Banned episodes of Pokémon

The Pokémon anime debuted in Japan on April 1, 1997, with a total of 953 episodes as of January 19, 2017. However, for various reasons, some have been taken out of rotation of reruns in certain countries, while others were altered or completely banned.

"Dennō Senshi Porygon" (でんのうせんしポリゴン^?, Dennō Senshi Porigon, translated as "Cyber Soldier Porygon", though more commonly referred to as "Electric Soldier Porygon") aired on TV Tokyo in Japan on December 16, 1997 at 6:30 PM Japan Standard Time. This episode was claimed to be dangerous for health. 20 minutes into the episode, there is a scene in which Pikachu stops some vaccine missiles with its Thunderbolt attack, resulting in a huge explosion that rapidly flashes red and blue lights. Although there were similar parts in the episode with red and blue flashes, an anime technique called "paka paka" made this scene extremely intense, for these flashes were extremely bright strobe lights, with blinks at a rate of about 12 Hz for about 5 seconds in almost fullscreen, and then for 2 seconds outright fullscreen.

At this point, viewers started to complain of blurred vision, headaches, dizziness and nausea. A few people even had seizures, blindness, convulsions, and lost consciousness. Japan's Fire Defense Agency reported a total of 685 viewers, 310 boys and 375 girls, were taken to hospitals by ambulances. Although many victims recovered during the ambulance trip, more than 150 of them were admitted to hospitals. Two people remained hospitalized for over 2 weeks. Some other people had seizures when parts of the scene were rebroadcast during news reports on the seizures. Only a small fraction of the 685 children treated were diagnosed with photosensitive epilepsy.

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Wikipedia