EEG maturation on children with different economic and psychosocial characteristics.

It has been shown that EEG maturation can be described in terms of regression equations on age of broad band EEG frequency parameters. In the present paper six groups of children with different economic and psychosocial characteristics of three countries were studied. Regression equations on age of the EEG relative power (expressed in percentages of the total EEG activity) in the delta, theta, alpha and beta bands in 8 bipolar derivations were computed in each group of children and the slopes compared with those previously published by John et al. (1980). Those children who grew up with adequate nutritional, sanitary and cultural environmental conditions showed the same slopes as U.S. and Swedish children selected with strict criteria of normality. Children nourished in poor socioeconomic and sanitary environments and who frequently had pathological personal antecedents with risk factors associated with brain damage showed either a slow maturation of the EEG characterized by smaller slopes of theta relative power or a great variance of EEG parameters and no relation of these parameters to age.