Raz J, Cardenas V, Fletcher D
Department of Biostatistics, School of Public Health, University of Michigan, Ann Arbor 48109-2029, USA.
Biometrics. 1995 Jun;51(2):448-60.
An evoked potential is the recorded brain electrical response to a stimulus such as an auditory click. In most evoked potential experiments, the response is studied as a function of covariates such as stimulus characteristics and drug states. We propose a frequency domain model of multichannel evoked potential data that includes parameters representing the effects of covariates on the amplitude and latency (time from stimulus presentation) of the response. The variability of the response among scalp electrodes is modeled by the activity of one or more equivalent electrical dipoles. The frequency domain representation allows considerable data reduction, facilitates modeling of the noise, and leads to a simple approximate expression for the latency effects. We describe maximum likelihood estimation of the model parameters and construction of approximate confidence intervals for the covariate effects. We report the results of a simulation study in which we evaluated the bias of the estimators and the coverage rate of the confidence intervals. We also report the results of an application to auditory evoked potentials recorded from five subjects.
诱发电位是记录到的大脑对诸如听觉咔嗒声等刺激的电反应。在大多数诱发电位实验中，该反应作为诸如刺激特征和药物状态等协变量的函数进行研究。我们提出了一种多通道诱发电位数据的频域模型，该模型包含表示协变量对反应的幅度和潜伏期（从刺激呈现开始的时间）影响的参数。头皮电极间反应的变异性通过一个或多个等效电偶极的活动进行建模。频域表示允许大量的数据简化，便于对噪声进行建模，并得出潜伏期效应的简单近似表达式。我们描述了模型参数的最大似然估计以及协变量效应近似置信区间的构建。我们报告了一项模拟研究的结果，在该研究中我们评估了估计量的偏差和置信区间的覆盖率。我们还报告了对五名受试者记录的听觉诱发电位进行应用的结果。
