Center for Visual Science, University of Rochester, Rochester, NY 14620, USA; Department of Ophthalmology, University of Washington, Seattle, WA 98109, USA.
Department of Ophthalmology, University of Washington, Seattle, WA 98109, USA.
Curr Biol. 2022 Jun 6;32(11):2529-2538.e4. doi: 10.1016/j.cub.2022.04.056. Epub 2022 May 18.
The detection of motion direction is a fundamental visual function and a classic model for neural computation. In the non-primate retina, direction selectivity arises in starburst amacrine cell (SAC) dendrites, which provide selective inhibition to direction-selective retinal ganglion cells (dsRGCs). Although SACs are present in primates, their connectivity and the existence of dsRGCs remain open questions. Here, we present a connectomic reconstruction of the primate ON SAC circuit from a serial electron microscopy volume of the macaque central retina. We show that the structural basis for the SACs' ability to confer directional selectivity on postsynaptic neurons is conserved. SACs selectively target a candidate homolog to the mammalian ON-sustained dsRGCs that project to the accessory optic system (AOS) and contribute to gaze-stabilizing reflexes. These results indicate that the capacity to compute motion direction is present in the retina, which is earlier in the primate visual system than classically thought.
运动方向的检测是一种基本的视觉功能，也是神经计算的经典模型。在非灵长类动物的视网膜中，方向选择性出现在星状无长突细胞（SAC）的树突中，这些细胞对方向选择性视网膜神经节细胞（dsRGC）提供选择性抑制。尽管 SAC 存在于灵长类动物中，但它们的连接和 dsRGC 的存在仍然是悬而未决的问题。在这里，我们从猕猴中央视网膜的一系列电子显微镜体积中呈现了灵长类动物 ON SAC 回路的连接组重建。我们表明，SAC 能够为突触后神经元赋予方向选择性的结构基础是保守的。SAC 选择性地针对一种候选的哺乳动物 ON 持续 dsRGC 的同源物，该同源物投射到辅助视觉系统（AOS）并有助于眼球稳定反射。这些结果表明，计算运动方向的能力存在于视网膜中，而在灵长类动物的视觉系统中，这一能力比传统上认为的更早出现。
