EFFECTS OF VIEWING DISTANCE ON EYE GROWTH & REFRACTIVE DEVELOPMENT

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 近视(近视)是一种视力障碍，影响25%的美国人，每年的费用为40亿美元。它最近被美国国立卫生研究院确定为解决健康差距方面的优先事项，因为它可能会对一些少数群体造成不成比例的影响。虽然其病因尚不清楚，但研究表明，遗传和环境因素可能起到了作用。在儿童中，如果父母双方都近视，但其中一人阅读超过平均水平，则患近视的可能性更高。动物模型试图通过强调视网膜图像的质量来识别环境影响的性质，使用形觉剥夺或恒定散焦。本次SCORE项目的主题是观看距离也会影响眼睛的生长和屈光状态。我们的初步研究支持这一断言，接下来我们建议检验以下假设的几个推论：在近距离长时间暴露于视觉刺激足以导致恒河猴眼睛过度伸长和相对近视。目的1.检验视觉任务在近视距离(NVD)下的日常表现会导致近视移位的预测。目的2.检验这样一种假设：在出生后的发育过程中，近视距离的限制足以引起近视的变化。对于所有目标，屈光误差的测量将通过睫状肌麻痹验光获得，眼轴长度的测量将通过A超进行，调节行为的测量将使用红外线(IR)光折射进行。在这些功能关系建立之后，未来的研究将被提出来检验神经机制。长期目标是了解视觉体验、眼睛生长和屈光状态之间的关系，以及指导这些关系的机制。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Myopia (nearsightedness) is a visual disorder that affects 25% of Americans, at a cost of $4 billion/year. It has recently been identified by NIH as a priority to address in terms of health disparities because it can disproportionately affect some minority groups. While its etiology remains unknown, studies suggest a role for genetic and environmental factors. In children, there is a higher likelihood of myopia if both parents are myopic, but also if one reads more than average. Animal models have attempted to identify the nature of the environmental influence by an emphasis on the quality of the retinal image, using form deprivation or constant defocus. The thesis of the present SCORE project is that viewing distance also influences eye growth and refractive status. Our initial studies support this assertion and we next propose to test several corollaries of the following hypothesis: prolonged exposure to visual stimuli at a near viewing distance is sufficient to induce excessive ocular elongation and relative myopia in rhesus monkeys. Aim 1. To test the prediction that daily performance of a visual task at a near viewing distance (NVD) will induce a myopic shift. Aim 2. To test the hypothesis that the restriction of viewing distance to near is sufficient to induce a myopic shift during postnatal development. For all aims, measurements of refractive error will be obtained via cycloplegic retinoscopy, measurements of axial length of the eye will be made via A-scan ultrasound, and measurements of accommodative behavior will be made using infra-red (IR) photorefraction. After these functional relationships are established, future studies will be proposed to examine neural mechanisms. The long-term goal is to understand the relationship between visual experience, eye growth, and refractive status, and the mechanisms that guide those relationships.