Improved estimation of EEG evoked potentials by jitter compensation and enhancing spatial filters

We propose in this paper a new technique to investigate the Event-Related Potentials, or Evoked-Response Potentials, in the electroencephalographic signal. The multidimensional electroencephalographic signal is first spatially filtered to enhance the Evoked-Response Potentials using the xDAWN algorithm and, second, the single trial latencies (whatever their origins: physiological or electronical) are estimated by maximizing a cross correlation without any a priori model. The performance of this approach is illustrated on two classical P300-Speller electroencephalographic databases (BCI Competition II and III). The single-trial distribution of P300 Evoked-Response Potential is deblurred using the proposed resynchronization algorithm for applications in particular to Brain Computer Interfaces.