Statistics of the maintained discharge of cat retinal ganglion cells.
Statistics of the maintained discharge of cat retinal ganglion cells.
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猫视网膜神经节细胞维持放电的统计。
DOI：
10.1113/jphysiol.1983.sp014728
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
Levine,MW
中科院分区：
文献类型：
--
作者：
Frishman,LJ;Levine,MW
记录麻醉猫视束中的单纤维的动作电位。在不同水平的暗视和中间视觉视网膜照明下获得连续记录。在某些情况下，光强度由伪随机高斯白噪声信号调制。随着感受野中心照明的增加，中心神经元的维持放电增加，而偏离中心神经元的维持放电减少。对于两种电池类型，变异系数随着放电速率的增加而下降。放电模式的短期依赖性最小，并且不受视网膜照明水平的影响。事实上，归一化自协方差函数揭示的所有结构都可以归因于区间分布的形状。序列相关图的前几个系数略为负。这种负面影响的大小与照明无关。射击模式的长期依赖性也很小；大约 1 秒持续时间的样本中平均速率的标准偏差仅略小于根据间隔分布预测的值。这种依赖性在视网膜照明较高时趋于增加。光的高斯调制引起的神经放电与稳定光引起的神经放电明显不同。调制导致串行相关图的第一个系数变得更加正，而接下来的几个系数变得更加负。在归一化自协方差函数以及归一化自协方差和归一化自卷积之间的差异中可以看到相应的模式。长期依赖性也急剧增加，因此平均率的标准差约为观察到的区间分布的预期值的 60%。这些结果对视网膜中的固有噪声进入视觉处理网络的方式施加了许多限制。提出了两种与数据一致的替代模型。
Action potentials were recorded from single fibres in the optic tracts of anaesthetized cats. Continuous records were obtained at various levels of scotopic and mesopic retinal illumination. In some cases, the light intensity was modulated by a pseudorandom Gaussian white‐noise signal. The maintained discharge of on‐centre neurones increased while the maintained discharge of off‐centre neurons decreased with increased illumination of the receptive field centre. For both cell types, the coefficient of variation declined with increased rate of discharge. There was minimal short‐term dependency in the firing patterns, and it was unaffected by the level of retinal illumination. Virtually all of the structure revealed by the normalized autocovariance functions could be attributed to the shape of the interval distributions. The first few coefficients of the serial correlogram were slightly negative. The magnitude of this negativity was not related to illumination. Long‐term dependency in the firing pattern was also quite small; the standard deviations of the mean rate in samples of about 1 sec duration were only slightly less than would be predicted from the interval distributions. This dependency tended to increase at higher retinal illuminations. Neural discharges elicited by Gaussian modulation of the light were strikingly different from those elicited by steady light. Modulation caused the first coefficient of the serial correlogram to become more positive, while the next several coefficients became more negative. A corresponding pattern could be seen in the normalized autocovariance functions, and in the differences between the normalized autocovariance and normalized autoconvolution. Long‐term dependency also increased dramatically, such that the standard deviations of mean rate were about 60% of what would be expected given the interval distributions observed. These results place a number of constraints upon the ways in which intrinsic noise in the retina may enter the visual processing network. Two alternative models consistent with the data are presented.