Digital signal processing of the visual evoked cortical potential-survey and future directions

The authors review the major signal processing techniques which have been developed to obtain reliable estimates of the VECP. A mathematical model for the VECP is developed. This model clearly states the general assumptions made with single VECP recordings. The major signal processing techniques used for VECP estimation are then reviewed. These techniques include Ensemble Averaging, Cross-Correlation Averaging, a posteriori `Wiener´ Filtering and Latency Corrected Averaging. Future directions are considered, including a new technique employing time-variant spectrum estimation methods