Dennō Senshi Porygon (でんのうせんしポリゴンDennō Senshi Porigon literally "Computer Soldier Porygon", although most commonly translated as "Electric Soldier Porygon",Google Translated as "Polygon's Den Usenshi" ), is an episode from the popular children's anime Pokemon, which was infamous for using visual effects that caused seizures in a substantial number of Japanese viewers, an incident referred to as the "Pokémon Shock" (ポケモンショック Pokémon Shokku?) by the Japanese press. Six hundred and eighty-five viewers were taken to hospitals, but only two people remained hospitalized for more than two weeks. Due to this, the episode has been banned worldwide. After the shock, the Pokémon anime went into a four month hiatus, and it returned on TV Tokyo in April 1998. Since then, the episode has been parodied and referenced in cultural media, including episodes of The Simpsons and South Park.


"Dennō Senshi Porygon" aired in Japan on December 16, 1997 at 6:30 PM Japan Standard Time. The episode, which was broadcast over thirty-seven TV stations that Tuesday night, held the highest ratings for its time slot, being watched by approximately 4.6 million households. {C 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 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 approximately 4 seconds in almost fullscreen, and then for 2 seconds outright fullscreen. {C 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 that 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. Later studies showed that 5-10% of the viewers had mild symptoms that did not need hospital treatment. 12,000 children who did not get sent to hospital by ambulance reported mild symptoms of illness, however their symptoms more closely resembled mass hysteria than a grand mal seizure. A study following 103 patients over three years after the event found that most of them had no further seizures. Scientists believe that the flashing lights triggered photosensitive seizures in which visual stimuli such as flashing lights can cause altered consciousness. Although approximately 1 in 4,000 people are susceptible to these types of seizures, the number of people affected by this Pokémon episode was unprecedented.

An article attacking the entire Japanese animation industry soon appeared in USA Today. Written by Jefferson Graham and Tim Friend, it confidently contended that "American children aren't likely to suffer seizures provoked by TV cartoons", mainly because U.S. networks do not air the "graphic Japanese cartoons known as anime". Ron Morris at stated, however, that "there was nothing graphic about the scene or the show – the effect was caused by an unlucky combination of factors".The incident, which was referred to as the "Pokémon Shock" (ポケモンショック Pokemon Shokku?) by the Japanese press, was included in the 2004 edition and the 2008 Gamers Edition of the Guinness World Records book, with the dubious honour of holding the record for "Most Photosensitive Epileptic Seizures Caused by a Television Show".


The news of the incident spread quickly through Japan. The following day the television station that had aired the episode, TV Tokyo, issued an apology to the Japanese people, suspended the program, and said it would investigate the cause of the seizures. Officers from Atago Police Station, acting on orders from the National Police Agency, questioned the program's producers about the cartoon's contents and production process. The Ministry of Health, Labour and Welfare held an emergency meeting, discussing the case with experts and gathering information from hospitals. Video retailers across the country pulled the series from their rental shelves.

Reaction was swift on the Tokyo Stock Exchange, and the Nintendo shares went down 400 yen (almost 5%) the following morning to 12,200 yen as news of the incident spread. Nintendo produces the game upon which the Pokémon cartoon series is based. Then-president of Nintendo, Hiroshi Yamauchi, said at a press conference the day after the episode had aired that the video game company was not responsible since the original Pokémon game for its Game Boy product was presented in black and white.

After the airing of "Dennō Senshi Porygon", the Pokémon anime went into a four month hiatus until it returned in April 1998. After the hiatus, the time slot changed from Tuesday to Thursday. The opening theme was also redone, and black screens showing various Pokémon in spotlights were broken up into four images per screen. Before the seizure incident, the opening was originally one Pokémon image per screen. Before the beginning of the reairing, "Anime: Pocket Monster Problem Inspection Report" (アニメ ポケットモンスター問題検証報告 Anime Poketto Monsutā Mondai Kenshō Hōkoku?) was shown. Broadcast in Japan on April 16, 1998, a woman named Miyuki Yadama went over the circumstances of the program format and the on-screen advisories at the beginning of animated programs. Many Japanese television broadcasters and medical officials got together to find ways to make sure this never, ever happened again. They established a series of guidelines for future animated programs, including:

  • Flashing images, especially those with red, should not flicker faster than three times per second. If the image does not have red, it still should not flicker faster than five times per second.
  • Flashing images should not be displayed for a total duration of more than two seconds.
  • Stripes, whirls and concentric circles should not take up a large part of the television screen.

The episode itself has never been broadcast again in any country. The episode was dubbed and altered in the United States by 4Kids Entertainment to slow down the flashing lights, but was never broadcast. In an effort to put the event out of the public's minds and prevent trauma, the anime has not featured Porygon in any subsequent episodes. Its second-generation evolution, Porygon2, is the only second-generation Pokémon to never make an appearance in the anime. Its fourth-generation evolution, Porygon-Z, has not appeared in the anime either.

Cultural referencesEdit

The "Pokémon Shock" incident has been referenced many times in popular culture, including an episode of The Simpsons entitled "Thirty Minutes over Tokyo". In the episode, the Simpson family travels to Japan. When they arrive in Japan, Bart is seen watching a cartoon featuring robots with flashing eye lasers, and asks: "Isn't this that cartoon that causes seizures?", and the on-screen character's flashing eyes proceed to give him a seizure. Soon everyone in the room is having a seizure (though initially Homer spasms on the floor willingly because everyone else was doing it). The name of the cartoon is revealed to be Battling Seizure Robots. The end credits sequence of the episode consist entirely of the usual credits superimposed over a fullscreen image of the robot's eyes flashing. {C An episode of South Park that first aired in November 1999, called "Chinpokomon" (a portmanteau of "Chinpo" (Japanese for Penis) and "Pokomon", revolves around a Pokémon-like phenomenon, called Chinpokomon, which the children of South Park become obsessed with. Chinpokomon toys and video games are sold to American children in South Park by a Japanese company. The company's president, Mr. Hirohito, uses the toys to brainwash the American children, making them into his own army to topple the "evil" American empire. These toys included a video game in which the player attempts to bomb Pearl Harbor. While playing this game, Kenny has an epileptic seizure and later dies, in reference to the Pokémon seizure incident. {C In the pilot episode of Drawn Together, Ling-Ling, who is a parody of the Pokémon character Pikachu, states that his goal in the Drawn Together house is to "destroy all, and give children seizures". There follows a scene with flashing lights, a direct reference to this episode. In So Yesterday, a novel by Scott Westerfeld, this episode is mentioned and shown to three of the characters, one of which ends up having a seizure as a result. The flashing red light that caused the seizure is also used in the story telling elements.