VISUAL DEFICITS IN ALZHEIMER'S DISEASE

本项目的长期目标是发现 老年痴呆症患者的部分视觉系统受到影响 疾病（AD）;特别是那些严重和经常致残 视觉感知障碍。 建议调查 通过客观的、非侵入性的测试， AD患者的视觉诱发电位（VEP），以及年龄- 匹配的控制，使用最近开发的计算机生成的视觉 刺激，可以相对分离的几个功能， 视觉中的多个并行处理系统。 具体目标（1）是回答一些关于视觉的问题 一个大的AD患者和对照组的缺陷， 一项正在进行的研究（NIA，1RO1 AG08870，"知觉的神经心理学 失智症中的疾病"）。 使用适当的视觉刺激， 提出从大细胞中引出神经反应， 小细胞通路，"开"和"关"通路，以及侧支通路。 抑制途径;也测试视觉同步 皮层输入到视网膜的明亮闪光刺激。 具体目标（2）是将这些结果与 广泛的生理和行为研究， 对这组AD患者和对照组进行了研究。 具体 将在大细胞/小细胞结果之间进行比较 在这项拟议的研究中获得的，与心理物理的结果， 大细胞/小细胞系统的探针。

The long term objective of this proposed project is to discover which parts of the visual system are affected in patients with Alzheimer's Disease (AD); particularly those with severe and often disabling disturbances of visual perception. It is proposed to investigate the visual system by means of objective, noninvasive testing utilizing Visual Evoked Potentials (VEP) in patients with AD, together with age- matched controls, using recently developed computer generated visual stimuli that can relatively separate the function of several of the underlying multiple parallel processing systems in vision. Specific Aim (1) is to answer a number of questions about the visual deficits of a large cohort of AD patients and controls participating in an ongoing study (NIA, 1RO1 AG08870, "The Neuropsychology of Perceptual Disorders in Dementia"). Using appropriate visual stimuli, it is proposed to elicit neural responses from the magnocellular and parvocellular pathways, the "on" and "off" pathways, and the lateral inhibitory pathways; and to also test the synchronization of visual cortical input to bright flash stimulation of the retina. Specific Aim (2) is to correlate these results with those of the extensive physiological and behavioral studies which will have been performed upon this cohort of AD patients and controls. Specific comparisons will be made between the magnocellular/parvocellular results obtained in this proposed study, with the results of psychophysical probes of the magnocellular/parvocellular systems in the cohort.