An epileptic seizure is a sudden and brief surge of electrical activity in the brain, due to abnormal, excessive or synchronous neuronal activity. Seizures are a symptom of many diseases of the brain, collectively called epilepsy. The most common type of seizure is convulsive, with the body muscles contract and relax rapidly and repeatedly, thus resulting in an uncontrolled shaking of the body. In addition, the generalized seizures involve a loss of consciousness. In a complex partial seizure a person may appear confused or dazed and cannot respond to questions or direction.
People with a specific condition, called photosensitive epilepsy (~3-5% of people with epilepsy) may suffer a seizure when frequency of flashing light of computer screens (or monitors), or of content being rendered, is in the range of 3 to 50 flashes per second. Furthermore, people are even more sensitive to red flashing than to other colors.
Video explanation of photosensitive epilepsy:
Web Page Evaluation Tool
- Trace Center's free Photosensitivety Epilepsy Analysis Tool (PEAT)
- Trace Information on Photosensive Epilepsy
Bibliography
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