The structure of brain regions is assumed to correlate with their function, but there are very few instances in which the relationship has been demonstrated in the live brain. This is due to the difficulty of simultaneously measuring functional and structural properties of brain areas, particularly at cellular resolution. Here, we performed label-free, third-harmonic generation (THG) microscopy to obtain a key structural signature of cortical areas, their effective attenuation lengths (EAL), in the vertical columns of functionally defined primary visual cortex and five adjacent visual areas in awake mice. EALs measured by THG microscopy in the cortex and white matter showed remarkable correspondence with the functional retinotopic sign map of each area. Structural features such as cytoarchitecture, myeloarchitecture and blood vessel architecture were correlated with areal EAL values, suggesting that EAL is a function of these structural features as an optical property of these areas. These results demonstrate for the first time a strong relationship between structural substrates of visual cortical areas and their functional representation maps in vivo. This study may also help in understanding the coupling between structure and function in other animal models as well as in humans.

中文翻译：

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小鼠视觉皮层区域的三次谐波定量成像揭示了功能图与结构底物之间的相关性

假定大脑区域的结构与其功能相关，但是在活脑中几乎没有这种关系的实例。这是由于很难同时测量大脑区域的功能和结构特性，尤其是在细胞分辨率下。在这里，我们进行了无标签的第三谐波产生（THG）显微镜检查，以获取功能区定义的主要视觉皮层和五个相邻视觉区域的垂直列中皮质区域的关键结构特征，其有效衰减长度（EAL）。清醒的老鼠。通过THG显微镜在皮层和白质中测得的EALs与每个区域的功能性视网膜位点标志图显着对应。结构特征，例如细胞结构，骨髓结构和血管结构与面积的EAL值相关，这表明EAL是这些结构特征随这些区域的光学性质而变的函数。这些结果首次证明了视觉皮层区域的结构底物与其体内功能代表图之间的密切关系。这项研究也可能有助于理解其他动物模型以及人类中结构与功能之间的耦合。