The research on the human brain, which is one of the most complex nonlinear dynamics systems, has become one of the hottest areas and will be full developed in the 21st century. After the discovery of electroencephalogram (EEG) in 1929 by Hans Berger, EEG has been utilized as a non-invasive method to study the brain and plays an important role in many areas. In biomedicine, EEG is an efficient tool to diagnose and treat some brain disorders, and in cognitive science, EEG is a key to open the do...