Here at Tech Insider, we've been testing a lot of virtual reality (VR) products lately.
And while headsets like Oculus Rift are entertaining and amazing us, they're also making us feel sick.
Many people report feeling nauseous and seasick after trying VR, and some say that their head and eyes hurt.
Marty Banks, a professor of optometry and vision science at the University of California, Berkeley, said this is a common problem. His lab studies the effects that emerging technology, screens, and virtual reality headsets have on our eyes.
He told Tech Insider these sickening feelings and headaches are due to what researchers call the vergence-accommodation conflict.
Convergence is what happens when both of your eyes look at an image to prevent you from seeing double, and accommodation is what your eyes do to keep that image from looking blurry.
Banks says these two processes are linked in the brain so we can see the world around us properly. They have to work together in order to focus on images at different distances.
"On these displays, you have to break that linkage," he says. "You have to accommodate to one distance and converge to another distance. And we believe that need, to kind of break the normal coupling, is what leads to the discomfort."
This same phenomenon happens when people watch 3D movies, too.
For now, Banks says, many filmmakers make sure they don't move characters in and out of the screen too fast so it doesn't trigger the vergence-accommodation conflict.
Researchers are working on ways to design VR so it could trick your eyes into thinking there's no conflict, but they're not going to be on the market anytime soon.
For now, a little nauseousness and discomfort is the price we have to pay for this revolutionary, immersive technology.
