Yes, flashing online images can set off an epileptic seizure – and Newsweek senior writer Kurt Eichenwald, a frequent critic of President-elect Donald Trump, says he’s planning legal action after just such an attack.
This isn’t the first time Eichenwald, who has epilepsy, has been hit with a griefing GIF. He reported facing a similar threat back in October when someone tagged him in a tweet showing a flashing online image of Pepe the Frog, a cartoon character that has been appropriated by extremists.
Strobe lights and rapidly flashing graphics can be epileptogenic – that is, capable of inducing seizures or other health effects for those with photosensitive epilepsy. One infamous case involved a Pokémon TV cartoon that sent hundreds of Japanese children to hospitals in 1997. (Mass hysteria may have played a role.)
In 2008, malicious Internet users posted hundreds of epileptogenic graphics to an online message board run by the Epilepsy Foundation, causing some patients to suffer headaches or seizures.
The causes of photosensitive epilepsy are poorly understood, but the phenomenon appears the primary visual cortex. In vulnerable people, the neural networks that handle rapid changes in imagery may be overly excitable, leading to sensory overload.