A talk with ChatGPT: Displays and Seizures

Me

I know people who have had epileptic seizures and one close friend who had specifically playing Age Of Empires in a closed dark room on a cheap laptop that probably used PWM.

Can you do a deep research about how sleep, tiredness, room how much lit, OLEDs vs. IPS, displayws with PWM vs. without PWM and other factors affect such seizures.

Thanks for the detailed background. To tailor the research to your needs, could you please clarify a few points:

1. Are you interested only in how these factors affect people who already have a diagnosed epilepsy condition, or also how they might trigger seizures in people without prior diagnosis?
2. Do you want the research to focus specifically on video game usage (like Age of Empires), or include general screen/device use as well?
3. Should I include research on preventive measures or mitigation techniques (like screen filters, room lighting tips, etc.)?

Once I have this, I'll get started right away.

1. WIthout prior diagnosis.
2. ALl use cases.
3. Yes.

Please do all these in as much details as possible.

ChatGPT Deep Research

Understood. I'll begin a deep dive into how factors like sleep, fatigue, lighting, screen technology (OLED vs. IPS), and PWM (pulse-width modulation) contribute to seizures in individuals without a prior epilepsy diagnosis, across all screen use cases (not just gaming). I'll also include research on effective prevention and mitigation strategies.

I'll let you know once the research is ready for your review.

Screen Use and Seizures in Undiagnosed Individuals

Photosensitivity - a genetic hypersensitivity of the visual cortex - can cause provoked seizures in response to certain visual stimuli even in people without a prior epilepsy diagnosis. Common triggers include flickering lights, high-contrast patterns, rapid color changes, or intense visual stimulation from screens. Typically, flashes or patterns at 10-25 Hz (especially ~15-20 Hz) are most epileptogenic. Other key factors increase risk, often in combination. For example, strenuous gaming or prolonged screen use can induce fatigue, which lowers seizure threshold. Similarly, viewing high-intensity flashes or fast-moving images in a dark room greatly increases contrast and field of view, raising risk. The classic 1997 “Pokémon” incident illustrates this: a 4‑second, 12.5 Hz red-blue strobe scene on TV triggered seizures in nearly 700 viewers.

Photosensitive seizures typically manifest with generalized symptoms (e.g. staring, myoclonus, tonic-clonic convulsions), though focal/occipital seizures can occur (often with visual aura). In many cases the seizure-prone individual was previously undiagnosed; indeed, most reported cases of video-game-induced seizures were first seizures. An estimated ~1-8% of healthy children show photoparoxysmal EEG responses to strobe lights (indicating photosensitivity), yet may have never had a clinical seizure. In such people, an unusually intense visual trigger (e.g. fast game flashes, strobe) can produce a one-time seizure or EEG discharge despite no history of epilepsy.

Sleep Deprivation and Fatigue

Lack of sleep and mental exhaustion are potent seizure facilitators. Sleep deprivation alone can dramatically lower seizure threshold (increasing interictal spikes and seizures in predisposed brains). In the context of gaming or work, staying up late or playing for hours without rest combines fatigue and intense stimulation. Case series report that factors like excitement, fatigue, sleep deprivation, alcohol, or drugs markedly contribute to screen-triggered seizures. Recommendation: Ensure adequate rest and breaks. Avoid gaming or heavy screen use when overtired or just after waking. Clinically, people are advised to take frequent breaks and stop if feeling sleepy or dizzy.

Room Lighting and Contrast

Ambient light level modulates seizure risk. A dark room (high contrast between screen and surroundings) amplifies the apparent brightness and area of flicker, making a given screen more provocative. Experts therefore recommend viewing screens only in a well-lit environment. For example, one Epilepsy Action guide advises keeping a lamp on by the TV or monitor and avoiding dark rooms. Similarly, the Epilepsy Foundation suggests “watch television in a well-lit room to reduce the contrast between light from the set and light in the room,” and to “sit as far back from the screen as possible”. Bright ambient lighting means any flicker or flash occupies a smaller fraction of the visual field and appears less intense, which can prevent a seizure even if the screen content is provocative. Recommendation: Add diffuse room lighting (lamps or overhead lights) whenever using a screen intensively; never play games or watch video in total darkness.

Display Technology, PWM, and Flicker

Different screen types and settings can affect flicker and brightness dynamics. High-refresh, flicker-free displays are safest. Modern flat-panel LCD/LED monitors typically refresh at ≥60-120 Hz and often use constant-current reduction (CCR) dimming, which produces no perceptible flicker. Many manufacturer “flicker-free” monitors use analog dimming at all brightness levels. By contrast, OLED displays (common in smartphones and high-end TVs) typically dim by rapid on/off PWM pulses (~240-480 Hz). Although these rates exceed human perception (critical flicker fusion), extremely sensitive individuals can still be affected by OLED's pulse-width modulation at low brightness. Older CRT televisions and monitors ran at ~50-60 Hz and had visible scan flicker; these are virtually obsolete but used to be a common trigger. Active-shutter 3D glasses (used in some VR/3D systems) produce 60 Hz flicker per eye and can be provocative if viewed without 3D content.

Table 1. Display technology and flicker characteristics. Modern high-refresh screens and small displays occupy less field of view, reducing trigger risk, whereas large or low-refresh displays increase it.

Citations: display summaries from Epilepsy Action and recent guidelines; CRT risk from Epilepsy Action.

Blue light (short-wavelength light from screens) does not directly induce seizures, but it can suppress melatonin and worsen sleep. Many recommendations suggest blue-blocking filters primarily for eye strain and sleep, with only anecdotal benefit for seizures. However, some studies show deep-blue tint (Z1) glasses can reduce seizure likelihood by filtering red light, which is more epileptogenic.

Flicker Rate, Refresh Rate, and Visual Patterns

The rate of flicker is critical. Multiple sources agree that flashes at ~10-25 Hz are most likely to trigger seizures. Very slow flashes (<3 Hz) or very fast flicker (>60 Hz) are less risky for photosensitive individuals. Importantly, large-area flashes (filling much of the visual field) and high contrast increase risk. Conversely, small or peripheral flickers (e.g. in a corner of the screen) are safer. Even non-flashing patterns (stripes, geometric designs) can provoke seizures if they produce alternating dark/light fields when moved on screen. Rapidly moving images or high-contrast color changes (for example, flashing red/blue bars or fireworks effects) are especially hazardous.

Modern content guidelines (e.g. WCAG 2.0/2.1) mirror these findings: they limit flashing to <3 flashes/second, or above 3 Hz require limiting area, contrast and color cycles. Consumer electronics likewise often include “flicker-free” or “low motion blur” modes: care is needed, as some motion-enhancement features (backlight strobing or black-frame insertion) deliberately introduce flicker. Recommendation: Avoid videos, games or web content known to contain high-frequency strobe or rapidly alternating scenes. When possible, enable in-game or OS accessibility modes that disable flashing effects (e.g. turn off camera flash effects, strobing lights, auto-play GIFs/videos).

Device Size and Viewing Distance

The visual angle of the stimulus strongly influences risk. Larger screens (big TVs, dual monitors) or closer viewing distances place more flicker in the field of vision. By contrast, small handheld devices or watching from across the room are safer. Epilepsy Action advises viewing from at least 2-3 times the screen's width (roughly ≥2 meters for a typical TV). Smaller displays (tablets, phones) inherently cover less area and are less likely to trigger photosensitive seizures. Recommendation: Use smaller screens if sensitive. Sit as far back as practical. Some experts even suggest covering one eye if you encounter an unexpected flash (monocular viewing halves stimulus area).

Highly Stimulating Content (Games and Video)

Certain visual content is intrinsically provocative. Fast-paced video games, especially with flashing explosions, strobes, or rapid scene changes, are common culprits. The classic case: the 1997 Pokémon cartoon “pallette swap” (rapid red/blue flashes) triggered seizures in hundreds of viewers. Likewise, “shimmering” effects (glitter, flickering water) and alternating color patterns can provoke seizures in susceptible people. Motion intensity matters too: very bright flashes, alternating colors (especially red/blue), and high-contrast stripes are known triggers. On the other hand, purely dark or smoothly lit scenes (even if dynamic) are rarely problematic by themselves.

Because content matters more than the device, modern experts note that watching a movie or playing a game is not inherently dangerous - it's the visual sequence that counts. The FAQs affirm: “TV, videogames, virtual reality and 3D images are not in themselves provocative, but their content can be.”. Some content creators now use tools (Harding Flash Analyzer, WCAG guidelines) to ensure flash patterns stay within safe limits.

Photosensitivity Without Epilepsy Diagnosis

People with unrecognized photosensitive predisposition may never have an unprovoked seizure but can still suffer a triggered seizure when conditions align. Cases have been documented of otherwise healthy individuals having their first-ever seizure while gaming or watching flashing content. For example, a 58-year-old man with no epilepsy history had a tonic-clonic seizure while playing video games at close range. His condition (and others like it) is called idiopathic photosensitive epilepsy; it may manifest only when provoked by strong visual stimuli. These individuals are often normal between episodes.

Subclinical responses are also possible: many people exhibit a photoparoxysmal EEG response (PPR) to flashing lights without any clinical seizure. That is, an EEG may show epileptiform spikes during a strobe test even if the person never convulsed. Thus, screen flicker can elicit brief neural discharges or minor seizure-like events (eye jerks, altered vision) that go unnoticed. If someone briefly blacked out, convulsed, or had an unexplained fall during intense gaming or strobe exposure, it may have been a provoked seizure. In summary, first-time or isolated seizures triggered by screens can occur in photosensitive individuals who would otherwise appear normal.

Case Studies and Research

Several studies have characterized screen-induced seizures. A 1994 JNNP review described 15 patients who seized during video games; 9 of 15 had their first seizure while gaming. Non-photic factors (excitement, fatigue, sleep loss) were emphasized as precipitants, especially in patients without classic photosensitivity on EEG. In that series, most patients (≈70%) were found to have idiopathic generalized epilepsy and half of those had juvenile myoclonic epilepsy - conditions known for photosensitivity. Two children even “self-induced” seizures by triggering screen flicker.

On the other hand, an epidemiological study (Chuang, 2006) on MMO games noted that heavy gamers sometimes experience seizures as part of internet-addiction syndromes. Reports from emergency services have described adult “video game epilepsy,” often in male adolescents with prior exhaustion. These real-world cases reinforce that anyone - child or adult - can be sensitive if exposed to a potent visual trigger.

Neurologically, photosensitive seizures involve hyper-synchronization of occipital cortex in response to rhythmic visual input. EEG studies show generalized spike-wave or occipital spikes in response to flicker. In susceptible individuals, these discharges can quickly spread to cause a full seizure. Genetic studies indicate strong heritability of photosensitivity. For example, monozygotic twins often both show photoparoxysmal responses, and PSE commonly co-occurs in families with generalized epilepsies.

Age, Gender and Genetic Factors

Photosensitivity is most common in children and adolescents. In fact, first light-induced seizures almost always occur before age 20. Many affected individuals “outgrow” this sensitivity by early adulthood - roughly half of childhood cases lose their photic EEG response later on. Younger brains appear more excitable to flicker, perhaps due to developmental factors.

Gender differences are noted but somewhat conflicting. Some sources report that girls have a higher predisposition (60% vs 40% in boys) to photosensitivity, though boys experience more game-related seizures (possibly due to higher gaming rates). Other data indicate women are twice as likely to have photosensitive epilepsy as men. Regardless, both sexes can be affected.

Genetically, photosensitivity tends to run in families. A child with a photosensitive seizure often has relatives (parent, sibling) with epilepsy or an abnormal EEG response. Specific epilepsy syndromes (e.g. juvenile myoclonic epilepsy) have very high photosensitivity rates. The recent expert review notes “there is a genetic risk, which is outgrown in about half” of affected individuals. In practice, this means a person with one photosensitive seizure should be monitored long-term, as they may later develop unprovoked seizures (meeting the definition of epilepsy).

Recommendations and Mitigation Strategies

Based on current evidence and guidelines, the following strategies are recommended to prevent screen-triggered seizures in susceptible individuals:

• Ambient Lighting: Use bright, diffuse room lighting. Keep lamps on and avoid darkened rooms when using screens. Even simple overhead lights or a desk lamp by the monitor significantly reduce contrast.

• Screen Settings: Lower brightness and contrast of monitors and TVs to the minimum needed for comfortable viewing. High brightness amplifies flicker effects. Many devices offer “night mode” or blue-light filter settings - these primarily improve sleep but also slightly reduce overall intensity. Use “flicker-free” monitors (advertised by manufacturers) or those that employ analog dimming. Avoid screens with known PWM dimming, or at least keep brightness ≥50% (PWM duty cycle more even). If possible, choose high refresh-rate displays (≥100 Hz); higher refresh reduces perceived flicker and latency.

• Viewing Habits: Maintain distance - sit at least several feet/meter from the screen (Epilepsy Action: ≥2 meters or 3× screen width). Use smaller screens when possible (mobile or tablet) rather than large TV screens. Play games in windowed mode instead of fullscreen, and avoid projecting onto big screens. Take regular breaks: follow the 20-20-20 rule (every 20 minutes look 20 feet away for 20 seconds) or simply rest eyes every hour. Do not use screens when overtired or after missing sleep, and avoid all-nighters. Limit continuous play duration; many experts recommend no more than 1-2 hours at a stretch and then a break.

• Content Control: Disable auto-play of videos/GIFs on social media and websites. Encourage game and software developers to include “seizure-safe” modes (e.g. remove flashing backgrounds, strobe). View content with known warnings (e.g. video apps and BBFC film ratings for PSE). Consider installing browser extensions or apps that analyze/slow down flashing content (e.g. HardingFPA filters or epilepsy mode browsers).

• Protective Eyewear: Some patients benefit from tinted lenses. Blue-tinted (Z1) lenses filter out red light, reducing one of the most provocative wavelengths. Dark or polarized glasses can cut overall brightness. These measures are supplemental and not foolproof, but worth trying under medical guidance. Note: colored lenses may impair color recognition, so use with caution (e.g. not while driving).

• Environmental Controls: Cover one eye if a flash is encountered unexpectedly - this immediately halves the stimulus. Use anti-glare screen filters and position screens to avoid sunlight or overhead lights reflecting on them. In group settings (classrooms, gaming events), encourage hosts to avoid strobe lighting.

• Lifestyle: Maintain regular sleep and stress-reduction practices. Adequate nutrition and hydration also support a higher seizure threshold. Since co-factors like alcohol and stimulants increase photosensitivity, avoid excessive caffeine or alcohol while planning intensive screen use.

• Monitoring and Screening: If an individual reports visual auras, unusual sensations, headaches, or brief blackouts associated with screen use, seek medical evaluation. An electroencephalogram (EEG) with intermittent photic stimulation can test for photosensitivity. Keeping a symptom diary (logging triggers, screen times, pre-seizure feelings) can help physicians identify patterns. For known susceptible individuals, consider periodic screening (especially in childhood, when sensitivity is highest).

Table 2. Preventive Strategies and Their Rationales

Aspirational goal: Screen designers and content providers should follow accessibility guidelines (WCAG, ITU-R BT.1702, Ofcom) to minimize risk in all media. For users, the best protection is a combination of environmental adjustment and vigilance. If a screen-use episode provokes any alarming symptom, stop immediately and seek evaluation.

Sources: This report synthesizes clinical reviews, case series, and expert guidelines from the epilepsy literature. In particular, public health advisories and peer-reviewed analyses emphasize the multi-factorial nature of screen-provoked seizures and recommend layered preventive measures.