Developmental studies on EEG spectral analysis in mentally retarded children.

The EEG developmental characteristics of 36 mentally retarded infants were investigated by auto-power spectrum analysis. A significant positive correlation with age was found in the dominant frequency in all of the three regions, occipital, central, and frontal. A tendency for the generalized component to increase was found in 3- to 5-year-old subjects as compared with those aged 6 months to 1 year and 7 months. Developmental coherence characteristics could not be found. The peak components tended to show higher coherence values in the frontal-central relation than in the central-occipital and occipital-frontal ones.