Electroencephalographic quantification by time domain analysis in normal 7--15-year-old children.

Automatic EEG analysis was performed on 239 apparently healthy school age children. The children were classed in 3 age groups: (1) average age of 7; (2) average age of 11; (3) average age of 15. A time analysis method, comparable to classical visual analysis, permitted quantification of the records. The mean amplitude, frequency and percentage time for alpha and theta rhythms were determined for each subject for fronto-central and centro-occipital derivations bilaterally. Records were performed during periods of rest with eyes open and eyes closed. During hyperventilation, records were taken with eyes closed. The normal ranges of parameters were determined by calculating their means and standard deviations, for each age group under each recording condition. Delta and beta rhythm values were not calculated, because of their rarity in this apparently normal sample. The precision obtained by automatic analysis could not have been obtained by means of classical visual analysis. The present findings suggest that the statistical analysis of well-defined groups of normal and pathological children could be of significant value.