Most people are familiar with photosensitive epilepsy where certain patters or light or moving images can cause a seizure. Still images with certain patterns can also cause seizures. Researchers from University Medical Center (UMC) Utrecht in the Netherlands believe they know why.
As researchers sifted through years of old scientific literature, they discovered associations between images that induced a seizure and gamma oscillations in the brain. Gamma oscillations are a brain wave pattern characterized by neurons that fire rhythmically at approximately 50 times per second. These brain wave’s are “strongly driven by certain kinds of visual patterns” and are measured using an EEG. If their rhythmic firing pattern in the visual cortex is disrupted from viewing an image, a seizure is more likely. For example, images that caused the neurons to fire in unison were less likely to induce a seizure than those that caused them to fire out of unison.
Researchers found that black and white bar patterns were used and more issues occurred with vertical bars versus horizontal bars. Some researchers and physicians emphasize that while only black and white bar patterns were used, other patterns and/or colors could cause issues as well.
Researchers caution that their hypothesis is drawn from historical literature only. However, they are planning on testing these findings using random patient population.
****The original article below contains a link at the bottom to view the “potentially seizure-inducing pattern.” Please use caution, especially if you have photosensitive epilepsy.****