CRCNS: Collaborative Research: How is Information Coded in Turtle Visual Cortex?

ghosh, Bijoy KWashington university， crcns：合作研究：信息如何在海龟视觉皮层编码？视觉刺激在淡水龟的视觉皮层中唤起一种活动的传播波。初步研究表明，有关刺激在视觉空间中的位置的信息被编码在这些波的时空动态中。实际上，视觉皮层的动态可能有一个视觉空间的地图。这一假设正在三个实验室的合作努力中进行检验。圣安东尼奥的大卫·森斯曼（David Senseman）正在使用电压敏感染料方法记录视网膜上35个光点产生的光波。这些研究将根据在35个位点重复呈现的刺激来描绘地图的特征。芝加哥的菲利普·乌林斯基（Philip Ulinski）正在开发一种大规模的海龟视觉通路模型。个体视网膜神经节细胞的模型结合了经典的基于过滤器的神经节细胞建模方法和神经节细胞的区隔建模方法。它们被用来构建与35个基因位点相匹配的35块视网膜模型。目前正在进行海龟外侧膝状复合体神经元生物物理学的生理学研究。它们被用来建立外侧膝状复合体的模型，这是模拟视网膜-膝状-皮质通路的最后一步。圣路易斯的Bijoy Ghosh正在开发一种精确的估计技术，可以通过皮质波的动态来估计视觉刺激的位置。这项工作提供了描述波的动态视觉空间的潜在地图所需的数学框架。这项工作意义重大，因为它描述了一种在视觉皮层中编码信息的新方法，这种方法可能适用于哺乳动物和海龟的高级皮层区域。

EIA-0218186Ghosh, Bijoy KWashington UniversityCRCNS: Collaborative Research : How is Information Coded in Turtle Visual Cortex ?Visual stimuli evoke a propagating wave of activity in the visual cortex of freshwater turtles. Preliminary work suggested that information about the position of stimuli in visual space is coded in the spatiotemporal dynamics of these waves. Effectively, there may be a map of visual space to the dynamics of the visual cortex. This hypothesis is being examined in a collaborative effort involving three laboratories. David Senseman in San Antonio is using voltage sensitive dye methods to record the waves produced by presenting spots of light at 35 spots on the retina. These studies will characterize the features of the map based on repeated presentations of stimuli at 35 loci. Philip Ulinski in Chicago is developing a large-scale model of the visual pathway of turtles. Models of individual retinal ganglion cells that combine both classic filter-based approaches to modeling ganglion cells, with compartmental modeling of ganglion cells are being constructed. They are being used to construct 35 patches of a model retina that match the 35 loci. Physiological studies of the biophysics of neurons in the lateral geniculate complex of turtles are being carried out. They are used to develop a model of the lateral geniculate complex, which is the last step in modeling the retino-geniculate-cortical pathway. Bijoy Ghosh in St. Louis is developing refined estimation techniques that allow the position of a visual stimulus to be estimated from the dynamics of the cortical waves. This work is providing the mathematical framework needed to characterize a potential map of visual space to the dynamics of the wave. This work is significant because it is characterizing a novel method of coding information in visual cortex that may apply to higher order cortical areas in mammals, as well as turtles.