The Connection Between Epilepsy & Hypersensitivity

Epileptic seizures occur when the brain misfires strong electrical signals that cause the affected individual to lose consciousness and the body to convulse. Seizures may be triggered by light hypersensitivity or photosensitivity in some individuals. Photosensitivity may occur in those individuals afflicted with generalized epilepsy and it occurs in nearly 90 percent of all children with juvenile myclonic epilepsy.

Significance

• According to epilepsy.com, about 3 to 5 percent of those individuals with epilepsy may be hypersensitive to flashing light. In these individuals flashing lights may trigger a seizure. Photosensitivity occurs more commonly in girls, but boys experience more light-triggered seizures due to increased video game playing.

Types

• Many different types of flashing lights in the environment may trigger seizures in hypersensitive individuals. Sources of flashing lights may include sunlight when peaking between trees and other structures, flickering light bulbs, TV images and video games. Some individuals may also be sensitive to visual patterns with high contrast such as stripes, checkerboards and grids.

Effects

• When an individual with epilepsy and photosensitivity sees flashing lights of contrasting patterns, her brain may respond by producing electrical discharges that cause a seizure. Initially, the person may experience strange sensations and body jerks. Continued exposure to the lights may result in a seizure.

Identification

• Physicians use EEG testing in conjunction with strobe light exposure to determine if patients exhibit photosensitivity. During the test, hypersensitive patients typically experience body jerks and in some cases even a seizure. Prior to testing, most patients do not realize that they have photosensitivity.

Considerations

• Not all individuals with epilepsy experience hypersensitive reactions to light and not all individuals who have seizures as a result of photosensitivity have epilepsy. Those individuals with epilepsy will most likely be prescribed anti-epileptic medications to control seizures. Anyone with seizure-producing photosensitivity should avoid visual triggers as much as possible.

Expert Insight

• According to epilepsy.com, certain factors increase the risk of a light-triggered seizure. The closer an individual sits to the light source, the more the risk. Also, saturated red color tends to be more likely to trigger a seizure. Some people with extreme sensitivity need to wear blue lenses when driving to reduce the risk of having a seizure when looking at red stoplights and the red taillights of other vehicles.

Epidemic Occurrence

• According to epilepsy.com, on December 16, 1997, nearly 700 children in Japan were taken to the hospital after having seizures while watching a certain episode of the Pokemon cartoon. During the cartoon, red and blue lights flashed for four seconds during the launch of a rocket.