The photoparoxysmal response: the probable cause of attacks during video games

Photic stimulation is part of a typical EEG in most countries, especially to check on the photoparoxysmal response (PPR). Interest in this response was enhanced in 1997 when hundreds of Japanese children had attacks while viewing a TV cartoon called "Pokemon." The overall prevalence of the PPR among patients requiring an EEG is approximately 0.8%, but 1.7% in children and 8.87% in patients with epilepsy, more often in Caucasians and females. Autosomal dominant inheritance is indicated, and this response is seen especially at the wavelength of 700 nm or at the flicker frequency of 15-18 Hz. The PPR extending beyond the stimulus carries no increased risk of seizures. Prognosis is generally good, especially after 20 years of age. Attention to PPR has been increased with the advent of video games, and the evoked seizures from these games are likely a manifestation of photosensitive epilepsy. Drug therapy has emphasized valproic acid, but Levetiracetam has also been successful in eliminating the PPR.