Concern about the potential effects of screen time on health is common, especially regarding seizures. Many wonder if prolonged exposure to screens could lead to such neurological events. This article clarifies how visual stimuli from screens might act as triggers for specific types of seizures.
Understanding Photosensitive Seizures
A seizure results from a sudden, uncontrolled electrical disturbance in the brain, leading to temporary changes in behavior, movement, or consciousness. While many factors can contribute to seizures, photosensitive epilepsy is a specific type triggered by visual stimuli. This condition is relatively rare, affecting approximately 3% to 5% of individuals diagnosed with epilepsy. It is more commonly observed in children and adolescents, developing between the ages of 7 and 19.
Photosensitive epilepsy is characterized by sensitivity to certain light patterns, particularly flashing or flickering lights and high-contrast visual patterns. Not everyone with epilepsy has this sensitivity; an underlying predisposition, often genetic, is involved. While visual triggers are specific to this form, the resulting seizure can be of various types, with generalized tonic-clonic seizures being common.
How Screen Time Can Be a Trigger
For individuals with photosensitive epilepsy, certain screen content characteristics can act as triggers. Rapidly flashing or flickering lights are primary culprits, especially those flashing between 3 and 60 times per second (hertz), with frequencies between 16 and 25 hertz being most likely to trigger a seizure. High-contrast patterns, such as bold stripes or checkerboards, and intense brightness changes can also provoke a response.
The intensity and frequency of these visual stimuli are key factors. Certain video games, fast-paced video content, or animations with flashing elements can present these problematic visual patterns. While modern flat-screen displays (LCD or TFT) generally have high refresh rates and are less likely to flicker, the content displayed can still contain triggering elements. Viewing against a dark background or being very close to a screen, where the visual effect fills a large portion of the field of vision, can also increase the risk.
Minimizing Risk and Protecting Yourself
Individuals with photosensitive tendencies or a family history of photosensitive epilepsy can adopt several strategies to reduce their risk while using screens. Maintaining a safe viewing distance is important; for instance, sitting at least 2 feet (60 cm) from a computer monitor and 8 feet (2.4 meters) from a television can help reduce the impact of visual stimuli. Adjusting screen settings, such as reducing brightness and contrast, can also be beneficial.
Adequate room lighting is a practical measure, as watching screens in a well-lit environment reduces contrast between the screen and surroundings. Frequent breaks from screen use are also advisable, helping to mitigate eye strain, fatigue, and potential sleep deprivation, which can lower the seizure threshold for some individuals. If content with known triggers, such as rapid flashes or patterns, cannot be avoided, some devices offer accessibility settings to mitigate effects. Consulting a healthcare professional is recommended for personalized advice if concerns about personal risk or symptoms related to screen time exist.