Five of New York Magazine’s top ten video games of 2016 don’t meet guidelines for reducing the risk of visually provoked seizures. Developers of these popular games could have designed the visuals in a way that lowers the seizure risk to users, but didn’t.
Guidelines for reducing the risk of seizures triggered by video images were published in 1994, when the UK required that all TV programs and advertisements meet those visual safety standards. The same guidelines for making television images safer could easily be adhered to when developing video game visuals. No regulations on seizure-inducing images in video games have ever been enacted, so game developers have no incentive to work within the guidelines.
Instead, for many years game publishers have provided a seizure warning that makes it extremely difficult for consumers to take legal action in case of a seizure. Some games may in fact conform to seizure-reduction guidelines, but because the seizure warnings appear on all games, consumers can’t know which ones are riskier. The warnings began appearing in 1991 in response to the first video-game-seizure consumer lawsuits.
What compliance with the guidelines means
Many popular games don’t meet the guidelines, as demonstrated by my testing of New York Magazine‘s favorite games. A couple of the failing games were among the top five first-person shooter games selected by Forbes.
I tested video clips from gameplay and promotional trailers for the games on the list using software that identifies video sequences that don’t comply with the guidelines. The software is designed for game developers and video producers to test their moving images for compliance.
Note that for the games that didn’t violate the guidelines, rather than list them as passing the compliance test, I’ve indicated that they did not fail the test. Although in previous posts with test results I’ve listed games that “passed” the guidelines test, I’m no longer using that terminology. That designation could too easily be misinterpreted to mean that such games will definitely not cause seizures.
Even if a game doesn’t fail the guidelines compliance test, there is still a risk of seizures, for several reasons:
- I may not have tested a portion of the game with problem image sequences
- The guidelines aren’t fool-proof. They are designed to prevent seizures in approximately 97 percent of people who have photosensitive epilepsy, the condition where visual stimuli can trigger seizures.
- Many environmental and personal health variables–such as lack of sleep or illness– can affect an individual’s vulnerability to seizures
Do you need to worry about seizures from video games?
- The vast majority (97 percent) of people diagnosed with conventional epilepsy can play video games without risking a seizure because–unless their EEGs indicate otherwise–their seizures aren’t triggered by visual effects. These people don’t want others questioning their fitness for gaming.
- People with no history of epilepsy may be most at risk. Seizures can be triggered by flash and flicker even in people with no history of seizures, which means that many don’t know they are at risk of having a visually triggered seizure until a video game brings on their first event. Of the children who had seizures during the 1997 Pokémon cartoon broadcast in Japan, only 24% had previously experienced a seizure.
- Visually triggered seizures typically begin between ages 2-18, and most commonly begin around age 12-13. Of patients age 7-19 who seek medical attention for a seizure, ten percent test positive for photosensitive epilepsy. Researchers estimate that only 25 percent of people outgrow the condition, typically in their twenties.
- It is relatively unusual but not unknown for these seizures to develop in adults. Because in many individuals a number of factors (for example, emotional state and hormone levels) affect seizure vulnerability, a seizure may not actually occur until several of these factors are present simultaneously. Even one seizure can be life-changing if it results in injury or permanently bars an individual from certain occupations.
- It is also possible to experience subtle seizures and not realize they happened. This doesn’t mean there are no seizure consequences, though. Typically after seizures one’s physical, cognitive, and emotional functioning can be impaired.
More on the guidelines and how games are tested for seizure risk
According to a Reddit post, a game that I’ve said “passed the seizure test” triggered a seizure. Recently the same game—Hearthstone—could have been implicated in a professional gamer’s seizure that happened during a live stream. What’s going on?
I write about games I’ve tested to alert readers to the games that don’t meet internationally recognized image safety guidelines. But I don’t want to create undeserved confidence that a game that passed the seizure test will be safe for anyone with photosensitive epilepsy.
Ian Hamilton, a user interface designer who specializes in and advocates for game accessibility, clarifies the role of testing this way:
“Passing the Harding test doesn’t mean that a game is safe. It means ‘reasonably safe’ because common triggers have been avoided. Something that gets a ‘pass’ can still absolutely cause seizures.”
I regularly write that your experience may differ, that I’m not trained in quality assurance, that I test excerpts of game play, and that health and lifestyle variables affect every individual’s vulnerability to seizures at any given time. Still, the meaning of my findings could be misleading without an understanding of the limitations of the seizure test itself:
- the pass/fail guidelines aren’t expected to prevent seizures in all individuals
- the test was designed for TV images, not video games
What the Pass/Fail guidelines mean
The guidelines originated in 1994, when the UK’s agency for regulating TV broadcasting (now known as Ofcom) inserted into its code of standards some technical guidelines to accommodate viewers with photosensitive epilepsy. These guidelines, based on studies of photosensitive epilepsy and consultation with Prof. Graham Harding and other photosensitive epilepsy experts, detail flash rates and spatial patterns that typically trigger seizures in people with photosensitive epilepsy. Specifications regarding saturated red images were added later, after the 1997 Pokémon incident in Japan.
Some compromises in the guidelines were made for the sake of practicality. Criteria for acceptable images (commonly referred to as the Harding test) were developed with the understanding that they would realistically protect most individuals with photosensitive epilepsy, but not all. For example, the guidelines permit images that flash at a rate of up to 3 times per second because flash at that frequency affects only 3 percent of photosensitive individuals. UK regulators decided that was “an acceptably small risk.”
The introduction to the guidelines states that their purpose is “reducing the risk of exposure to potentially harmful stimuli.” It also concedes that even when broadcasting images that comply with the guidelines,
“it is…impossible to eliminate the risk of television causing convulsions in viewers with photosensitive epilepsy.”
Applying TV guidelines to video games
There are no formal guidelines for reducing the seizure risk from video games. A 2005 consensus paper by experts on photosensitive seizures acknowledges that additional work would be required first on the existing guidelines for TV. In the meantime, it is reasonable to use the television guidelines since the impact of screen images on the visual system is the same.
The biggest challenge in applying TV specifications to video games is explained in the consensus paper:
“These principles are easier to apply in the case of fixed media (for example, a prerecorded TV show), which can be analyzed frame-by-frame. Interactive media, such as video games, may afford essentially limitless pathways through the game, depending on user actions. Therefore …in the case of video games, the consensus recommendations apply to typical pathways of play but cannot cover every eventuality of play.”**
Reducing risk going forward
In sum, a game that fails the Harding test is best avoided by those with photosensitive epilepsy. A game that passes is less likely to act as a trigger. Despite all the qualifiers, I believe there’s value in reminding people that seizures can happen to anybody, that certain video games can trigger them, and that you can lessen the risk by selecting games without lots of flash and patterns. Other strategies to lessen the risk of photosensitive seizures can be found here and here.
Tip of the hat to Ian, who suggested that I avoid the word “safe” when describing games that have passed the test. I also will be revising my prior posts to do some rewording.
Gamer’s seizure on live stream
Here’s a reminder that seizures can happen to anyone. A professional gamer known as Lothar had a seizure recently during his live feed while playing Hearthstone on Twitch. Lothar apparently has no history of seizures and the seizure may or may not have any connection to Hearthstone. In updates about his condition and hospital stay, Lothar didn’t mention photosensitive epilepsy nor has he said he’s been advised to limit his gameplay.
For the record, Lothar is also a body builder—he’s obviously a guy who has enjoyed good health and takes good care of himself. Lothar has a large and caring following and has been receiving lots of well wishes as he recovers. Why do I mention this incident here? Viewing the incident (you can find it on YouTube) and seeing how it affected so many fans who care about him reinforced for me the seriousness of seizures and the importance of preventing those that are preventable.
When the Duke and Duchess of Cambridge arrived at their New York hotel this week, it was big news. Did you catch the squeals of delight from the crowd and the flicker of so many cameras flashing? The arrival scene was featured on a number of American news programs.
How it was seen in the UK
This same New York arrival scene was shown in the UK as well—but with an important difference.
Rapid-fire flash photography from the swarm of media creates a strobe-like effect on the image, which is known to trigger seizures in some people. In the US this material is broadcast despite the seizure risk.
But for more than 20 years, TV programs and commercials flashing at frequencies that can provoke seizures have been barred from broadcast in the UK. An exception to the regulation is made for breaking news coverage, where potentially seizure-inducing material is allowed to air if accompanied by a warning. These regulations were put in place after a noodle commercial triggered seizures in several British viewers.
Out of curiosity I tested a video clip of that New York sidewalk scene to see if the flash freqency falls into the category of a seizure hazard. I used an application called the Harding Flash and Pattern Analyzer (below) that assesses video sequences for seizure safety. The clip did in fact exceed flash safety limits for people vulnerable to visually induced seizures. Folks in the UK at least got an on-screen warning, which perhaps gives susceptible viewers a chance to avert their eyes.
What happens when American TV programs are shown in the UK?
TV programs and music videos imported to Great Britain from the US (and other countries) need to be tested first, then modified to comply with the British seizure safety mandate. An engineer in a London post-production studio who does this compliance work shared with me that a popular US crime series had nearly 150 violations of seizure safety guidelines in a single episode. Where is the consumer lobby for seizure-safe TV programming in this country? Anybody?
It’s that time of year when lots of major video games are released, in advance of the holiday shopping season. The marketing build-up has been underway for many months, with snippets of game play shown at industry events and in reviews and cinematic trailers. By testing these snippets I can find out which of these games are likely to create a risk to people vulnerable to visually induced seizures.
The year’s “biggest” games
The editorial staff of GamesBeat (part of tech publication VentureBeat) has already published an “early holiday gaming guide” with its choices for this year’s most eagerly anticipated titles. So far I’ve tested what GamesBeat editors consider the biggest games to be released soon for multiple platforms. In upcoming posts I’ll share test results on their choices for PC-based games and for games exclusively built for Sony, Nintendo, and Microsoft gaming platforms.
Of the 14 multi-platform games, only 3 appear to pose little risk of photosensitive seizures. Images that could provoke photosensitive seizures were found in all the other games.
NOTE: Subsequent testing of The Evil Within (using the final cutscene) on 11/13/2014 revealed that–as shown in this chart–the game fails the seizure safety test. My apologies to anyone who was misled by the original version of this post, in which I listed the game as safe.
To determine whether a video game is safe for individuals susceptible to visually induced seizures, I run them through a photosensitive seizure safety analyzer, the Harding Flash and Pattern Analyzer. The FPA is widely used by producers and networks in the UK—including by the BBC—to ensure seizure safety of all material on broadcast TV. It examines video sequences for very specific and measurable image qualities that researchers have found can trigger seizures:
- rapidly alternating light and dark images (flash/flicker)
- certain stripes and geometric patterns with high contrast
- large areas of very bright (“saturated”) red
- problem images take up more than one fourth of the screen
Visual safety criteria for video sequences are precisely defined in this document used by regulators of broadcast TV in the UK. The criteria were arrived at based on extensive clinical testing.
If the first clip I test of a game fails the safety test, I note that and move on to test the next game. I typically test at least 4 or 5 additional clips of a game if no safety violations are found. I don’t do this testing while actually playing these video games. Instead I work with video clips available online, some of which are official marketing and gameplay trailers; others are gameplay sessions posted by reviewers or fans. I do not test fans’ sequences from games that were modified with other software.
Your results could vary. Games I’ve listed as safe could have seizure-provoking sequences that I was unable to locate. Furthermore, the seizure threshold of individuals is affected by a number of factors including illness, hunger, stress, fatigue, and the player’s menstrual cycle, among others. So a game that seems OK the first time it’s played may trigger a seizure under different conditions.
If the results of a recent study at SUNY at Buffalo are any indication, there are an awful lot of people vulnerable to visually induced seizures who are being told they aren’t at risk. The study showed that testing for photosensitivity using EEG with photic stimulation provides unreliable information. In the wake of these findings, ruling out photosensitive epilepsy–and ignoring the seizure risk from video games–simply on the basis of intermittent photic stimulation results would seem very unwise.
This study–not yet published–by the Buffalo research team found that the test is poorly correlated with vulnerability to visually induced seizures in everyday life. Just 6.2 percent of patients with a history of visually provoked seizures tested positive for photosensitivity.
The standard test for photosensitivity is intermittent photic stimulation—a strobe light flashing at specified frequencies—while hooked up to EEG. Abnormal waves provoked by the photic stimulation are known as the photoparoxysmal response (PPR). (To avoid triggering a seizure during the procedure, the flashing is halted as soon as any of these abnormal waves appear.)
Researchers have known for a long time that many people who test positive never actually experience photic seizures. The Buffalo study confirms this: of 86 patients whose EEG yielded a PPR, just 13 (15.11 percent) reported having experienced visually triggered seizures. What’s new here is the finding that many people who test negative do actually experience these seizures.
The investigators, led by Novreen Shahdad, MD, initiated their study after a patient with a clear history of seizures provoked by electronic screens did not test positive for photosensitivity. “With the increasing popularity of video games and parental concern of their predisposition for seizures,” the authors wrote, “there is a need to identify individuals at risk for PIS [photic induced seizures].”
Shahdad and her colleagues examined a Buffalo EEG database and found 129 patients between 1999 and 2013 who reported seizures triggered by TV, computer use, and video games. Of those patients, a total of 8 tested positive for photosensitivity. Thirty of the 129 patients had reported a history of video game seizures. Of those 30, only one showed a photosensitive response on EEG!
Photosensitivity is defined by researchers as the appearance on EEG, in response to photic stimulation, of certain spike and wave patterns characteristic of epilepspy. Note that the criterion for photosensitivity is not the occurrence of visually induced seizures in everyday life—it refers only to the strobe test.
The study concluded:
“In contrast to the general impression, our study did not find a significant association of a positive response to photic stimulation in patients with photic induced seizures (PIS). This association was seen only in 6.2% of patients with PIS. In addition, PPR on EEG was not associated with statistically significant increase of PIS. Hence we conclude that PPR cannot be used as an isolated predictor for PIS.”
I’ve previously raised questions about diagnosing vulnerability to visually induced seizures soleley on the basis of EEG response to photic stimulation. More study is certainly warranted.
A new definition of epilepsy published this week affirms that photosensitive and other reflex seizures qualify as “real” epilepsy. This clarification may eventually help increase awareness of seizures from video games and other electronic media.
Although reflex seizures have long been included in official classification schemes of epileptic seizures, they don’t fit cleanly into established categories of seizure types and epilepsy syndromes. In neurology training they are typically mentioned only briefly. And typically they are taken too lightly by doctors using the prevailing diagnostic criteria for epilepsy: at least two unprovoked seizures at least 24 hours apart.
Because reflex seizures, by definition, are provoked by specific triggers, there’s confusion and most doctors have been reluctant to diagnose epilepsy in people whose epileptic seizures require an environmental provocation. The authors of the new definition paper acknowledge this:
“Under limits of the current definition, [a] patient might have photosensitive epilepsy, yet not be considered to have epilepsy because the seizures are provoked by lights…People with reflex epilepsies previously have been disenfranchised by the requirement that seizures be unprovoked. The inclusion of reflex epilepsy syndromes in a practical clinical definition of epilepsy now brings these individuals into the epilepsy community.”
Diagnostic criteria under the new definition now include at least two unprovoked or reflex seizures at least 24 hours apart. The new definition also allows an epilepsy diagnosis after a single seizure–either unprovoked or reflex–if there is a high probability of recurrence.
I’ve written previously about the inconsistency inherent in using the criterion of “unprovoked” to diagnose epilepsy in people whose seizures happen only in response to sensory triggers such as flashing light. This thinking (along with the assumption that photosensitive epilepsy is very rare) has led to marginalization of reflex seizures in the research community and among clinicians as well. Marginalization means doctors have been underdiagnosing reflex epilepsy, researchers seeking funding pursue other topics to study, and the public and public policy makers are largely unaware of the public health issue of photosensitive seizures.
The practical clinical definition was developed by a 19-member multinational task force of the International League Against Epilepsy (ILAE), incorporating input from hundreds of other clinicians, researchers, patients, and other interested parties. I’m more than pleased that the ILAE is choosing to make it clear that reflex epilepsy deserves the same respect as other forms of the disease (the new definition paper characterizes epilepsy as a disease rather than a disorder). It’s fortunate that the chair of the ILAE task force that produced the new definition is Robert Fisher, MD, PhD of Stanford, lead author of the 2005 consensus paper describing seizures from visual stimulation as “a serious public health problem.” No doubt Dr. Fisher’s appreciation of the magnitude of the problem was instrumental in ensuring that the task force addressed it.
Not all epileptologists agree with all aspects of the new epilepsy definition–and Epilepsia has given them a voice as well, publishing half a dozen commentaries, all of which are available free online. I contributed a piece as well, providing a patient/family perspective.
Of course, it remains to be seen how long it will take for neurologists to shift their attitudes and diagnostic practices regarding reflex epilepsy. Perhaps the inclusion of reflex seizures in the epilepsy definition will help dispell the idea that reflex seizures are rare.
Gaming fans who object to the concept of seizure-safe games have some major misconceptions about how their favorite games would look after seizure-inducing visuals are removed.
I’ve seen people in online forums threaten to stop their game subscription if the game’s images are made safe. These folks are assuming that making safety modifications to the graphics will mean “neutering” the game experience in a way that ruins their enjoyment. In fact, very minor changes to images, which can be pretty hard to detect, are often all that’s needed.
Thanks to extensive research that defined the characteristics of images that induce seizures, it’s possible to make small changes that interrupt any such seizure-generating sequences. For example, after changes are made to some video frames, the flash interval–more than 3 flashes per second–which can lead to a seizure in people with photosensitive epilepsy, no longer induces seizures.
Want some proof?
NOTE: For those with visual sensitivity, before you click on the upcoming link to side-by-side videos, know that you should be able to view the page safely because the problem images aren’t very large. If you’d prefer not to risk it, you might want to step back farther from your screen or cover the left side of your screen, because that’s where the problem images are.
Now click to see the side-by-side images of a music video running in its original form (with safety violations) and after modifications were made to comply with seizure safety guidelines (in the UK, they’re requirements, not guidelines). The changes are very subtle! Can you find them? As you’ll see in the modified version, even visual sequences that contain some flashes and quick cuts can therefore pass the safety test. Basically, portions of some flashing sequences (9 instances) have been altered or removed, which does little to change the overall viewing experience. Edits to the video that allowed it to be broadcast were done within a single day by London-based post-production firm Vanderquest Limited.
Readers familiar with the Harding Flash and Pattern Analyzer that I routinely use to test video material for seizure safety will recognize the HFPA results shown beneath both versions of the music video. Although the original, uncorrected official version could not be broadcast in the UK due to regulations barring seizure-inducing material from being shown there, it lives on on YouTube.
Imagine these types of edits to the user interface of a video game. Exactly how do they ruin the gaming experience?! Or artistic expression?