牛蛙视网膜神经节细胞的时空相关放电模式

发布时间：2018-04-14 15:31

本文选题：视网膜 + 神经节细胞　；参考：《上海交通大学》2011年硕士论文

【摘要】：视觉信号的初级处理发生在视网膜,视觉信号在视网膜光感受器细胞上形成输入,并将其转化为电信号,经视网膜神经元回路传递至输出神经节细胞,形成动作电位,再通过视神经进一步向视中枢传递。视网膜需要编码的视觉信息通常比较复杂,同时在处理视觉信息时要受到视觉神经通路的解剖结构、以及神经回路中各种噪声的影响。在这些限制下,时空相关编码模式被认为是视网膜的一种高效处理视觉信息的方法。本文对多电极记录到的特定光刺激下牛蛙视网膜神经节细胞放电活动进行了研究,探讨了时空相关编码的特性。主要结果包括两部分:(1)基于信息熵理论,估算了神经元放电序列的时间相关性指标;同时计算了神经元活动的空间相关性指标。分析表明,对于单个神经元而言,时间相关性指标与空间相关性指标是相互关联的:时间相关性指标大的神经元,其空间相关性指标也比较大。而且,进一步研究发现簇状放电(动作电位间隔(inter-spike-interval,ISI)小于6 ms)在神经元的时空相关放电模式中起着重要的作用:神经元的簇状放电越多,放电序列的时间相关性与空间相关性都越强。模型分析表明,时空相关性有助于更精确地预测神经元的放电活动。(2)分析了不同类型放电活动的空间相关特性。将神经元的放电活动分为不同类型:类簇状放电(动作电位间隔小于等于30 ms),单次放电(动作电位间隔大于30 ms)。分析发现,类簇状放电事件的空间相关性要强于单次放电事件的空间相关性,同时与其他神经元形成相关活动的类簇状放电事件所编码的感受野要小于与其他神经元形成相关活动的单次放电所编码的感受野,这表明相关的类簇状放电活动编码了更细节的空间信息。从上述结果可以看出,时空相关模式有利于视网膜高效处理视觉信息,簇状放电在调节视网膜时空反应模式时起着重要的作用。
[Abstract]:The primary processing of visual signal takes place in the retina. The visual signal forms input on the photoreceptor cells of the retina and converts it into electrical signal, which is transmitted to the output ganglion cells through the retinal neuron circuit to form the action potential.Further transmission through the optic nerve to the optic center.The visual information which the retina needs to encode is usually complicated and is affected by the anatomical structure of the visual nerve pathway and various noises in the neural circuit.Under these constraints, spatiotemporal correlation coding pattern is considered to be an efficient method for processing visual information in retina.The discharge activity of retinal ganglion cells (RGCs) recorded by multiple electrodes under specific light stimulation in bullfrog was studied and the characteristics of space-time correlation coding were discussed.The main results include two parts: 1) based on the information entropy theory, the temporal correlation index of neuronal discharge sequence and the spatial correlation index of neuronal activity are estimated.The analysis shows that for a single neuron, the temporal correlation index is correlated with the spatial correlation index, and the spatial correlation index of the neuron with high temporal correlation index is also relatively large.Furthermore, it was found that the inter-spike-intervalis-ISI (action potential interval) plays an important role in the space-time related discharge pattern of neurons: the more clusters of neurons discharge,The temporal and spatial correlations of discharge sequences are stronger.The model analysis shows that the spatio-temporal correlation is helpful to predict the firing activity of neurons more accurately.) the spatial correlation characteristics of different types of firing activities are analyzed.The firing activities of neurons are divided into different types: cluster discharge (action potential interval less than or equal to 30 Ms) and single discharge (action potential interval greater than 30 Ms ~ (-1)).It is found that the spatial correlation of cluster-like discharge events is stronger than that of single discharge events.At the same time, the receptive fields encoded by the cluster-like discharge events associated with other neurons were less than those encoded by single discharges associated with other neurons.This indicates that the related cluster-like discharges encode more detailed spatial information.It can be seen from the above results that the spatio-temporal correlation pattern is beneficial to the efficient processing of visual information in the retina and that the cluster discharge plays an important role in regulating the temporal and spatial response of the retina.
【学位授予单位】：上海交通大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：R774

【共引文献】