Effects of clonazepam on self-induced photoparoxysmal responses.

A 5-year-old girl exhibited daily episodes of repetitive blinking lasting 5-10 s. Electroencephalography (EEG) revealed marked photoparoxysmal responses (PPR) at 3-20 Hz of photic stimulation and diffuse spike-wave bursts during sleep. A 24-h video EEG identified 11 episodes of repetitive blinking, 3 of which resulted in widespread spike-wave discharges. These suggested that the behavior of the patient represented self-induction of PPR. Valproate sodium was ineffective in decreasing PPR, as revealed by EEG, and the frequency of blinking episodes, but clonazepam attenuated PPR and significantly decreased the blinking behavior.