Photosensitive Epilepsy :: Biology Essays Research Papers

Photosensitive Epilepsy A 17-year-old girl falls to the floor. She was playing the video game Dark Warrior. Her father, who is a video game repairman, fears that she has been electrocuted. The girl has fanatically played one game after another for years, and nothing like this has happened before. She is rushed to the hospital where doctors determine that she has had an epileptic seizure. An unusual bright flashing sequence in the game seems to have set her off (1) . Two 13-year-old girls are playing Super Mario Brothers. When the pace of the action picks up in the third straight hour of their play, one girl starts to shake and, for three minutes, has nonstop epileptic seizures (1) . Six hundred eighty five Japanese people ranging in age from five to fifty-eight suffer spasms, convulsions, vertigo, and breathing difficulty while watching a colorful cartoon program. Doctors determine that most were suffering from epileptic seizures induced by a flashing white light sequence during the show (2) . In the United States, there are close to one million people with epilepsy-- about 1 in 200 people around the world have epilepsy. For most of those people, video game playing and watching television are not a risky activities. The flashing patterns of certain games and television shows trigger epileptic seizures in only 5% of epileptics (1) . Photosensitive epileptics have with a peak age of onset of 10-14 years, are mostly woman, and experience a decline in the photosensitivity after 25 years of age (3) . In normal brain function millions of tiny electrical charges pass from nerve cells in the brain to all parts of the body. In patients with epilepsy, this normal pattern is interrupted sometimes by sudden and unusually intense bursts of electrical energy, which may briefly affect a person's consciousness, bodily movements, or sensation (4) . During a seizure, nerve cells in the brain fire electrical impulses at a rate of up to four times higher than normal. This causes a sort of electrical storm in the brain (5) . A pattern of repeated seizures is referred to as epilepsy (4) . Seizures cause different physical effects depending on which parts of the brain are involved and how far the signals fan out. Some people have violent seizures that knock them to the floor unconscious and twitching. Others experience less severe seizures that may only blank them out for a few seconds or more.