APPLICATION OF PSYCHOPHYSICAL MODELS TO VISUAL DISORDERS

描述(摘自)：这项研究的长期目标是 视力障碍患者的功能缺陷与潜在因素的关系 细胞病理生理学。更好地理解这些关系 将在治疗试验的设计中有用，在选择试验中 对个别患者的评估，并在指导生物分子和 生理学研究。研究采用量化模型，严谨严谨 心理物理方法，以及精心挑选的患者群体 调查功能缺陷和生物损伤之间的联系。 建议的研究集中在神经节细胞的心理物理测量上。 相对暗点(敏感度降低的局部区域)中的函数 患有进展性疾病的患者，这些疾病主要只损害一类 神经元：视网膜神经节细胞(青光眼)或光感受器(视网膜炎) 着色性)。对于这两种疾病，都有关于细胞作用的争论。 损害，以及细胞死亡的机制。具体目标有三个： 1)模拟神经节细胞损伤对视野阈值的影响。和 将这些模型应用于患者数据。定性模型已经被 建议用视网膜神经节细胞来解释相对暗点 损害，但还没有开发出定量模型。关于人类和人类的数据 猕猴神经节细胞马赛克将用于建立定量模型 将神经节细胞损伤与周界阈值升高联系起来，并应用 这是使用标准视野收集的正常数据和患者数据 刺激和创新刺激。2)研究视觉的可逆性 青光眼引起的缺陷。关于青光眼的缺陷是否 可逆的。离散神经节细胞嵌合体的局部敏感性将是 青光眼患者急性手术前、后的测量 以确定视觉功能是否有所改善。3)至 视网膜炎患者相对暗点的时间加工评价 色素变性(RP)。关于RP的暂时性缺陷是否存在争议 由于锥体敏感度降低(减少的量子捕获量和/或 转导效率)，或者与锥体中的时间处理缺陷或 内层视网膜。时间敏感度将以相对敏感度衡量 RP患者的暗点，在平均视网膜照度允许 视锥细胞敏感度下降与单纯的暂时性视锥细胞损害相区别。

DESCRIPTION (from abstract): The long-term objective of this research is to relate functional deficits in patients with visual disorders to underlying cellular pathophysiology. A better understanding of these relationships will be useful in design of treatment trials, in selecting tests for evaluation of individual patients, and in guiding biomolecular and physiological studies. The research uses quantitative models, rigorous psychophysical methods, and carefully selected patient populations to investigate the linkage between functional defects and biological damage. The proposed research focuses on psychophysical measures of ganglion cell function in relative scotomas (local regions of reduced sensitivity) in patients with progressive diseases which primarily damage only one class of neuron: retinal ganglion cells (glaucoma) or photoreceptors (retinitis pigmentosa). For both diseases, there is debate over the effects of cell damage, and over the mechanisms of cell death. There are 3 specific aims: 1 ) To model effects of ganglion cell damage on perimetric thresholds. and to apply these models to patient data. Qualitative models have been proposed to account for relative scotomas in terms of retinal ganglion cell damage, but quantitative models have not been developed. Data on human and macaque ganglion cell mosaics will be used to build a quantitative model to link ganglion cell damage with perimetric threshold elevations, and apply this to normal and patient data gathered with both standard perimetric stimuli and innovative stimuli. 2) To investigate reversibility of visual deficits caused by glaucoma. It is debated whether glaucomatous defects are reversible. Local sensitivity of discrete ganglion cell mosaics will be measured in patients with glaucoma before and after acute surgical reduction of intraocular pressure to determine if visual function improves. 3) To evaluate temporal processing in relative scotomas of patients with retinitis pigmentosa (RP). There is debate over whether temporal defects in RP are due to reduction in cone sensitivity (reduced quantal catch and/or transduction efficiency), or to a temporal processing defect in the cones or the inner retina. Temporal sensitivity will be measured in relative scotomas of patients with RP, at a mean retinal illuminance which allows cone sensitivity loss to be distinguished from purely temporal.