A new study has found that many people — especially women — who use virtual reality 3D goggles, experience motion sickness after 15 minutes of use. As the technology becomes more common, wearers will have to adapt to the new sensations the way sailors and astronauts do on the seas and in space.

The condition is known as VR sickness or simulator sickness, and has been recognized for decades, beginning with pilots flying flight simulators. But the new VR headsets are bringing the condition into homes at an ever-increasing rate.

The study involved 18 men and 18 women who tried two different types of motion games using the goggles, and found more than half of them experienced motion sickness. Out of the group who felt nausea, 78% were women.

Our brains use many different ways to determine our body's position in space and how we are moving. Of course, the eyes are the biggest windows on the world, but there are also motion sensors in our ears, and receptors around our body that feel pressure from the ground against our feet, or a chair against our bottoms. Usually, all these inputs to the brain agree with each other to report whether we are sitting, standing, walking, running or falling.

Motion sickness arises when there is a conflict between what the eyes see and what the body feels. The classic case is being inside a boat or ship on a rolling sea. Your eyes don't see the movement of the room because you are moving with it, but your body feels the rolling of the waves. The same thing happens if you try to read a book in a moving car.

In space, astronauts experience the sensation of falling, (which is what weightlessness actually is) but are in what appears to be a stationary ship. Their brains are confused further by a loss of up and down, which completely disappear in orbit. The space program has been faced with this since its inception with about half of all astronauts reporting some nausea or discomfort during the first day in space. The odd part is people who do well with motion sickness on Earth are not always the best in space. Predicting who will get sick is difficult, so everyone takes medication beforehand to be safe. That is also why spacewalks are never done on the first day of a spaceflight, because no one wants to throw up while wearing a helmet and spacesuit.

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Astronauts, like Chris Hadfield, often have to deal with motion sickness. The good news is that it normally passes within a few days. (NASA/Reuters)

It turns out that some poisons affect our organs of balance as well. That's the reason alcohol — which is essentially a poison — produces the off-balance drunken stagger. And, like the drunk, if there is a lot of poison, the body will try to get rid of it by emptying the stomach, making drunkenness, and motion sickness a most unpleasant experience.

Men vs. women

VR goggles produce very powerful motion signals to the eyes, but the body is not experiencing the effect, creating the conflict and discomfort. Why the women were more susceptible than the men in this small study is not well understood, because motion sickness is more complicated than just a conflict between eyes and body.

Another part of the study was to test for body sway while participants were just standing. That is the series of small motions we all make while standing in order to keep our balance.

People come in different body sizes, and women tend to have smaller feet and are generally shorter than men, so some people sway more than others, which might be related.

While motion sickness can be very uncomfortable, eventually, the body does adapt, given enough time. Astronauts get over their motion sickness after about three days in space, and sailors get their "sea legs" after some time on the water.

So perhaps the VR Goggles will have to come with a warning for motion sickness, and suggest taking a break every 15 minutes to let the body adapt. Otherwise, the virtual reality world could become a little too real.