弱视患者立体视功能损伤的机制研究及可能恢复途径探索

Stereopsis is of functional significance to human being. Impaired stereopsis, which is one of the most common deficits associated with amblyopia, adversely affects the life quality of patients with amblyopia. Literature review in amblyopia showed the lack of understanding of the mechanisms of the stereopsis deficits in amblyopia. .Recently, we developed a multi-pathway contrast-gain control model (MCM), which could explain excellently the behavioral data measured in both binocular contrast perception and disparity threshold from normal people. The MCM is a powerful framework and suitable to be used in studying the mechanisms of stereopsis deficits in amblyopia..In this proposal, we systematically measure the disparity threshold under different contrast, spatial and temporal frequencies and extend the current MCM to account for the data of both normal and amblyopic people. With the extended MCM, we could quantitatively characterize the stereopsis deficits in amblyopia with three system parameters. Also we train the amblyopic participants with several perceptual learning paradigms, and examine the outcomes as well as the system parameters before and after training. These data would lead to a deeper understanding of the mechanisms of stereopsis deficits in amblyopia and have potential value for the recovery of stereovision in amblyopia.

立体视功能损伤是弱视患者的主要表现之一，对其日常生活有显著影响。弱视立体视功能损伤的认知神经机制尚不清楚，成人弱视患者立体视功能的恢复也是临床难题之一。对弱视立体视功能损伤和恢复机制的研究有着重大的理论和实际意义。本项目拟以申请人在近期工作中提出的立体视对比度增益控制模型为切入点，系统深入地研究弱视患者立体视功能损伤特性，并揭示其神经机制。同时通过横向比较几种立体视恢复方法对成人弱视患者立体视的改善程度，找到恢复成人弱视患者立体视功能的最有效的方法。

立体视功能损伤是弱视患者的主要表现之一，严重影响患者生活质量。弱视立体视功能损伤的认知神经机制尚不清楚，成人弱视患者立体视功能的恢复也是临床难题之一。对弱视立体视功能损伤和恢复机制的研究有着重大的理论和实际意义。本项目以负责人在前期工作中提出的多通路对比度增益控制模型为切入点，系统地测量了弱视患者的一系列视觉功能，包括弱视眼、相对健眼、以及双眼对比敏感度随空间频率变化的函数、弱视患者两眼视觉功能损伤的动态特性，以及弱视患者的立体视定位能力。我们发现，弱视患者的双眼对比敏感度和立体视锐度与正常对照相比有显著下降，其空间定位强烈依赖于相对健眼，这些视觉功能异常可能同时由弱视眼对输入的信号衰减和弱视眼受到相对健眼的较强抑制所导致，同时，弱视眼和相对健眼的视觉信息处理时间窗口形状未见显著差异，验证了申请人提出的“衰减—抑制共同作用”假说。本项目加深了人们对立体视觉系统的处理机制的理解。项目开展过程中，针对传统视觉功能测试方法的不足，我们开发了一套全新的单、双眼视觉功能的定量化智能评估方法，具有潜在的应用前景。整个项目基本上按照计划执行，项目经费基本使用完毕，目前项目相关的主体工作已经完成，已达到项目预计目标。