Intractable complex partial and diencephalic seizures in 1 patient are being treated effectively by intermittent daily electrical stimulation in the right thalamus in conjunction with phenytoin, 200 mg/day, Electrical stimulation in the right thalamus was found to suppress spike and sharp wave discharge activity temporarily in the right thalamus and in the left parietal and right scalp leads. It was postulated that beneficial effects from electrical stimulation were due to electrically ‘jamming a low-threshold discharge system’.