Significance of focal and lateralized beta activity in the EEG.

In a group of 16,432 EEGs studied in a five year period, a total of 43 with focal, lateralized or paroxysmal beta activity were noted. The focal beta activity was mainly seen in children suffering from intractable seizures secondary to A-V malformation, porencephalic cysts or tumors. This was practically an epileptiform discharge with a high clinical pathologic correlation.