Electroencephalographic abnormalities in borderline personality disorder.

Epilepsy and non-localized brain dysfunction have been invoked, among others, as underlying factors in borderline personality disorder. We have recorded 58 electroencephalograms in 20 borderline patients, first after complete drug washout and then under carbamazepine or placebo double-blind treatment. Taking into account only definite abnormal tracings, we found a 40% incidence of abnormal diffuse slow activity. No patient disclosed focal or epileptiform EEG features. Carbamazepine did not appear to modify the electroencephalogram.