If you go to see Incredibles 2, which just had the most successful opening at the box office ever for an animated movie, don't be surprised if you notice signage in your local theater that includes a special warning about the film. After moviegoers pointed out on social media that some scenes contain lots of flashing lights, theaters are alerting people that the movie could impact people with certain health conditions, like epilepsy.
The warnings are the result of an online campaign by Veronica Lewis, who raised the issue on Twitter that the movie could be a potential trigger for things like seizures or migraines, specifically due to the villain Screenslaver, who uses bright, flashing lights as a weapon. Several others on Twitter also echoed her concerns.
“These scenes are also spread out across the movie and often come without warning,” Lewis, who has a visual impairment, tweeted. “My descriptive audio device warned me about the larger scenes, but other times it was light strobe lights came out of nowhere for no reason.” Lewis made it clear that she’s not calling for a boycott of the movie, but she wished there had been a warning about the strobe lights in advance.
Lewis tells SELF that she wanted to tweet about this to educate people about the fact that special effects like this can be a health hazard for people with certain conditions.
“I figured if I can even help one person avoid an adverse health effect from strobe lights, then I would be thrilled,” she says.
Lewis, who suffers from photosensitive migraines that can be triggered by these kinds of lights, says she’s been “blown away” by the amount of people who have thanked her for writing her Twitter thread. Disney has also since issued a warning and instructed theaters to post their own warnings for viewers about the flashing lights before they see the movie, Variety reported. Many theaters have posted signs at the ticket counter.
SELF has reached out to the Walt Disney Company for comment and will update this post when they respond.
Flashing lights like this can be potentially dangerous to people with health conditions that are associated with photosensitivity, meaning they can be triggered by visual patterns.
Photosensitivity is a general term that's typically used to describe an abnormal light sensitivity. For some people, migraines can be triggered by light and visual patterns.
But many movie theaters that are warning people about the strobe lights in Incredibles 2 are specifically directing the warnings at people with photosensitive epilepsy, which is a type of epilepsy characterized by seizures that are trigged by visual stimuli, like strobe lights.
Epilepsy is a central nervous system condition characterized by recurrent seizures.
There are several types of epilepsy, and they differ based on the type and pattern of seizures patients experience as well as their age and where in the brain their symptoms originate. Only about 3 percent of people with the condition can have seizures after being exposed to flashing lights at certain intensities or with certain visual patterns, according to the Epilepsy Foundation. More common triggers of seizures in someone with epilepsy include lack of sleep, alcohol, and stress, Jessica W. Templer, M.D., a neurologist and epilepsy expert at Northwestern Memorial Hospital, tells SELF.
Photosensitive epilepsy is more common in children and adolescents, according to the Epilepsy Foundation. One of the more common types of epilepsy that is photosensitive is a subtype of juvenile myoclonic epilepsy (a form of epilepsy with seizures that start anywhere between 5 and 16 years of age), Dr. Templer says.
Interestingly, strobe lights are not the only thing that can trigger photosensitivity for people with epilepsy. Some people also find their seizures are triggered by patterns of light caused by things like the flashing lights on emergency vehicles, sunlight reflecting on water, or stripes of contrasting colors. Doctors can see abnormalities in brain activity during an electroencephalogram (EEG), which can also be used to test for photosensitivity, David Ficker, M.D., a professor of neurology at the University of Cincinnati Epilepsy Center and chair elect of the Epilepsy Foundation Professional Advisory Board, tells SELF.
Treatment for epilepsy is usually tailored to each individual patient and may include medication, surgery, stimulation of the vagus nerve, and changes in nutrition. But in some people with epilepsy who are light sensitive, strobe lights can trigger a seizure even if they’re on medication and their epilepsy is well controlled, Dr. Ficker says.
Unfortunately, there isn't one handy resource that you can refer to in order to see if a movie you're interested in could increase the risk of an epileptic seizure, Dr. Templer says, so you often have to try to do your homework in advance. (The Epilepsy Foundation is a good place to start.) But if you do happen to stumble across a scene where there are flashing lights, you can reduce your risk of having a seizure by looking away and closing your eyes, Dr. Ficker says. Still, it's always better to know ahead of time.