Functional organization of visual responses in the octopus optic lobe.
Functional organization of visual responses in the octopus optic lobe.
复制标题
章鱼视叶视觉反应的功能组织。
DOI：
10.1101/2023.02.16.528734
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Niell,CristopherM
中科院分区：
文献类型：
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作者：
Pungor,JuditR;Allen,VAngelique;Songco-Casey,JeremeaO;Niell,CristopherM
头足类动物是高度视觉化的动物，有着照相机般的眼睛，巨大的大脑，以及丰富的视觉引导行为。然而，头足类动物的大脑是独立于其他高度视觉物种（如脊椎动物）的大脑进化的；因此，处理感觉信息的神经回路是完全不同的。它们强大而独特的视觉系统是如何运作的，这在很大程度上是未知的，因为在头足类动物的大脑中没有对视觉反应的直接神经测量。在这项研究中，我们使用双光子钙成像记录了章鱼中央大脑主要视觉处理中心——视叶的视觉诱发反应，以确定视觉场景的基本特征是如何被表征和组织的。我们发现了光（ON）和暗（OFF）刺激的空间定位接受野，这些接受野在视网膜上组织在视叶上，证明了许多物种共享的视觉系统组织的标志。对这些反应的检查揭示了视觉表征在视叶各层的转变，包括OFF通路的出现和尺寸选择性的增加。我们还发现了打开和关闭刺激的空间处理中的不对称性，这表明形式处理的独特电路机制可能已经进化到适合处理水下视觉场景的特定要求。本研究对章鱼视觉系统的神经加工和功能组织提供了新的认识，突出了它们共同的和独特的方面，并为今后研究调解头足类动物视觉加工和行为的神经回路奠定了基础。
Cephalopods are highly visual animals with camera-type eyes, large brains, and a rich repertoire of visually guided behaviors. However, the cephalopod brain evolved independently from those of other highly visual species, such as vertebrates; therefore, the neural circuits that process sensory information are profoundly different. It is largely unknown how their powerful but unique visual system functions, as there have been no direct neural measurements of visual responses in the cephalopod brain. In this study, we used two-photon calcium imaging to record visually evoked responses in the primary visual processing center of the octopus central brain, the optic lobe, to determine how basic features of the visual scene are represented and organized. We found spatially localized receptive fields for light (ON) and dark (OFF) stimuli, which were retinotopically organized across the optic lobe, demonstrating a hallmark of visual system organization shared across many species. An examination of these responses revealed transformations of the visual representation across the layers of the optic lobe, including the emergence of the OFF pathway and increased size selectivity. We also identified asymmetries in the spatial processing of ON and OFF stimuli, which suggest unique circuit mechanisms for form processing that may have evolved to suit the specific demands of processing an underwater visual scene. This study provides insight into the neural processing and functional organization of the octopus visual system, highlighting both shared and unique aspects, and lays a foundation for future studies of the neural circuits that mediate visual processing and behavior in cephalopods.