HIGH SPATIAL FREQUENCY FEATURE ACUITY IN AMBLYOPIA

弱视的高空间频率特征敏锐度

• 批准号: 3259263
• 负责人: STANLEY A KLEIN
• 金额: $ 11.68万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-07-01 至 1992-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3259263
• 关键词: amblyopia; eye coordination disorder; human subject; neural information processing; psychophysics; sequential perception; stimulus /response; vision tests; visual feedback; visual perception; visual photosensitivity; visual stimulus; visual threshold

The most frequent cause of visual loss in childhood is functional amblyopia. Recent studies show that a high spatial frequencies and under conditions of crowding, qualitatively different acuity losses are found in different amblyopes. The present proposal will capitalize on these differences as a means of clarifying the specific losses in peripheral vision and amblyopic vision compared to normal foveal vision. Just as color deficient individuals had contributed much to our knowledge of color vision, we expect amblyopes will contribute much to our knowledge of spatial vision. Several new psychophysics methodologies will be used to help unravel the comples story: 1. There is a golden opportunity to learn about the amblyopic distortion by comparing the amblyopic eye to the nonamblyopic eye. Under the proper conditions, amblyopes (even those with anomalous correspondence) can not determine the eye-of-origin of a stimulus. By using a double judgment methodology, eye-of-origin confusions will be used to convert subjective interocular comparisons into objective signal detection measurements. New methods for analyzing double judgment tasks with the effects of response bias and response correlation minimized will be used to extend signal detection methodology to the suprathreshold regime. The proposed experiments will focus upon the interactions between local features in peripheral as well as amblyopic vision: 1-Repetitive arrays of features will allow apatial frequency analysis to be used. Spatial frequencies within 3/2 octave of the cutoff spatial frequency will be exhaustively investigated. Effects of phase and background contrast will be explored. 2-A hierarchy of localized luminance distributions will be used to measure contrast sensitivity and phase sensitivity will be studied in amblyopes and peripheral vision. 3. After the first year, nonlocal phase effects, effects of crowding and two dimensional stimuli (ie vernier acuity) will be studies. 4. Quantitative modelling will be used to explain amblyopic and peripheral losses in terms of underlying mechanisms.

儿童期视觉丧失最常见的原因是功能 弱视。 最近的研究表明，高空间频率及以下 拥挤的条件，质量不同的敏锐度损失在 不同的弱视。 目前的提议将利用这些建议 差异作为阐明周围特定损失的一种手段 视力和弱视视力与正常的凹觉视力相比。 就像 颜色不足的人为我们的颜色知识做出了很大的贡献 远见，我们希望弱势群体会为我们的知识做出很大的贡献 空间视觉。 将使用几种新的心理物理学方法来帮助解开 情节：1。有一个千载难逢的机会来了解 通过将弱点眼与非宾夕法尼亚的弱点进行比较，弱视失真 眼睛。 在适当的条件下，弱视（即使是异常的人 对应性）无法确定刺激的原始眼睛。 经过 使用双重判断方法，将使用原始的混乱 将主观的眼上比较转换为客观信号 检测测量。分析双重判断任务的新方法 随着响应偏差和响应相关的影响，将 被用来将信号检测方法扩展到上方的状态。 提出的实验将集中于本地之间的相互作用 外围和弱视视觉中的特征：1-重复阵列 功能将允许使用临时频率分析。 空间 截止空间频率的3/2八度范围内的频率将是 详尽的调查。 相位和背景对比的影响将 被探索。 2-局部亮度分布的层次结构将是 用于测量对比度灵敏度和相位灵敏度 在弱视和外围视力中。 3。第一年之后，非本地 相位效应，拥挤的影响和二维刺激（即Vernier 敏锐度）是研究。 4。定量建模将用于解释 在基本机制方面，弱视和外围损失。