Smith Ikuko T, Townsend Leah B, Huh Ruth, Zhu Hongtu, Smith Spencer L
Neuroscience Center and the Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA.
Neurobiology Curriculum, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA.
Nat Neurosci. 2017 Feb;20(2):200-208. doi: 10.1038/nn.4469. Epub 2017 Jan 9.
Multiple cortical areas contribute to visual processing in mice. However, the functional organization and development of higher visual areas are unclear. Here we used intrinsic signal optical imaging and two-photon calcium imaging to map visual responses in adult and developing mice. We found that visually driven activity was well correlated among higher visual areas within two distinct subnetworks resembling the dorsal and ventral visual streams. Visual response magnitude in dorsal stream areas slowly increased over the first 2 weeks of visual experience. By contrast, ventral stream areas exhibited strong responses shortly after eye opening. Neurons in a dorsal stream area showed little change in their tuning sharpness to oriented gratings while those in a ventral stream area increased stimulus selectivity and expanded their receptive fields significantly. Together, these findings provide a functional basis for grouping subnetworks of mouse visual areas and revealed stream differences in the development of receptive field properties.
多个皮质区域参与小鼠的视觉处理。然而，高级视觉区域的功能组织和发育尚不清楚。在这里，我们使用内在信号光学成像和双光子钙成像来绘制成年和发育中小鼠的视觉反应图谱。我们发现，在两个不同的子网络内的高级视觉区域之间，视觉驱动的活动具有良好的相关性，这两个子网络类似于背侧和腹侧视觉通路。背侧视觉通路区域的视觉反应幅度在视觉体验的前两周缓慢增加。相比之下，腹侧视觉通路区域在睁眼后不久就表现出强烈的反应。背侧视觉通路区域的神经元对定向光栅的调谐锐度变化很小，而腹侧视觉通路区域的神经元则显著提高了刺激选择性并扩大了其感受野。这些发现共同为小鼠视觉区域子网络的分组提供了功能基础，并揭示了感受野特性发育中的通路差异。
