Alpha rhythm onset detector based on localized EEG sensor

The goal of this study is to detect the onset of alpha rhythm in the electroencephalography (EEG) signal after eye closure. We developed an algorithm that detects the alpha rhythm onset by analyzing the FFT of an EEG signal, obtained by means of a localized sensor in the occipital zone, developed with specific characteristics for alpha rhythm acquisition. The EEG signal of eight subjects was recorded while they were performed a simple task of opening and closing the eyes and annotated the eye closure event with a manual triggering switch. The results show that, in average, the latency of the alpha rhythm onset in this group of subjects is 1.01 s, with a standard deviation of 0.49 s. Keywords— Electroencephalography (EEG), eye closure, alpha rhythm, Fast Fourier Transform (FFT), signal processing.