Dennō Senshi Porygon

During its sole broadcast in Japan on December 16, 1997, a scene with flashing lights induced photosensitive epileptic seizures in children across the country.

[citation needed] In the episode, Ash and his friends find that there is something wrong with the Poké Ball transmitting device at the local Pokémon Center.

Towards the end of the episode, Pikachu stops a wave of missiles with an attack, resulting in an explosion that is depicted by rapid flashing lights that fill the screen.

Ash, Misty, Brock make their way to the nearest Pokémon Center to heal Pikachu's exhaustion, where they discover that the Poké Ball transmitting device is malfunctioning.

[3][4] Twenty minutes into the episode, Pikachu stops missiles with his Thunderbolt attack, resulting in an explosion that rapidly flashes red and blue lights.

[3] There was a higher incidence in the 11 to 15-year old demographic, with over 90% of the affected being from middle and high school age ranges; the oldest victim was a 58-year old from Kanagawa Prefecture.

[1] The following day, the television station that had originated the lone broadcast of that episode, TV Tokyo, issued an apology to the Japanese public, suspended the program, and said it would investigate the cause of the seizures.

All 37 episodes of Pokémon: Indigo League were rerun on Kids Station in Tokyo leading up to the show's return on April 16, 1998, with airing of "Pikachu's Goodbye" and "The Battling Eevee Brothers".

[1] The Pokémon anime has not featured Porygon or its evolutions, Porygon2 and Porygon-Z, in any subsequent episodes outside of brief cameos, despite Pikachu being the one to cause the seizure-inducing strobe effect.

The following table lists the final episode of the Pokémon anime that aired on the station before the hiatus and the title of the program that initially replaced its timeslot.

[21] According to then-president of Nintendo of America, Minoru Arakawa, he had first raised the possibility of bringing Pokémon to the US market three weeks before this episode aired.

However, Arakawa believed that the coverage of the incident in the US was fairly calm compared to Japan, as the US had previously reported on cases of epilepsy being induced by video games so the concept was already well-known—instead, he argued that it only increased the series' name recognition.

[22] In his book Pokémon Story, Masakazu Kubo of ShoPro notes that initially the incident increased the reluctance to bring the series to the US market, but due to concerns that the entire Pokémon TV show could end up being banned from Japanese TV, instead it was decided that pursuing an American release was essential to repairing the series' reputation in Japan.

[22] Starting on January 4, 1998, ShoPro conducted in-person negotiations with Nintendo of America for licensing the Pokémon anime for the US market.

Footage may either clear or fail checks, or "pass with a warning" in which case the video's luminance is automatically adjusted to mitigate potential effects.

[citation needed] After the incident, TV broadcasters voluntarily added on-screen warnings to shows targeted at young children encouraging viewers to watch anime in a well-lit room and to sit far away from the television set.

[27] The "Pokémon Shock" incident has been parodied many times in popular culture, including a 1999 episode of The Simpsons, "Thirty Minutes over Tokyo".

Porygon remains obtainable in the video game series, is featured in manga adaptations, included in merchandising, and referenced in advertising thereof.