Here we go, I thought, another video game story - but no, it's the proper board version of Mahjong that has apparently been linked to epilepsy in the media this time.
The Hong Kong Medical Journal has a paper detailing 23 cases of people who had "suffered mahjong-induced seizures"
The way real mahjong is played is a fast-moving social game with four people, often involving gambling, and can go on for some time. The suggestion appears to be that concentrating intently on rapidly moving objects for a great length of time (after one to 11 hours of playing, according to the report) in an intense environment can bring on seizures.
I doubt this will lead to an uproar with people insisting that their grandparents be protected from these dangerous games, though...