Functional connectivity in primary visual cortex

项目摘要 所有能在视网膜上形成图像的动物，从苍蝇到人类，都需要打开和关闭大脑通路， 处理视觉场景中的明暗特征。传统的教科书观点认为，这些ON和OFF 通路在视觉皮层完全会聚，使神经元对刺激方向具有选择性，但对 刺激极性和空间相位。与这种传统观点相反，我们最近的工作表明，ON和OFF 视皮层中的通路分离，专门负责不同的时空功能并处理图像 彼此相对独立。此外，我们的初步结果表明，ON和OFF皮质 通路对亮度范围变化的反应非常不同，亮度范围在我们的视觉中不断变化， 环境从日出到日落。基于我们的研究结果，我们假设亮度感知起源于 从两个单独的和相对独立的ON和OFF通路之间的相互作用， 与自然场景中明暗特征的统计数据相匹配。这种对ON和OFF的新理解 大脑皮层加工对人类亮度感知、图像脑加工分析具有重要意义 并且可以帮助改进可用于管理人类视觉疾病治疗的诊断工具。在这 建议，我们将研究如何打开和关闭皮层通路相互作用，以产生亮度感知， 这些相互作用如何随背景亮度、亮度范围和视杆/视锥视网膜比率而变化 对图像进行采样。然后，我们将使用所有这些测量来开发复制人类的模型， 亮度感知比过去更准确，新的诊断工具可以测量人类的ON， 在影响视网膜（如青光眼）和视皮层（如弱视）的疾病中关闭视觉功能。

PROJECT SUMMARY All animals that can form images in their retinas, from flies to humans, need ON and OFF brain pathways to process light and dark features in visual scenes. The traditional textbook view is that these ON and OFF pathways fully converge in visual cortex to make neurons selective to stimulus orientation but invariant to stimulus polarity and spatial phase. Against this traditional view, our recent work demonstrates that ON and OFF pathways segregate in visual cortex, specialize in different spatiotemporal functions, and process images relatively independently from each other. In addition, our preliminary results indicate that ON and OFF cortical pathways respond very differently to changes in luminance range, which varies continuously in our visual environment from sunrise to sunset. Based on our results, we hypothesize that luminance perception originates from the interaction between two separate and relatively independent ON and OFF pathways that are exquisitely matched to the statistics of light and dark features in natural scenes. This new understanding of ON and OFF cortical processing has important implications for human luminance perception, image brain processing analysis and could help improve the diagnostic tools available to manage treatment in human visual disease. In this proposal, we will investigate how ON and OFF cortical pathways interact to generate luminance perception, and how these interactions vary with background luminance, luminance range and the rod/cone retinal ratio available to sample the images. We will then use all these measurements to develop models that replicate human luminance perception more accurately than in the past and new diagnostic tools that measure human ON and OFF visual function in diseases that affect the retina (e.g. glaucoma) and visual cortex (e.g. amblyopia).