Receptive field mosaics of midget, parasol, and small bistratified ganglion cells

描述（由申请人提供）：我们研究的长期目标是了解灵长类动物视网膜的视觉信号，并利用这一知识治疗失明。这项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，这些细胞将不同的视觉信号传递给大脑中的多个目标。具体目的是探索(1)日光视觉的基本信号，单个锥体的激活，如何通过平行途径传播到不同的神经节细胞类型；(2)视网膜内回路中非线性视觉计算的空间结构和来源；(3)神经节细胞中调节视觉信号的多轴突无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大规模多电极记录，从分离的灵长类动物视网膜中取样5种主要神经节细胞类型（ON parasol, OFF parasol, ON midget， OFF midget和小双层）的完整视觉信号，它们共同构成75%的视觉表征。我们还将用三种新技术扩展这种独特的实验方法：在视网膜的大区域上独立刺激每个视锥细胞光感受器，先进的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，以及同时记录几种类型的无突细胞和神经节细胞的电成像。在这项工作完成后，我们希望对通过平行通路传输的视锥信号如何在灵长类动物视网膜的平行回路中被组合、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. PUBLIC HEALTH RELEVANCE: The goal of our work is to understand the visual functioning of the retina, by using innovative large-scale and high-resolution experimental approaches to probe the parallel neural circuits that transmit visual signals to different targets in the brain. In the proposed work, we will probe how signals from individual photoreceptor cells flow through retinal circuits, and how neurons in the inner retina modulate the photoreceptor signals for visual function. We expect these studies to significantly advance our understanding of how the retina signals visual information to the brain, contributing to efforts in our lab and others to design advanced retinal prostheses to treat blindness.