Comparison of amplitude estimates in the single trial estimation of evoked potentials

A method for the single trial estimation of the evoked potentials is presented. The method is based on the regularized least squares scheme. An approach to single trial estimation of multi channel evoked potentials is derived by applying additional information of the spatial correlation of the channels to the estimation. Amplitude estimates obtained with these methods are compared. The performance of the methods is evaluated using real data of target responses in the P300 test. The multi channel approach is shown to give realistic and comparable information about the amplitude differences of the P300 peak between different channels. Keywords— Evoked potentials, single trial estimation, multi channel, regularization