STRUCTURAL BASIS OF AMBLYOPIA & STRABISMUS

弱视的结构基础

• 批准号: 6116725
• 负责人: JONATHON C HORTON
• 金额: $ 4.41万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-05-01 至 2000-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6116725
• 关键词: Mammalia

Significance Strabismus (also known colloquially as "crossed eyes") affects visual function in 2% of the American population. Our research is directed at elucidating the structural changes in the primate visual cortex, which occurs, from strabismus. Objectives In primate striate cortex, geniculocortical afferents in layer IVc terminate in parallel stripes called ocular dominance. This segregation of ocular inputs generates a related but distinct columnar system of monocular core zones alternating with binocular border strips. Evidence for this functional parcellation was obtained by comparing the effects of enucleation, eyelid suture, and retinal laser lesions on cytochrome oxidase (CO) activity in 8 macaques. Our goal was to learn how binocular, stereo-sensitive cells are organized in the visual cortex. Results Enucleation produced a high-contrast pattern of dark and light columns in layer IVc, corresponding precisely to the ocular dominance columns, whereas eyelid suture produced a low-contrast pattern of thin dark columns alternating with wide pale columns. [3H]proline eye injection showed that the thin dark columns corresponded to the core zones of the open eye's ocular dominance columns. The wide pale columns resulted from loss of CO activity in the sutured eye's core zones and within both eyes' border strips. Loss of CO activity within both eyes' border strips suggests that these regions are binocular. TO confirm our findings, we compared different CO patterns in the same cortex by making retinal laser lesions in 4 animals. They produced a CO pattern tantamount to "focal" enucleation, although contrast was low when laser damage was confined to the outer retina. CO levels in cortical scotomas remained severely depressed for months after retinal lesions, even when the other eye was enucleated. This observation provided little anatomical support for the notion to topographic plasticity after visual deafferentation. In a single human subject with macular degeneration, CO revealed a low-contrast pattern of ocular dominance columns, resembling the pattern in monkeys with laser-induced photoreceptor damage. Future Directions Analysis of the changes in metabolic activity, which occur in ocular dominance columns as a result of visual suppression, induced by strabismus. KEY WORDS strabismus, visual cortex, ocular dominance FUNDING National Eye Institute, RO1 EY 10217-06 PUBLICATIONS Horton, J.C., and Hocking, D.R., Monocular Core Zones and Binocular Border Strips in Primate Striate Cortex Revealed by the Contrasting Effects of Enucleation, EyelidSuture, and Retinal Laser Lesions Upon Cytochrome Oxidase Activity. Journal of Neuroscience,18:5433-5455,1998.

显着性斜视（也称为“交叉” 眼睛”）影响2％的美国人口的视觉功能。 研究旨在阐明 来自斜视的灵长类动物视觉皮层。 目标中 灵长类动物皮质，IVC层中的基因皮层传入 在称为眼优势的平行条纹中终止。 这 眼部输入的分离产生相关但不同的柱子 单眼核心区的系统与双眼边界交替 条。 通过 比较壳核，眼睑缝合和视网膜激光的影响 8猕猴中细胞色素氧化酶（CO）活性的病变。 我们的目标 是为了了解如何在 视觉皮层。 结果摘除产生了高对比度 IVC层中的深色和光柱的模式，相应 恰恰是眼睛优势柱，而眼睑缝合线 产生了与薄深色柱的低对比度图案交替 宽阔的圆柱。 [3H]脯氨酸注射显示薄 深色柱与睁大眼眼的眼部的核心区域相对应 优势柱。 宽阔的圆柱是由CO的丢失而产生的 在缝合眼的核心区域和双眼边框中的活动 条。 两只眼睛边界条内的CO活动损失表明 这些区域是双眼的。 为了确认我们的发现，我们 通过进行视网膜来比较同一皮质中的不同CO模式 4只动物中的激光病变。 他们产生了一个CO模式的触角 “焦点”摘除，尽管当激光损伤为时对比度很低 局限于视网膜外。 皮质Scotomas中的CO水平仍然存在 视网膜病变后几个月严重抑郁，即使 另一只眼睛被摘除。 这种观察几乎没有解剖学 在视觉后支持对地形可塑性的概念 停用。 在具有黄斑变性的单一人类受试者中 CO揭示了眼部优势柱的低对比度模式， 类似于用激光诱导的光感受器在猴子中的图案 损害。 代谢变化的未来方向分析 活动，这是由于眼部优势柱的发生 视觉抑制，由斜视诱导。 关键词斜视， 视觉皮层，眼部优势资助国家眼科研究所，RO1 EY 10217-06 Publications Horton，J.C。和Hocking，D.R。，单眼核心 灵长类横向皮层中的区域和双眼边界条揭示了 通过壳核，眼睑和视网膜的对比效果 激光病变在细胞色素氧化酶活性上。 杂志 神经科学，18：5433-5455,1998。