Holt C E, Harris W A
Department of Biology, University of California San Diego, La Jolla 92093-0322.
J Neurobiol. 1993 Oct;24(10):1400-22. doi: 10.1002/neu.480241011.
Positional identity in the visual system affects the topographic projection of the retina onto its central targets. In this review we discuss gradients and positional information in the retina, when and how they arise, and their functional significance in development. When the axons of retinal ganglion cells leave the eye, they navigate through territory in the central nervous system that is rich in positional information. We review studies that explore the navigational cues that the growth cones of retinal axons use to orient towards their target and organize themselves as they make this journey. Finally, these axons arrive at their central targets and make a precise topographic map of visual space that is crucial for adaptive visual behavior. In the last section of this review, we examine the topographic cues in the tectum, what they are, when, and how they arise, and how retinal axons respond to them. We also touch on the role of neural activity in the refinement of this topography.
视觉系统中的位置身份影响视网膜向其中心靶标的拓扑投射。在本综述中，我们讨论视网膜中的梯度和位置信息、它们何时以及如何产生，以及它们在发育中的功能意义。当视网膜神经节细胞的轴突离开眼睛时，它们在富含位置信息的中枢神经系统区域中导航。我们综述了一些研究，这些研究探索了视网膜轴突的生长锥在向靶标定向并在这一过程中进行自我组织时所使用的导航线索。最后，这些轴突到达它们的中心靶标，并形成视觉空间的精确拓扑图，这对于适应性视觉行为至关重要。在本综述的最后一部分，我们研究了顶盖中的拓扑线索、它们是什么、何时以及如何产生，以及视网膜轴突如何对它们做出反应。我们还探讨了神经活动在这种拓扑结构细化中的作用。
