A
photosensitive seizure is any seizure that is triggered by light, usually flashing light. Any source of flashing light can be a potential hazard, including light filtering through
trees as you drive down a road,
television sets, computer monitors, and
strobe lights. Seizures can also be triggered by patterns of stationary striped lines.
The
seizures that result are usually
generalized tonic-clonic seizures.
These seizures occur primarily in
women, show a strong hereditary relationship, in many cases (roughly 50%) people who have them also have parents who experienced them as a child. 88% of epileptics who are trigger by lights experienced
childhood absence seizures or
myclonic seizures. The tendency toward these seizures diminishes in most patients during the
teen years.
In most cases (90%), the
stimulation of only one
eye is far less apt to produce a seizure, thus, those who have
photosensitive seizures may be able to control their reactions to stimuli by covering one eye.