COLOR AND LUMINANCE INTERACTIONS IN VISUAL CORTEX

视觉皮层中颜色和亮度的相互作用

• 批准号: 6012768
• 负责人: ELIZABETH N JOHNSON
• 金额: $ 1.82万
• 依托单位: NEW YORK UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-09-02 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6012768
• 关键词: Macaca fascicularis; behavioral /social science research tag; brightness discrimination; cell type; color visions; electrodes; electroencephalography; histology; lateral geniculate body; neural information processing; oscillography; space perception; visual cortex; visual feedback; visual perception; visual stimulus; visual threshold

DESCRIPTION Most objects in the normal visual environment vary in luminance and chromaticity, and are rarely differentiated solely by either brightness or color. Psychophysical studies using the simultaneously presentation of color-varying and luminance-varying stimuli indicate that there is a wide range of non-linear color-luminance interactions, but the nature and extent of chromatic and luminance interactions in early visual cortex remains unclear. The proposed experiments aim to determine whether these interactions occur in single neurons in the primary visual cortex (V1) of anesthetized, paralyzed macaque monkeys. The monkeys will be presented with drifting gratings containing a super-position of equiluminant color and luminance. The contrasts of the chromatic and the luminance components are varied independently, allowing for a complete parametric analysis of the effects of a broad range of chromatic and luminance contrasts. Spatial features, such as waveform, spatial frequency, and relative phase will be varied. This range of stimuli closely resembles the stimuli used in the psychophysical studies. It will therefore bee possible to determine whether responses as early as V1 show the same strong non-linear effects observed psychophysically. Control experiments in the lateral geniculate nucleus will verify the range of interactions that originate in V1. Histological reconstruction of each electrode penetration will allow cells to be classified according to their anatomical organization to determine trends among cells linked to the processing of color and luminance within the known V1 network hierarchy. Discerning the mechanisms involved in normal early cortical processing of color and luminance will enable us to correlate neurophysiological responses to perception. In addition, it will allow for a better understanding of the chromatic and spatial vision deficits facing many patients with cortical damage, aiding the development of better diagnostic tests for such visual deficits.

描述正常视觉环境中的大多数物体在亮度和色度上都有变化，很少单独通过亮度或颜色来区分。心理物理学研究同时呈现的颜色变化和亮度变化的刺激表明，有一个广泛的非线性颜色-亮度的相互作用，但在早期视觉皮层的色彩和亮度的相互作用的性质和程度仍然不清楚。拟议的实验旨在确定这些相互作用是否发生在麻醉，瘫痪猕猴的初级视觉皮层（V1）的单个神经元中。将向猴提供含有等亮度颜色和亮度叠加的漂移光栅。色彩和亮度分量的对比度独立变化，允许对广泛的色彩和亮度对比度的影响进行完整的参数分析。诸如波形、空间频率和相对相位的空间特征将变化。这种刺激范围与心理物理学研究中使用的刺激非常相似。因此，有可能确定早在V1时的反应是否表现出与精神病理学观察到的相同的强非线性效应。在外侧膝状体核的控制实验将验证起源于V1的相互作用的范围。每个电极穿透的组织学重建将允许根据细胞的解剖组织对细胞进行分类，以确定与已知V1网络层级内的颜色和亮度处理相关的细胞之间的趋势。辨别正常的早期皮层处理颜色和亮度的机制将使我们能够将神经生理反应与感知联系起来。此外，它将允许更好地了解许多皮质损伤患者面临的彩色和空间视觉缺陷，帮助开发更好的诊断测试。