INFORMATION TRANSFER AND CONTRAST SENSITIVITY

信息传输和对比度灵敏度

• 批准号: 3259484
• 负责人: EHUD KAPLAN
• 金额: $ 20.25万
• 依托单位: ROCKEFELLER UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1984
• 资助国家: 美国
• 起止时间: 1984-09-01 至 1992-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3259484
• 关键词: Macaca; binocular vision; cats; cell type; color visions; corticofugal system; electrophysiology; interneurons; lateral geniculate body; luminescence; neural information processing; neural transmission; psychophysics; retina; retinal ganglion; sequential perception; single cell analysis; stimulus /response; visual feedback; visual perception; visual photosensitivity; visual stimulus

This proposal aims at a better understanding of the functional organization of the central visual pathways of mammals, and attempts to relate visual functions to neuronal populations in the primate. I will focus on two main problems: 1) What are the dynamic properties of the contrast gain control we recently discovered in the Lateral Geniculate Nucleus (LGN)? and 2) What is the neural substrate for the psychophysically determined luminance and color contrast sensitivities? The first question stems from the observations that the LGN is a dynamic filter of the incoming retinal information, and that its filtering (attenuation) of retinal input increases with stimulus contrast. This observation lead to a set of new experiments, in which the contrast of a pattern is modulated in time. I will record in anesthized and paralyzed cats and monkeys the responses of single LGN cells together with their retinal input (recorded as synaptic (S) potentials), and measure the time course with which the LGN adjusts its transmission ratio (LGN response/retinal response) following a step increase in contrast. The importance of temporal and spatial stimulus parameters, as well as that of retinal eccentricity and binocular interactions, will all be explored. The second question is stimulated by the observation that in the monkey LGN the parvocellular neuons (and their drives, the P cells) are much less sensitive to luminance contrast than the magnocellular neurons (or the retinal M cells), and by recent psychophysical work (Mullen, 1985) which compared the contrast sensitivity for color and luminance patterns in humans. I will establish which neuronal population could account for these results by measruing the responses of single P and M cells in the monkey LGN to both luminance and chromatic patterns. I will also measure the sensitivities of the receptor field center and periphery to luminance and color modulations, to uncover the reason for the unbounded increase in response to color stimuli with stimulus size, noted in the P cells, and the source of the difference in contrast gain between M and P cells. The results will shed light on the function of the M cells and P cells in primate vision.

该建议旨在更好地理解功能 哺乳动物的中心视觉途径的组织 尝试将视觉功能与神经元种群相关联 灵长类动物。 我将专注于两个主要问题：1） 对比增益控制的动态特性我们最近 在侧向元音核（LGN）中发现？ 2）什么 是心理物理确定的神经底物 亮度和颜色对比度敏感性？ 第一个问题源于观察到LGN是一个 传入的视网膜信息的动态过滤器，并 视网膜输入的过滤（衰减）随着刺激的增加而增加 对比。 该观察结果导致一组新实验， 图案的对比是在时间上调制的。 我会 记录在麻醉和瘫痪的猫和猴子中 单个LGN细胞及其视网膜输入的响应 （记录为突触电位），并测量时间过程 LGN调整其传输比（LGN） 反应/视网膜反应）在对比度增加后。 时间和空间刺激参数的重要性， 以及视网膜偏心率和双眼相互作用的 全部探索。 第二个问题是通过观察到的 猴子lgn the parvocellular neuons（及其驱动器，p 细胞）对亮度对比的敏感性要比 巨细胞神经元（或视网膜M细胞），并且最近 心理物理工作（Mullen，1985），比较对比 人类对颜色和亮度模式的敏感性。 我会 确定哪些神经元人口可以考虑这些 通过测量单个P和M细胞在 猴子的亮度和色差。 我会 还测量受体场中心的敏感性和 亮度和颜色调制的外围，以发现 响应颜色刺激的无限增加的原因 具有刺激大小，在P细胞中注明，是 M和P细胞之间的对比增益差异。 结果 会阐明M细胞和P细胞在中的功能 灵长类动物的视野。