Receptive Field Mosaics of Midget, Parasol and Small Bi-Stratified Ganglion Cells

描述(申请人提供)：我们研究的长期目标是了解灵长类视网膜发出的视觉信号，并利用这一知识治疗失明。这项拟议工作的目标是了解视网膜主要神经节细胞类型中视觉信号的三个基本方面，这些细胞向大脑中的多个目标传递不同的视觉信号。其具体目的是探索(1)日光视觉的基本信号，即单个视锥的激活，如何通过平行路径传播到不同的神经节细胞类型；(2)在视网膜内回路中执行的非线性视觉计算的空间结构和起源；(3)在神经节细胞中调节视觉信号的多轴突无长突细胞的组织和功能。为了解决这些问题，我们将利用我们独特的从灵长类动物视网膜分离的大规模多电极记录来采集主要5种神经节细胞类型(遮阳伞、侏儒、离开侏儒和小双层神经节细胞)的完整视觉信号，这些细胞总共构成视觉表征的75%。我们还将通过三项新技术扩展这一独特的实验方法：在大范围视网膜上独立刺激每个视锥感光细胞，高级统计分析以揭示单个视锥细胞分辨率下非线性计算的空间结构，以及从几种类型的无长突细胞与神经节细胞同时记录的电子成像。在这项工作完成后，我们希望对视锥信号如何通过平行通路传输，如何在灵长类动物视网膜的平行回路中组合、处理和调制有更深入的了解。

DESCRIPTION (provided by applicant): The long-term objective of our research is to understand visual signaling by the primate retina, and to exploit this knowledge in the treatment of blindness. The goal of the proposed work is to understand three fundamental aspects of visual signaling in the major ganglion cell types of the retina, which convey distinct visual signals to multiple targets in the brain. The specific aims are to explore (1) how the elementary signal for daylight vision, the activation of a single cone, propagates through parallel pathways to the distinct ganglion cell types; (2) the spatial structure and origin of nonlinear visual computations performed in the inner retinal circuitry; (3) the organization and function of polyaxonal amacrine cells which modulate visual signals in ganglion cells. To approach these problems, we will exploit our unique large-scale multi- electrode recordings from isolated primate retina to sample complete visual signals in the major 5 ganglion cell types (ON parasol, OFF parasol, ON midget, OFF midget, and small bistratified), which collectively constitute 75% of the visual representation. We will also extend this unique experimental approach with three novel techniques: independent stimulation of each of the cone photoreceptors over a large region of retina, advanced statistical analysis to uncover the spatial structure of nonlinear computations at the resolution of individual cones, and electrical imaging to record from several types of amacrine cells simultaneously with ganglion cells. At the completion of this work we hope to have a deeper understanding of how cone signals, transmitted through the parallel pathways, are combined, processed and modulated in the parallel circuits of the primate retina.