Adapting-bump model for eccentric cells of Limulus.
Adapting-bump model for eccentric cells of Limulus.
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DOI：
10.1085/jgp.76.5.539
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发表时间：
1980-11
期刊：
影响因子：
--
通讯作者：
Knight BW
中科院分区：
文献类型：
--
作者：
Wong F;Knight BW
光诱发的细胞内电压噪声记录已从鲎偏心细胞获得，从阈值光强度到10（5）倍阈值的强度。这些数据进行了分析，在一个简单的“自适应凹凸”噪声模型。它示出了该模型如何产生一个数据减少的过程，稍微概括了熟悉的使用坎贝尔定理泊松散粒噪声：自适应的相关效应修正坎贝尔定理由一个单一的乘法因子，这可能是直接从噪声数据的功率谱估计。该模型还允许从功率谱直接估计凸块形状。在昏暗的光线下从噪声估计的凸块形状与在黑暗中直接观察到的凸块的平均形状非常一致。该数据产生的碰撞率在约50倍阈值强度内与光呈线性，但在最亮的光下，其线性度下降福尔斯35倍。凸起高度在整个范围内随着光强度的-0.4次方而减小。碰撞持续时间在整个范围内减少了2倍，自适应相关因子从1下降到约三分之一。适度的变化的适应相关性表明，天真的应用程序的坎贝尔的定理，这样的数据是足够的模型的生理参数的粗略估计。这种对所有数据的简单解释支持自适应凹凸模型。
Light-evoked intracellular voltage noise records have been obtained from Limulus eccentric cells, from threshold light intensity to an intensity .10(5) times threshold. These data are analyzed in terms of a simple "adapting-bump" noise model. It is shown how the model yields a data reduction procedure that slightly generalizes the familiar use of Campbell's theorem for Poisson shot noise: the correlative effect of adaptation amends Campbell's theorem by a single multiplicative factor, which may be estimated directly from the power spectrum of the noise data. The model also permits direct estimation of the bump shape from the power spectrum. The bump shape estimated from noise at dim light is in excellent agreement with the average shape of bumps observed directly in the dark. The data yield a bump rate that is linear with light up through about 50 times threshold intensity but that falls short of linearity by a factor of 35 at the brightest light. The bump height decreases as the -0.4 power of light intensity across the entire range. Bump duration decreases by a factor of 2 across the entire range, and the adaptation correlation factor descends from unity to about one-third. The modest change of the adaptation correlation shows that naive application of Campbell's theorem to such data is adequate for rough estimation of the model's physiological parameters. This simple accounting for all the data gives support to the adapting-bump model.