[Rhythmic alpha activity in the EEG of premature and newborn infants]

The EEG of the newborn consists of a mixed activity which varies from 1 to 22/s. Waves in the alpha band may occur, but they indicate cerebral dysfunction if they are seen in a rhythmic uninterrupted sequence. Eight newborns who showed rhythmic alpha activity in their EEG are included in our study. This activity occurred together with rhythmic theta waves or was followed by them as part of ongoing electrographic seizure activity. All newborns studied were very sick. Three suffered from severe perinatal asphyxia with persistent fetal circulation; in addition one of them had bacterial meningitis. Two infants suffered from herpes encephalitis. In those cases the rhythmic alpha activity temporarily showed a certain periodicity. This EEG pattern was also seen in a small for gestational age premature infant who had septicemia and subarachnoid hemorrhage and in two extremely premature babies with intraventricular hemorrhage. Four infants were curarized. All of the others also had clinically observed seizures. Rhythmic alpha-activity in the neonatal EEG represents an electrical seizure discharge. It may also occur in premature infants who suffer from intraventricular hemorrhage. Obviously it does not have a diagnostic value. The prognostic value depends upon the underlying disease and the grade of background suppression in the EEG. Anticonvulsant therapy should be administered early using a sufficient dosage.