Minimal repetition evoked potentials by modified adaptive line enhancement.

A new method called modified adaptive line enhancement (MALE) to obtain 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 brain-stem auditory evoked potential. The signal distortion are 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 potential can be obtained with less than 40 repetitions using MALE method compared to 2000 required if conventional ensemble averaging method is used.