A case of a girl (10 years old) with a psycho-organic syndrome plus headache without signs of clear intracranial hypertension is related. The diagnosis of neurocysticercosis was made by CSF abnormalities. PLEDs over the left cerebral hemisphere were recorded at the first day after treatment with praziquantel (50mg/kg/day during 21 days). The first CT scan was normal and just after the treatment showed a prominent left cerebral hemisphere involvement, despite parenchymatous dissemination of cysticerci was bilateral. The treatment was successful and the patient became asymptomatic in the two years follow-up. The neurophysiologic aspects of this EEG abnormality is also discussed.