EEG developmental stages.

Data in the literature show that in humans the fraction of the total electroencephalographic (EEG) energy that appears in the alpha frequencies rises from about zero at birth to about 70% in adults. This rise is shown to occur mainly in 5 stages, the ages of which correlate with those of stages of increase in brain weight. Supporting the correlation are data on gender dimorphism in humans in both brain weight and EEG development, as well as limited data on development in kittens, rats, mice, and guinea pigs.