NEUROPHYSIOLOGY OF VISION

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 视觉神经科学的一个中心目标是了解神经活动如何产生知觉体验。色觉是实现这一目标的首要平台。在色觉中，感知的特征特征可以完全由外周受体的众所周知的特性来解释。我们对色觉系统输出和输入的深刻理解，与我们对介于两者之间的神经机制知之甚少形成鲜明对比；大脑皮层的颜色处理仍然知之甚少。 为了发现初级视觉皮质对颜色视觉的贡献，我们记录了观看计算机显示器的动物的单个神经元。我们通过呈现随机产生的彩色图案的快速序列来描述我们研究的每个神经元。偶然的是，这些模式中的一些会刺激神经元，通过专门分析这些模式，我们获得了关于该神经元在处理视觉信息中所扮演的角色的有价值的信息。这一特征还允许我们为探测这种处理的感知结果的行为任务配置显示器。在一项任务中，我们同时探测神经元和动物对微弱颜色光的敏感度。这项实验的结果告诉我们，哪些神经元对调节色觉足够敏感，以及它们的信号必须如何汇集以支持颜色检测。在另一项任务中，我们测量了背景颜色对神经元和动物对颜色相似性判断的影响。实验结果表明，颜色视觉中的空间对比度效应是由初级视觉皮层水平的加工所调节的，还是视觉系统更高水平加工的结果。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. A central goal of visual neuroscience is to understand how neural activity gives rise to perceptual experience. Color vision is a premier platform for achieving this goal. In color vision, well-characterized aspects of perception can be accounted for completely by well-understood properties of the peripheral receptors. Our deep understanding of the output and input of the color vision system stands in stark contrast to how little we know about the neural machinery in between; color processing in the cerebral cortex is still poorly understood. To discover the contribution that the primary visual cortex makes to color vision, we record from single neurons in animals viewing a computer monitor. We characterize each neuron that we study by presenting a rapid sequence of randomly generated colorful patterns. By chance, some of these patterns excite the neuron, and by analyzing these patterns exclusively, we gain valuable information about the role of that neuron plays in processing visual information. This characterization also allows us to configure the display for behavioral tasks that probe the perceptual consequences of this processing. In one task, we simultaneously probe the sensitivity of the neuron and animal to faint colored lights. Results from this experiment tell us which neurons are sufficiently sensitive to mediate color vision and how their signals must be pooled to support color detection. In another task, we measure the effect of background color on the neurons and on the animal's judgments of color similarity. Results from this experiment indicate whether spatial contrast effects in color vision are mediated by processing at the level of primary visual cortex, or are the result of processing at higher levels of the visual system.