Fluctuations in Human Electroencephalogram

The human electroencephalogram (EEG) that records the brain electrical activities shows a high degree of fluctuations both spatially on the scalp and temporally over various time scales. Since the human brain dynamics is that of a highly nonlinear system, we shall examine the nature of the fluctuations in the EEG time series in the framework of nonlinear analysis. By using detrended fluctuation analysis we find scaling behaviors that provide very useful and hitherto unrealized information about the characteristics of the brain function.