Developmental Changes in the EEG Rhythms of Children and Young Adults

Abstract

This study analyzed the developmental trends of brain rhythms in a group of children and a group of young adults. Principal component analysis (PCA), ANOVA, as well as correlational and topographical analyses were applied to the power spectral density of spontaneous electroencephalography (EEG). Absolute and relative power data were analyzed. The PCA analysis allowed to define three sources of variability related to the classical EEG rhythms. The absolute power results showed that children have higher spectral power than young adults in all frequency bands. Relative power demonstrated that children have more spectral power in the lower frequency bands (delta and theta) while young adults have more spectral power in the higher frequency bands (alpha and beta). Scalp topography analysis showed similar distributions for the four EEG bands in both groups, although delta and theta differed slightly between age groups. Correlational and PCA analysis showed an inverse relationship between delta and alpha power during development. Posterior regions and lower frequency rhythms seem to mature earlier than other regions and frequencies.