Signal Processing in the Inner Retina

描述（由申请人提供）：哺乳动物视网膜含有至少15-20种类型的视网膜神经节细胞，每种细胞被调节以最好地响应视觉场景中的不同且有时复杂的特征。 总之，这些不同的神经节细胞反应为我们提供了我们用来在视觉世界中导航的所有信息。 每种类型的视网膜神经节细胞都通过收集突触前神经元的信息来监测视网膜表面的一个小块，即它的感受野。 双极细胞和无长突细胞，分别有12种和30多种。虽然有助于神经节细胞光反应的无长突和双极细胞连接的一般模式是已知的，但IPL的令人生畏的复杂性阻碍了我们对区分IPL的调谐特性的特定连接的理解。 神经节细胞类型。 我们已经开发了一个光遗传学和基于病毒的技术工具箱，这将使我们能够跟踪和功能特征的双极，无长突和神经节细胞之间的连接杆占主导地位的小鼠和锥占主导地位的地松鼠视网膜。 在三个具体的目标，我们的目标是：1）测试的假设，神经节细胞获得不同的时间光响应，部分地，通过总结双极细胞的兴奋性输入与不同的时间响应。2)测试神经节细胞从具有不同时间特性的不同类型的无长突细胞获得直接输入的假设， 3)确定在促肾上腺皮质激素释放激素（CRH）启动子控制下表达cre重组酶的特定无长突细胞类型的功能连接和视觉作用。 我们的工作将定义特定内部视网膜回路的布线和功能，并为理解已知的回路变化提供背景。 光感受器变性后发生，无论是遗传性或年龄发作性疾病。

DESCRIPTION (provided by applicant): The mammalian retina contains at least 15-20 types of retinal ganglion cells each tuned to respond best to different and sometimes complex features in a visual scene. Together, these diverse ganglion cell responses provide us with all of the information that we use to navigate in the visual world. Each type of retinal ganglion cell monitors a patch on the retinal surface, its receptive field, by collecting inputs from presynaptic bipolar and amacrine cells of which there are more than 12 and 30 types, respectively. While the general patterns of amacrine and bipolar cell connectivity that contribute to he ganglion cell light response are known, the daunting complexity of the IPL has impeded our understanding of the specific connections that underlie the tuning properties that distinguish the ganglion cell types. We have developed a toolbox of optogenetic and virally-based techniques that will enable us to trace and functionally characterize the connections between bipolar, amacrine, and ganglion cells in both the rod dominant mouse and cone dominant ground squirrel retinas. In three specific aims, our goals are to: 1) test the hypothesis that ganglio cells obtain different temporal light responses, in part, by summing the excitatory inputs of bipolar cells with different temporal responses. 2) test the hypothesis that ganglion cells obtain direct input from different types of amacrine cells with different temporal properties and, 3) determine the functional connections and the role in vision of a specific amacrine cell type that expresses cre recombinase under the control of the corticotropin releasing hormone (CRH) promoter. Our work will define the wiring and functions of specific inner retinal circuits i health, and provide the background for understanding circuit changes that are known to occur following photoreceptor degeneration, whether from genetic or age-onset disease.