“…It is required to take into account the time variation of the relevant frequency components (Liu et al, 2005;Herman et al, 2008;Al-Ani and Trad, 2010;Hema et al, 2010). Another part of the success of a BMI is dependent on subject's training and motivation, making them able to learn to control the intensities of specific frequency bands, which can be used for the communication feature (Herman et al, 2008;Al-Ani and Trad, 2010;Hema et al, 2010). Herman et al (2008) presented an extensive comparative study involving different approaches to spectral signal representation such as power spectral density techniques, atomic decompositions, timefrequency energy distributions, continuous and discrete wavelet approaches, and also various classifiers aiming at distinguishing between right and left hand motor imageries.…”