Role of Vision in Etiology of Axial Myopia

描述（由申请人提供）：越来越多的人认为近视不是一种疾病，而是一种对眼睛生长指导的监管失败。所研究的儿童和大多数动物的眼睛天生近视或远视（远视），并在出生后调整其生长以矫正视力（远视）。很明显，动物的这种调整过程是在视觉控制下进行的：让动物戴上正镜片或负镜片都会迅速补偿离焦，使眼睛恢复到以前的屈光状态。理解眼向化需要弄清楚眼睛如何区分聚焦在视网膜后面的图像（这需要眼睛增加其伸长的速度）和聚焦在视网膜前面的图像（这需要眼睛减缓其伸长的速度），以及视网膜中的信息如何转化为调节眼睛生长的信号。关于第一个问题，有证据表明，眼睛利用蓝光聚焦在红光前面的事实（纵向色差）来引导其生长。实验提出，以测试眼睛是否可以转移到或远离近视通过操纵刺激的色度特性。关于第二个问题，当眼睛暴露在相反方向的离焦环境中时，两个分子信号会朝着相反的方向变化，这表明它们可能是连接视网膜视觉信号和眼睛生长控制机制的信号级联的一部分。在鸟类和哺乳动物身上进行实验，以发现决定眼睛是否补偿晶状体的晶状体佩戴时间的特定条件是否也决定了这些分子信号是否在适当的方向上改变以控制代偿性眼睛生长。因为控制离焦如何导致补偿性眼睛生长的规则在许多不同的物种中似乎是相似的，似乎同样的过程也在人类身上起作用。由于近视是一种普遍存在的疾病，似乎与视觉体验，特别是阅读有关，因此了解这些视觉介导的生长控制过程是如何工作的很重要。这些知识为我们提供了最好的机会来了解是什么使一些儿童患上近视。

DESCRIPTION (provided by applicant): It is becoming increasingly accepted that myopia is not a disease but a regulatory failure of the guidance of eye-growth. The eyes of children and most animals studied are born myopic or hyperopic (far-sighted) and adjust their growth during the postnatal period to correct their vision (emmetropization). It is clear that in animals this adjustment process is under visual control: Having animals wear positive or negative spectacle lenses causes a rapid compensation for the defocus, returning the eye to its previous refractive state. Understanding emmetropization requires finding out both how the eye can distinguish an image focused in back of the retina (which requires the eye to increase its rate of elongation) from an image focused in front of the retina (which requires the eye to slow its elongation) and how this information in the retina gets transformed into a signal that modulates eye-growth. With respect to the first problem, there is evidence that the eye uses the fact that blue light is focused in front of red light (longitudinal chromatic aberration) to guide its growth. Experiments are proposed to test whether the eye can be shifted toward or away from myopia by manipulations of the chromatic properties of stimuli. With respect to the second problem, two molecular signals change in opposite directions when the eye is exposed to opposite directions of defocus, suggesting that they might be part of the signal cascade that connects the visual signal in the retina to the growth-controlling machinery of the eye. Experiments are proposed in both birds and mammals to discover whether the particular conditions of timing of lens-wear that determine whether or not the eye compensates for lenses also determine whether or not these molecular signals change in the appropriate direction to be controlling the compensatory eye growth. Because the rules controlling how defocus leads to compensatory eye-growth appear to be similar across many different species, it seems likely that the same processes are at work in humans. Because myopia is a widespread condition that seems associated with visual experience, especially reading, it is important to understand how these visually mediated growth control processes work. Such knowledge provides our best opportunity to understand what makes some children develop myopia.