Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA.
Neural Comput. 2011 Nov;23(11):2731-45. doi: 10.1162/NECO_a_00198. Epub 2011 Aug 18.
Characterizing neural spiking activity as a function of intrinsic and extrinsic factors is important in neuroscience. Point process models are valuable for capturing such information; however, the process of fully applying these models is not always obvious. A complete model application has four broad steps: specification of the model, estimation of model parameters given observed data, verification of the model using goodness of fit, and characterization of the model using confidence bounds. Of these steps, only the first three have been applied widely in the literature, suggesting the need to dedicate a discussion to how the time-rescaling theorem, in combination with parametric bootstrap sampling, can be generally used to compute confidence bounds of point process models. In our first example, we use a generalized linear model of spiking propensity to demonstrate that confidence bounds derived from bootstrap simulations are consistent with those computed from closed-form analytic solutions. In our second example, we consider an adaptive point process model of hippocampal place field plasticity for which no analytical confidence bounds can be derived. We demonstrate how to simulate bootstrap samples from adaptive point process models, how to use these samples to generate confidence bounds, and how to statistically test the hypothesis that neural representations at two time points are significantly different. These examples have been designed as useful guides for performing scientific inference based on point process models.
将神经尖峰活动作为内在和外在因素的函数进行描述在神经科学中很重要。点过程模型对于捕捉此类信息非常有价值;然而,全面应用这些模型的过程并不总是显而易见的。完整的模型应用有四个广泛的步骤:模型的规范、给定观测数据的模型参数估计、使用拟合优度验证模型以及使用置信区间来描述模型。在这些步骤中,只有前三个在文献中得到了广泛应用,这表明需要专门讨论时间缩放定理如何与参数引导抽样相结合,以便一般用于计算点过程模型的置信区间。在我们的第一个例子中,我们使用尖峰倾向的广义线性模型来证明,从引导模拟中得出的置信区间与从闭式解析解中计算出的置信区间一致。在我们的第二个例子中,我们考虑了一个没有分析置信区间的海马体位置场可塑性的自适应点过程模型。我们展示了如何从自适应点过程模型中模拟引导样本,如何使用这些样本生成置信区间,以及如何统计检验两个时间点的神经表示是否有显著差异的假设。这些例子旨在为基于点过程模型进行科学推理提供有用的指南。