Minimal repetition evoked potentials by modified adaptive line enhancement

A method called modified adaptive line enhancement (MALE) for obtaining evoked potentials with minimum stimulus repetitions is described. The theory of MALE is developed and the assumptions made are tested and shown to be adequate in the case of brainstem auditory evoked potential. The signal distortion is characterized, and methods to alleviate the problem are developed. Using the weighted exact least squares lattice algorithm, the MALE method is implemented and applied to real data. It is shown that brainstem auditory evoked potentials can be obtained with less than 40 repetitions using the MALE method, compared to the 2000 required if the conventional ensemble averaging method is used.