Photosensitive Epilepsy Causes

Seizures with or sensitivity to light. photosensitivity. In some patients with epilepsy when they see flashing lights or a pattern to make seizures more called "photosensitive epilepsy" is encouraging. For example, a photosensitive screen or a flashing light. Animation. Such as video games or computer screen color TV with multi-colored alternates. It's not that these lights will make time fly. There are also other factors such as the frequency of the light, which is generally in the range of 5-30 Hz stimulation frequency, brightness, contrast of the background light. The distance between the view and the light source. Length of light.

Photosensitive Epilepsy Causes

• Flashing light
• Bright, contrasting patterns such as white bars against a black background
• Flashing white light followed by darkness
• Stimulating images that take up your complete field of vision, such as being very close to a TV screen
• Certain colors, such as red and blue

Some specific examples of situations or events that can trigger seizures in people with photosensitive epilepsy are:

• Nightclub and theater lights, including strobe lights
• TV screens and computer monitors
• Flashing lights on police cars, fire trucks, ambulances, and safety alarms
• Visual effects in movies, TV shows, and video games
• Malfunctioning fluorescent lights and moving escalators
• Light viewed through a fast-moving ceiling fan
• Sunlight viewed through slanted blinds or stair railings
• Sun shining through tree leaves or reflecting off water
• Bold, striped wallpaper and fabric
• Cameras with multiple flashes or many cameras flashing at the same time
• Fireworks

Also, people with photosensitive epilepsy may be at increased risk for a seizure if they are:

• Tired
• Intoxicated
• Play video games too long without a break

What Photosensitive Epilepsy?

What Photosensitive Epilepsy?  - Epilepsy is a brain disorder that causes recurrent seizures (more than two). A seizure is caused by abnormal electrical activity in the brain.

Epilepsy may be the result of:

Irregularity in the wiring of the brain

Umbalance of neurotransmitters (chemical messengers in the brain)

Combination of these factors

In photosensitive epilepsy, genetics also plays a role.

About one in 100 people in the U.S. have epilepsy. About 3% to 5% of those people have photosensitive epilepsy.

Children and adolescents aged 7 to 19 are more likely to have photosensitive epilepsy. Girls are affected by the condition more often than boys. But boys tend to have more seizures. That's probably because they spend more time playing video games, a common seizure trigger.

 

Photosensitive Epilepsy Symptoms

People with PSE experience epileptiform seizures upon exposure to certain visual stimuli. The exact nature of the stimulus or stimuli that triggers the seizures varies from one patient to another, as does the nature and severity of the resulting seizures (ranging from brief absence seizures to full tonic–clonic seizures). Many PSE patients experience an “aura” or feel odd sensations before the seizure occurs, and this can serve as a warning to a patient to move away from the trigger stimulus.

 


The visual trigger for a seizure is generally cyclic, forming a regular pattern in time or space. Flashing lights or rapidly changing or alternating images (as in clubs, around emergency vehicles, in action movies or television programs, etc.) are an example of patterns in time that can trigger seizures, and these are the most common triggers. Static spatial patterns such as stripes and squares may trigger seizures as well, even if they do not move. In some cases, the trigger must be both spatially and temporally cyclic, such as a certain moving pattern of bars. Several characteristics are common in the trigger stimuli of many PSE patients.

The patterns are usually high in luminance contrast (bright flashes of light alternating with darkness, or white bars against a black background). Contrasts in color alone (without changes in luminance) are rarely triggers for PSE. Some patients are more affected by patterns of certain colors than by patterns of other colors. The exact spacing of a pattern in time or space is important and varies from one individual to another: a patient may readily experience seizures when exposed to lights that flash seven times per second, but may be unaffected by lights that flash twice per second or twenty times per second. Stimuli that fill the entire visual field are more likely to cause seizures than those that appear in only a portion of the visual field. Stimuli perceived with both eyes are usually much more likely to cause seizures than stimuli seen with one eye only (which is why covering one eye may allow patients to avoid seizures when presented with visual challenges). Some patients are more sensitive with their eyes closed; others are more sensitive with their eyes open.