1. Of over 500 patients who received electric convulsive therapy, 2 exhibited spontaneous generalized convulsions 6½ to 8 weeks after termination of treatment. These 2 patients had never had seizures prior to treatment, nor were there any epileptic manifestations in any of the family members.2. Pre-treatment EEGs are reported for the first time in patients exhibiting spontaneous convulsions subsequent to therapy. In both instances, the brain-wave tracings were abnormal prior to shock.3. It is concluded that spontaneous convulsions following convulsive therapy are prone to occur only in those patients who have latent convulsive tendencies as revealed by the EEG.4. The suggestion is made that pre-shock EEGs are particularly indicated in patients who give histories of previous convulsions in childhood or later life, or who have family members exhibiting epileptic manifestations.Abstract Teaser