Ills triggered by films may suggest the need for an eye exam
THURSDAY, April 8 (HealthDay News) -- The new crop of 3-D movies hitting theaters are making some people sick -- literally.
It's not the alien creatures bleeding off the screen or half-eaten humans spit out in your direction by fierce dragons. It's just the way 3-D plays tricks on your brain, mimicking symptoms of motion sickness.
The problem, if you have one, may lie in your head and, in particular, your eyes, experts note.
An unlucky (or lucky, depending on your point of view) 5 percent of the population have such bad eye coordination they can't perceive 3-D at all. But if these people decide to plunk down $20 for Avatar or Alice in Wonderland, at least they won't get a headache.
"In 3-D movies, your eyes have to be working together as a team perfectly. You have to have equally clear images in both eyes," explained Dr. James J. Salz, spokesman for the American Academy of Ophthalmology and clinical professor of ophthalmology at the University of Southern California in Los Angeles. "Then you will get the fusion of the two images."
Getting the 3-D effect involves using two different cameras projecting two images on top of each other to create depth perception. Salz's former partner, Dr. Julian Gunzberg (now deceased), developed the original 3-D technique used in House of Wax with Vincent Price.
An estimated 30 percent of moviegoers have enough eye coordination to see 3-D, but only with a struggle. These are the ones more likely to get headaches and eye fatigue while watching 3-D on the big screen, said Jeffrey Anshel, an optometrist with VSP Vision Care and the principal of Corporate Vision Consulting in Encinitas, Calif.
"The problem comes in with people who have 3-D vision but have a weak fusional mechanism," Salz explained. "Your eyes are having to work harder. The brain is sending extra impu
All rights reserved