The electroencephalographic findings in 80 children with convulsive disorders occurring during the first year of life were analysed in order to investigate the qualitative and quantitative aspects of paroxistic patterns. The following resuts were obtained: 1) the focal discharges were most commonly found over temporooccipital leads; 2) multiple focal discharges were more frequent recorded during sleep tracings; 3) there was no positive correlation between the site of the focus in EEG and concomitant clinical signs; 4) there was no positive correlation between bilateral or focal paroxystic activity and the types of seizures; 5) the initially focal course of a generalized seizure can be recorded on EEG, but the foci are inconstants and transients; 6) the inconstancy of focal discharges, the absence of bilateral paroxysmal pattern and the variability of convulsive phenomenon are related to the cerebral imaturity.