Veronica With Four Eyes

How To Check Videos For Flashing Lights

Before I watch videos, I have to check with someone to see if the video contains any flashing or strobe lights. This can seem like a question that is nearly impossible to answer, since flashing and strobe lights seem to be everywhere- the lights on a school bus, the fire alarm, and even camera flashes can be disorienting to someone who is photosensitive. Luckily, I have had many awesome friends and teachers who check videos for me ahead of time to ensure that I don’t get any migraines from whatever we are watching. Today, I will be sharing how to check videos for flashing lights to see if they could trigger an adverse medical reaction such as a seizure, migraine, or vertigo.


I have a brain condition called Chiari Malformation that causes me to have many neurological symptoms, with one of them being photosensitivity and chronic migraines triggered by flashing lights. I have dealt with this issue since ninth grade and at one point I was so sensitive that even small amounts of flashing lights could be a problem. My condition has changed over time though, and so have my triggers. I now find that I am especially sensitive to white, red, and blue lights that flash or strobe quickly. Migraines aren’t the only condition that can be triggered by strobe lights though. Some people with epilepsy, PTSD, ADHD, autism, and other photosensitive conditions may experience adverse health effects due to flashing lights.

I am not advocating for the removal of flashing and strobe lights from existence, I am sharing how I personally avoid a known medical trigger for me and how I ask people close to me to help me in doing so.

Related links

Potential triggers

Outside of obvious triggers like full screen strobe lights and rave scenes, here are some less obvious sources of flashing lights in video content that can trigger an adverse reaction.

Older videos

Many black-and-white videos contain floaters and changing lighting conditions that resemble flickers of light, especially in historical videos like those found in archives. As recording and audiovisual technology has improved over time, so has the clarity of videos, which dramatically reduces the potential issues mentioned above. While this trigger may only be relevant for people with severe sensitivities to flashing lights, it’s still important to note and can be remedied by showing the highest resolution video available.


I was watching a video in one of my classes that my teacher said they had checked beforehand. Unfortunately, they didn’t realize that flashes of lightning are the equivalent of nature’s strobe lights. I ended up in the nurse’s office not too long after a lightning storm came up. After that, I started asking specifically if there was lightning in any of the videos we would be watching. I also would ask about fireworks, though those are less common.

Flashing backgrounds

Many movies that feature scenes with police cars in the background, nightclubs, or concerts have blue, white, and red flashing lights going off in the background. These may be very obvious or hidden in the background, but making a note of flashing background scenes is an easy way to ensure that every scene is accounted for.

Anything that explodes

When I was in seventh grade, my class watched a movie that featured several gunshots, bombs, and similar weapons being discharged rapidly. This created a large amount of flashing lights. While I didn’t realize it at the time, I ended up feeling very disoriented and felt sick. At the time I thought it was just because of the blood in the movie. Guns, explosions, cannons, and other weapons flash when used, so make sure to check for scenes like this in videos.

Camera flashes

Rooms filled with journalists and paparazzi often contain several camera flashes going off in short intervals which simulates strobing lights. While one camera flash may not trigger a reaction, it’s still important to note camera flashes due to the white lights.

Related links

How to warn people about flashing lights in videos

Provide as much information about the types of lights as you can

Before sending me a video, my friend sent me a message telling me about the video. There was a scene with slow blinking yellow lights that took up half the screen. Since slow flashing lights don’t trigger a reaction for me, I thanked them for the warning and watched the video. In a different situation, I was told there was a scene in a video with fast flashing red and blue lights, which are more likely to trigger migraines. I declined to watch that video since it was more likely to trigger a reaction.

Write down when the scenes begin and their length

For a video in one of my assistive technology classes, the professor told us there were two scenes that contained flashing lights. The teacher provided timings (such as 1:47 into the movie) as well as information about the scene that came up right before the lights so students could close their eyes if needed. They also told us the line of dialogue that followed the scene so we would know when it was safe to look up. I had warned the professor about my medical condition ahead of time and they were happy to accommodate.

Have an audio signal to warn about lights

One of my friends who is sensitive to flashing lights due to a brain tumor asked their teacher to give an audio signal such as a beep before there are scenes with flashing lights or rapidly moving images, and then another beep after the scene ends. They liked this method because it was discreet and the teacher didn’t mind doing it. In a similar example, my college basketball game has flashing lights before the game and the announcer yells “lights out” about five seconds before they begin so that people can close their eyes if they want to, and then my friend signals me when the lights end by tapping my shoulder.

How many lights are too many?

Some movies have several scenes with flashing lights that are either very long or integral to the plot or understanding of the video. In times like these, my teachers would give me the option to skip the video and complete an alternative assignment instead. Another option is to have the student close their eyes and listen to audio description.

Related links

More tips for checking videos for flashing lights

  • Individual triggers may vary- talk to the person who experiences sensitivity to strobe or flashing lights about what types of lights can be a trigger, or if certain colors need to be avoided
  • Avoid tagging videos with flashing lights as epilepsy or seizure, as these are often educational tags used for people living with these conditions. Instead, use tags like “tw epilepsy” for trigger warnings
  • For some people living with photosensitivity, watching videos in a well lit room can help to reduce the negative effects of flashing lights
  • Another option for listening to videos with flashing lights is to enable a screen curtain on the device or cover the screen so that light does not leak through
  • Some streaming services have started adding tags to videos that contain a significant a significant amount of strobe or flashing lights, and the website Does The Dog Die has information on strobe light triggers as well for popular movies.

How to check videos for flashing lights. Tips for checking videos for flashing lights and strobe lights for viewers with migraines, seizures, or vertigo