Blog #14: Photosensitive Epilepsy

(This blog was originally posted on December 5, 2011)

 

          People can have seizures when exposed to certain stimuli. They are genetically predisposed to this phenomenon. There is a vivid scene in the recent movie release, Twilight Saga: Breaking Dawn, Part 1, in which bright lights in red, black, and white flash across the screen. Audience members in various cities across our country are reported to have suffered seizures while watching that scene. One man in Utah was said to be mumbling and blinking his eyes according to his wife. At least one person was taken by paramedics to an emergency room. In 2009 viewers suffered convulsions watching the movie Avatar. It is not known if any of these individuals ever had prior seizures.

Photosensitive epilepsy is a form of reflex epilepsy—seizures provoked by a specific stimulus, such as strobe or flickering lights. Some people find exposure to red-colored flickering lights, like the flashing red color in the Twilight film, induces seizures. Natural light—such as sunlight through leafy trees while driving, or waving a hand with spread fingers in front of a light source—can cause a seizure. Other examples include reading that induces certain eye movement patterns, or sound patterns heard in specific musical passages. Even anticipating, or thinking of eating food (this is rare), is known to cause reflex-type seizures.

Seizures while playing video games or watching TV is a recognized phenomenon. These events can consist of suspension of activity during which the mind is blank for several seconds to minutes followed by confusion or a genuine convulsion. Some people will jerk just one or more limbs, called myoclonic jerks. Electroencephalogram (EEG) laboratories routinely assess for this sensitivity to flickering lights. Patients are exposed to strobe lights during the EEG to test for abnormal paroxysmal patterns.

Those susceptible to reflex seizures should avoid exposure to that particular stimulus. If this fails to prevent seizures, then neurologists can prescribe anticonvulsant medications.

 

 

 

Lance Fogan, M.D. is Clinical Professor of Neurology at the David Geffen School of Medicine at UCLA. DINGS is his first novel.