A new view on post-receptoral signal processing in retino-geniculate pathways of humans.

在第一个资助期内进行的研究结果表明，视网膜电图（ERG）可以反映不同感光细胞类型和主要的后感受器（微小和大细胞; ON和OFF）视网膜通路的活动。此外，这些视网膜通路的时间，光谱和空间特性进行了研究。这是第一次在人类受试者体内研究视网膜的生理学，与视觉感知相关。这些数据导致了以下问题，将在应用项目中进行研究：该项目的一个重要目标是使用新方法来研究起源于不同感光细胞类型和主要postreceptoral途径的信号。新的刺激（时间白色噪声; TWN）和分析（互相关）技术将被开发和使用来一个更完整的描述在视网膜的视觉信息处理。TWN刺激技术非常适合独立研究平均亮度和刺激强度的影响。该方法也可以很容易地与所谓的沉默替代刺激相结合，利用沉默替代刺激可以刺激单个感光器类型。本课题的第二个目标是通过在不同视网膜位置使用小刺激和使用多焦刺激来扩展光感受器驱动和通路反射ERG的空间测量。这些实验将阐明起源于不同光感受器和不同视网膜通路的信号的空间分布。这项工作最终将导致视网膜的功能图像。最终的目标将集中在是否锥分布和视网膜回路在所有灵长类动物中通常是相同的问题上。因此，计划在休斯顿大学（美国）Laura Frishman教授的实验室对非人类灵长类动物进行ERG实验。ON-和OFF-途径的贡献将通过使用这些途径的选择性阻断进行研究。

The results of the research performed in the frame of the first funding period showed that the electroretinogram (ERG) can reflect activity of the different photoreceptor types and of the major postreceptoral (parvo- and magnocellular; ON- and OFF-) retinal pathways. In addition, temporal, spectral and spatial properties of these retinal pathways were studied. For the first time, it was possible to study the physiology of the retina, with a relevance for visual perception, in vivo in human subjects.These data led to the following issues that will be studied in the applied project:An important goal of the project will be to use novel methods to study the signals that originate in the different photoreceptor types and in the major postreceptoral pathways. Novel stimulation (temporal white noise; TWN) and analysis (cross-correlation) techniques will developed and used to come a more complete description of the visual information processing in the retina. The TWN stimulation technique is extremely well suited to study the effects of mean luminance and stimulus intensity independently. The method can also easily be combined with the so-called silent substitution stimulation, with which single photoreceptor types can be stimulated. Neither the independent studies nor the combination with silent substitution is possible with the conventional ERG techniques.A second goal of the project is to extend the spatial measurements of the photoreceptor driven and pathway reflecting ERGs by using small stimuli at different retinal locations and by using multifocal stimulation. These experiments will elucidate the spatial distribution of the signals originating in the different photoreceptors and in the different retinal pathways. This work should ultimately lead to a functional image of the retina.A final goal will concentrate upon the question if cone distribution and retinal circuitries are generally the same in all primates. Therefore ERG experiments on non-human primates, in the laboratory of Prof. Laura Frishman at the University of Houston (USA), are planned. The contributions of ON- and OFF-pathways will be studied by using selective blockades of these pathways.