Mechanisms and plasticity of long term visual adaptation to ocular optics

长期视觉适应眼光学的机制和可塑性

• 批准号: 8668060
• 负责人: GEUNYOUNG YOON
• 金额: $ 37.61万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-02 至 2017-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8668060
• 关键词: Address; Adult; Adverse effects; Affect; Blindness; Classification; Complement; Complex; Contrast Sensitivity; Cornea; Corneal Diseases; Data; Defect; Discrimination; Eye; Frequencies; Gases; Goals; Human; Image; Judgment; Keratoconus; Letters; Long-Term Effects; Measurement; Measures; Methodology; Methods; Modeling; Neuronal Plasticity; Noise; Optics; Patients; Pattern; Perception; Perceptual Masking; Performance; Phase; Play; Population; Process; Property; Psychophysics; Regimen; Research; Retina; Retinal; Role; Stimulus; System; Testing; Time; Training; Vision; Visual; Visual Acuity; Visual system structure; Work; adaptive optics; base; design; experience; image processing; improved; innovation; insight; lens; luminance; monocular; neuroadaptation; novel; public health relevance; relating to nervous system; research study; response; spatial vision; theories; tool; visual adaptation; visual deprivation; visual optics; visual performance; visual process; visual processing; visual stimulus

DESCRIPTION (provided by applicant): In eyes with prolonged visual deprivation induced by the abnormally large optical defects such as aberrations, the actual visual performance after precise correction of remaining aberrations is significantly poorer than that predicted from optical theory and that measured in normal eyes. This unexplained vision loss suggests that the degraded image quality received by the eyes alters neural processing of images formed on the retina, which plays an important role in determining perceived visual quality. We hypothesize that the post-correction functional measurements on a given patient are biased by long-term neural adaptation to the poor retinal image quality that the patient may have progressively experienced before correction. We will test this hypothesis using a corneal disease, keratoconus as a model of long-term visual adaptation. The visual system of this unique patient group developed normally but, during adulthood, has gradually experienced severely degraded image quality by the large magnitude of aberrations for a prolonged period of time. The proposed project implements the latest tools and advances in human optics research to investigate (1) the mechanisms underlying long-term neural adaptation to degraded optical quality of the eye and (2) neural plasticity resulting from improved optics and/or visual training paradigms. We will use two innovative advanced correction tools: an adaptive optics vision simulator and a customized scleral lens for short-term and long-term precise aberration correction, respectively. Aim 1 is designed to investigate the mechanisms that underlie long-term neural adaptation to the optically degraded retinal image quality and their impact on neural processing of image quality by (1.1) testing the hypothesis that the neural system is capable to compensate for losses in image quality due to the ocular aberration through long-term adaptation to phase spectra using broadband stimuli, acuity letters and natural images (1.2) characterizing long-term adaptation induced-changes in the key properties of basic spatial vision mechanisms using narrow band visual stimuli i.e. gratings and (1.3) examining the effects of long-term neural adaptation on the two eyes being integrated with regard to the monocular functions including visual acuity, contrast perception at and above threshold before and after aberration correction. Aim 2 will assess the extent to which plasticity that occurs during long-term adaptation is reversible and what mechanistic changes underlie this reversal once aberration-free image quality is achieved in KC eyes. (2.1) We will first quantify the time course of "passive" neural re-adaptation to improved ocular optics achieved by wearing customized aberration correcting scleral lens daily. We will also apply different visual training paradigms based on (2.2) narrow (single spatial frequency gratings) and (2.3) broad (natural images) band visual stimuli to differentiate different mechanisms of neural plasticity and to test the hypothesis that visual performance can further be improved by the visual training. Binocular transfer of the monocular neural manipulation through visual training effects will also be examined.

描述(申请人提供)：对于因异常大的光学缺陷(如像差)而导致长时间视觉剥夺的眼睛，精确矫正剩余像差后的实际视觉表现明显低于光学理论预测和正常眼的测量结果。这种无法解释的视力损失表明，眼睛接收到的图像质量下降，改变了视网膜上形成的图像的神经处理，这在决定感知的视觉质量方面发挥着重要作用。我们假设，对特定患者的矫正后功能测量是有偏差的，因为患者在矫正前可能已经逐渐经历了糟糕的视网膜图像质量的长期神经适应。我们将使用一种角膜疾病圆锥角膜作为长期视觉适应的模型来检验这一假设。这一独特的患者组的视觉系统发育正常，但在成年后，由于长时间的大范围像差，图像质量逐渐严重下降。拟议的项目采用了人类光学研究中的最新工具和进展，以调查(1)长期神经适应眼睛光学质量下降的机制，以及(2)由于改进的光学和/或视觉训练范例而导致的神经可塑性。我们将使用两种创新的先进矫正工具：自适应光学视觉模拟器和定制的巩膜透镜，分别用于短期和长期的精确像差矫正。目的1旨在研究长期神经适应光学退化的视网膜图像质量的机制及其对图像质量的神经处理的影响，通过(1.1)测试神经系统能够通过使用宽带刺激长期适应于相位谱来补偿由于眼睛像差造成的图像质量损失的假设，视力字母和自然图像(1.2)表征长期适应诱导的基本空间视觉机制的关键属性的变化使用窄带视觉刺激，即光栅和(1.3)检查长期神经适应对被整合的双眼的影响，包括单眼功能，包括像差矫正前后的视力、阈值和阈值以上的对比度感觉。目标2将评估在长期适应过程中发生的可塑性的可逆程度，以及一旦KC眼获得无像差的图像质量，这种可逆的机制变化是什么。(2.1)我们将首先量化每天配戴定制的矫正像差巩膜镜片所实现的“被动”神经对改善的眼科光学的再适应的时间进程。我们还将应用基于(2.2)窄(单一空间频率栅格)和(2.3)宽带(自然图像)视觉刺激的不同视觉训练范例来区分不同的 神经可塑性的机制，并验证视觉训练可以进一步提高视觉表现的假设。还将考察通过视觉训练效果进行的单眼神经操作的双眼转移。