A new EEG signal processing technique for discrimination of eyes close and eyes open

Earlier difficulties have been observed in generating control sequences for prosthesis as well as other applications when using biological signals such as EEG. This paper deals with a new methodology of using EEG and discriminating between the close/open state of the eyes. A digitized signal of duration 3 seconds is divided into 8 segments and a digital band pass (BP) filter (Butterworth) implemented to extract the noise from the alpha rhythm. The output of the band pass filter for each segment is used as a weightage factor for the same segment before filtering and the signal of each segment was processed by fast Fourier transform (FFT) and power spectra analysis. By comparing the frequency of peak power before and after processing for each segment of eyes closed and eyes opened, the results show that the two states of the eyes have been clearly discriminated.