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Introduction: Visually evoked seizures have been reported for almost 2,000 years. This source of seizure activity, however, seems to have increased recently with the advent of new technologies used for television and computer games., Methods: The present paper reviews the literature regarding this interesting phenomenon., Results: After our review, it does appear that visually evoked seizures have increased in frequency during the twentieth century., Conclusions: We believe that knowledge of visually evoked seizures may aid neuroscientists in further exploration of the pathophysiology of seizure activity and its related preventive measures. Further studies are necessary to prove the etiology of such seizure activity.

Purpose: This report summarizes background material presented to a consensus conference on visually provoked seizures, convened by the Epilepsy Foundation of America., Methods: A comprehensive review of literature was performed., Results: Photosensitivity, an abnormal EEG response to light or pattern stimulation, occurs in approximately 0.3-3% of the population. The estimated prevalence of seizures from light stimuli is approximately 1 per 10,000, or 1 per 4,000 individuals age 5-24 years. People with epilepsy have a 2-14% chance of having seizures precipitated by light or pattern. In the Pokemon cartoon incident in Japan, 685 children visited a hospital in reaction to red-blue flashes on broadcast television (TV). Only 24% who had a seizure during the cartoon had previously experienced a seizure. Photic or pattern stimulation can provoke seizures in predisposed individuals, but such stimulation is not known to increase the chance of subsequent epilepsy. Intensities of 0.2-1.5 million candlepower are in the range to trigger seizures. Frequencies of 15-25 Hz are most provocative, but the range is 1-65 Hz. Light-dark borders can induce pattern-sensitive seizures, and red color also is a factor. Seizures can be provoked by certain TV shows, movie screen images, video games, natural stimuli (e.g, sun on water), public displays, and many other sources., Conclusions: Recommendations on reducing risk of seizures have been developed by agencies in the United Kingdom, Japan, and the International Telecommunications Union, affiliated with the United Nations. The Epilepsy Foundation of America has developed a consensus of medical experts and scientists on this subject, reported in an accompanying work.