Optimal alignment of BAEPs by modelling their non stationarities

In this paper, we are interested in extracting Brainstem Auditory Evoked Potentials (BAEPs) from the electroencephalogram (EEG). We focus on the problem of BAEP non-stationarities, in particular those observed in some endocochlear pathologies assuming random BAEP delays due to an abnormal behaviour of the cochlea. The technique developed in this paper, called the Time Delay Correction (TDC) method, is based on modelling BAEP non stationarities by considering each BAEP, delayed according to a specific model. The suggested mathematical model is considered to be a sum of sinusoids. We show that the optimal solution allows the estimation of cochlea dynamics allowing the alignment of all the recorded BAEPs. A better measurement of latencies as well as conductions time are then obtained. Simulation results seem to be very interesting.