“Gangnam Style” is dangerously flashyPosted: 10/12/2012
Another flashy music video on YouTube, and this one’s been viewed hundreds of millions of times since its July launch. The viral phenomenon “Gangnam Style” by Korean pop star PSY has lots of flash, but surprisingly, only one instance of exceeding seizure safety guidelines.
In the problem sequence, images of PSY rapidly alternate with images of another Korean performer, Kim Hyun-a. Alternating between the bright, contrasting images at a rate of 3 times per second or more creates a flash effect capable of inducing a seizure.
The wildly popular“Gangnam Style” video was followed several weeks later by the release of a female version,“Oppa Is Just My Style,” that includes more sequences with Ms. Hyun-a. The second video has considerably more flashing sequences that could easily trigger seizures in individuals with photosensitive epilepsy.
In the upper left of the screen grab at left (click on it to enlarge) you can see a dance sequence that is being analyzed for seizure safety. The accompanying graph indicates levels of flash (luminance) that fail to meet photosensitive epilepsy safety guidelines. Visible at the bottom of the screen are the individual frames that make up the moving sequence. The flashing effect is created by the alternating frames of bright and dark images.
How come you haven’t heard about seizures from the #1 YouTube video?
- Viewers may not maximize the video to fill the computer screen. Therefore the image is too small to affect enough neurons to cause seizures.
- Viewers are not staring continually at the screen—maybe they’re laughing, doing the horse dance, or straining to figure out the lyrics
- The seizures are happening but without many outward signs, so they are not recognized as seizures.