Is Wiener Filtering an Effective Method of Improving Evoked Potential Estimation?

In order to obtain better estimates of the true evoked potential signal with fewer stimuli than is possible with classical signal averaging, the Wiener theory [16] for optimum linear filtering, as formulated by Walter [15] and Doyle [5], was implemented in four different versions of the Wiener filter-two a posteriori filters and two recursive filters. The effectiveness of the filters in separating signal from noise was tested in two simulations with known signal, and both simulated noise and real spontaneous brain wave activity. Correlation coefficients between the known test signals and filtered and unfiltered averages of test signal plus noise showed no significant difference between filtered and unfiltered averages.