Application of adaptive filtering to steady-state evoked response

A new method to detect steady-state evoked potentials (EPs) is presented. The technique is based on a two-weight recursive least squares (RLS) adaptive filter and the T _circ ² statistic. Simulations with known sinusoids buried in Gaussian noise and in EEG noise indicate that the adaptive filter can detect signals at 3 or 4 times lower signal-to-noise ratios that the discrete Fourier transform (DFT). Qualitatively similar results were obtained with human visual evoked potential recordings.