achromatic stimuli were matched for perceived contrast, participants were equally sensitive to the MID in achromatic and S-cone IOVD stimuli. In comparison, they were relatively insensitive to S-cone CD. These findings provide evidence that MID mechanisms asymmetrically draw on information in precortical pathways. An early opponent motion signal optimally conveyed by the S-cone pathway may provide a substantial contribution to the IOVD mechanism.