Did you know that during a flight that experiences turbulence, more than 25 percent of the passengers will experience symptoms of motion sickness? And a fairly big proportion of them will likely throw up? Many of us are used to the symptoms of motion sickness as we travel - nausea, sweating and headaches - but we'll pop an anti-nausea pill, take some ginger or just wait it out, because it's an inevitability.
Now Sony's PlayStation VR is promising to take the tech mainstream but more and more people are reporting that they experience symptoms of motion sickness while they're wearing VR headsets. When you've forked out a fortune for the tech and most likely bought it for entertainment or educational purposes, it's not as easy to ignore your symptoms or just hope they pass.
We wanted to explore why we experience motion sickness when we wear VR headsets, who feels the symptoms the most and what tech companies are doing to address the problems. This is a big deal because VR headsets may be used mainly for gaming and light entertainment for now, but if VR ends up playing a huge role in everything from on-the-job training to education to healthcare as it's expected to, it needs to be as comfortable, easy-to-use and non-discriminatory as possible.
What is motion sickness?
There are actually a range of theories as to why people experience motion sickness. I spoke with Professor John F. Golding, from the faculty of science and technology at the University of Westminster, London. He specialises in motion sickness.
He explained that there are all kinds of symptoms of travel sickness, from nausea and vomiting (the two most common) through to sweating, increased salivation, warmth, dizziness, drowsiness, headache, loss of appetite, decreased sensitivity to odours and many more, less frequent ones. He also told me motion sickness was actually used as a form of punishment and even therapy in the past which will make anyone who experiences it acutely wince in pain right now.
Golding explained that when we're talking about visual mismatches, as we experience in virtual reality, the oculomotor symptoms are sometimes the worst. That's eye strain, difficulty focusing and headaches.
I asked Golding why we experience motion sickness and he told me it can all be boiled down to a sensory conflict or mismatch, which essentially means one sense is telling us one thing—your eyes say you're walking around a virtual world—and another sense tells you another—your body tells you you're sat down.
Of course, it's much more complicated than that. There's a lot of interesting science going on here that you should read up on if you're interested. But it essentially boils down to a conflict between either vestibular (your balancing system in your inner ear), visual (what you can see) or kinaesthetic (movement) inputs.
I asked Golding what's specifically going on with virtual reality then, because although it's similar to being on a boat or plane, it's also different in many ways. He explained that there are a number of reasons why VR can bring about the symptoms of motion sickness.
"As you move your head with a VR headset on," he said, "the advanced sensors in the headset will know you're moving it and refresh the screen accordingly to make it move the right way—this ensures what you're seeing is as real as possible. For example, you move your head to the left and the screen shifts right. But, it can't do it as fast as it needs to in most cases. It needs to do it in 5 to 10 milliseconds and if there's any kind of lag, it can cause sensory conflict, even if it seems real enough to you consciously."
Although lag is probably the most common reason why people experience motion sickness while using VR, there are other considerations at play too. There's the sensory conflict if you're hurtling through space and yet sat down—you may have experienced this at the cinema—and there's also the fact VR headsets are so close to you.
Golding told me some people experience the eye straining symptoms of motion sickness because when we use a VR headset our eyes have to physically angle in a bit to compensate with it being strapped to our faces. Not only can this strain our eyes, but it causes even more of that vom-inducing conflict. Your eyes know the screen is SO close, but you're looking at a scene that's meant to be really far away.
When I asked why we get motion sickness in the first place, Golding said there are a number of theories. But if you're looking for a big, overarching 'why', then blame evolution. He said it could be a very ancient mechanism that ensures we don't die if we get poisoned. Your body sees senses aren't matching up, assumes you've ingested a toxin and makes you want to get rid of it immediately.
Of course it doesn't work as well as it should, because it usually takes a good ten minutes at least for me to throw up on a boat, by which time I'd have presumably already died from the toxins. So thanks, evolution!
Why do some people get it and others don't?
New studies suggest for every one man who gets motion sick, four women do
According to Golding, there's no definite figure about how many people are likely to feel symptoms of motion sickness when they use virtual reality technology just yet. But considering around 25 percent of people on a flight might experience symptoms during low altitude air turbulence and a third in coach journeys, we might expect it to wipe out a huge chunk of the population if the tech doesn't change soon to compensate.
With certain stimuli, most of the population can actually experience motion sickness. Which is why some people don't tend to get it all the time, yet are set off by certain experiences.
The two biggest predictors are gender and age. Women are more likely to experience motion sickness, Golding told me in a study of sea sickness there's a 5:3 female to male risk of vomiting. And not only are we likely to experience it more, but symptoms can be more acute. Yay for being female!
Although that's the ratio for sea sickness, newer studies suggest the ratio for experiencing symptoms of motion sickness in a VR environment are actually even higher, with one finding that for every one man who gets sick, four women would—that's big numbers. No one knows exactly why this is, but it's believed to be connected to the hormonal cycle—and apparently women are more likely to feel motion sickness when they're menstruating.
Golding tells me that age plays a huge factor too, with signs of motion sickness usually beginning at age six to seven and peaking at nine. It can then decline throughout puberty and peak again at around 20 years old - but everyone is different, these are just trends. As well as age and gender, you can thank your parents as it's often genetic too. And as you'd probably expect, those with migraines, inner ear conditions and problems with their sight are likely to be more susceptible.
How can VR companies stop us all from throwing up?
Although many of us are willing to feel sick while we travel, VR in a mainstream setting is mostly about entertainment. It's vital companies find ways to combat motion sickness—or at least make the experience as comfortable as possible—if they're going to appeal to a wide audience.
Golding said a lot of the issues can be addressed, mainly that's with less lag between load time: "Companies need to understand how important it is and value the computational speed. Some headsets are focused on more power for a better picture, but should be increasing the speed at which the screen refreshes instead."
But as we learned above, it isn't just about lag time. Headsets that are placed further away from our faces or don't require our eyes to strain as much probably need to be explored. How that'll actually work remains to be seen given the compact design and ease of a small headset are appealing to many customers
Many of the big brands are addressing these issues. The Oculus Rift, HTC Vive and PlayStation VR all have high frame rates, which dramatically reduce lag. But with instances of motion sickness still being reported, there's a chance it's still not fast enough—at least for certain people.
Golding suggests building systems with only partial VR - or mixed reality -would massively help, so you can still see the real world in some way behind it, but that'd obviously take away from the immersive experience we're all paying for. The Vive's Chaperone feature is one example of bringing the real world into the virtual.
He also said tech companies need to be wary when they're imposing VR onto other situations. So getting someone to sit in a fairground ride as they wear VR, military training using VR, or driverless cars, because it might open the door for even more sensory conflicts. A sensory conflict on top of a sensory conflict? I feel nauseous just reading about it.
Yet another possible solution which Golding didn't bring up but that's on the horizon is the eye tracking from headsets like FOVE - not a feature on the current gen of headgear. We asked a few of the major tech companies in the VR space what they were up to. Samsung, which makes the excellent mobile Gear VR headset, didn't want to comment. A Sony rep told us: "We continue to watch reactions and share key learnings with developers so that software will continue to be made with the comfort and safety of the player in mind."
Which doesn't feel particularly promising, but does suggest they're aware of the issues. HTC spoke to us about the HTC Vive and provided the best comment. "We highly encourage developers to do a lot of testing when it comes to locomotion mechanics and anything which can cause visual and inner ear senses to feel out of sync," said VR product specialist Shen Ye. "Additionally we ask they target running at the 90 frames per second the Vive headset runs at, which reduces juddering and latency problems.
"Nausea and/or motion sickness in VR is caused by high latency and low refresh rates. Vive solves for this better than any other VR solution on the market. Our content runs at a minimum of 90 fps and we have extremely low latency. This combined with SteamVR tracking accurately positions both you and your controller in your virtual space within 1/10th of a degree of accuracy."
Consider it while you create
As we've learned from Golding, this isn't about solving one issue and everything else falling into place. Which means VR content might be just as important as hardware.
I spoke with Alina Mikhaleva, managing partner of Spherica, a company that has created a stabilisation technology that allows creators to make smooth camera movements. "When filming in VR, we need to think about the VR camera as a viewer's head. Any uncontrolled horizon shaking, spinning, or active action will cause an unbearable motion sickness effect."
"At the same time, none of the VR camera manufacturers (from consumer-oriented Samsung 360 to professional GoPro Omni, Nokia OZO, Jaunt or Google Odyssey) offer any solution for camera stabilisation, leaving content creators with a very limited choice of either filming boring static content that lacks storytelling and engagement or moving the camera without hardware stabilisation, triggering motion-sickness."
"Our gimbal does what a traditional film camera gimbal does – it keeps the system in constant balance no matter how you move the camera. However, since any 360 camera setup is made in a circular arrangement where cameras are facing in all possible directions, we had to basically rethink the whole concept of a classical gimbal, since we now need to keep it inside the spherical array arrangement of the cameras."
Start with short sessions of very comfortable experiences and ramp up
Jamie Mossahebi, VR video lead at Happy Finish, suggests there are steps you can take to ensure the content you're creating is right for VR: "Test camera moves rigorously, keep them smooth and clean," he suggested. "When in doubt test the shot and find someone who is particularly sensitive to motion sickness to try it. Throwing a 360 camera on an extreme sports athlete's helmet is the laziest creative going so think outside the box."
"Be mindful of your compression settings depending on what headset you are targeting, some may struggle to play back heavy videos which causes lag - another major cause of VR sickness."
Of course, there are also ways we can minimise the effects ourselves. For some of us motion sickness feels really strong, but it could be a case of getting used to it. Pieter Rossouw, founder of Totem Labs VR, told me: "Gradually exposing yourself to VR experiences seems to allow the brain to learn that it's OK. Best to start with short sessions of very comfortable experiences and slowly ramp up to longer and more intense experiences over the course of weeks or months. If at any point you begin to feel uncomfortable or sick, it's best to stop immediately."
There are a few tech solutions that have been developed in recent months too, like a Virtual Reality nose that could give people a point of reference. You could also try anti-motion sickness medication and a bunch of home remedies your gran probably knows really well—people are always telling me to take ginger. However, prepping yourself for a VR experience beforehand hardly feels like the future, especially when experts like Golding suggest there are some ways we could be thinking outside-of-the-box (or headset) to minimise the symptoms.
Creating hardware for everyone
The reasons for addressing motion sickness here shouldn't just be focused on selling as many headsets as possible and making sure Sony's customer service line isn't ringing off the hook with all those PlayStation VRs it's shifting. There are some very serious issues that need to be discussed around discriminating against people as VR becomes more widespread—particularly women.
As women are around four times more likely to experience motion sickness symptoms than men in a VR environment, it means not only might they be unable to use VR for entertainment purposes, but for other purposes too.
For example, VR is used in the military for training purposes. Does this mean women aren't going to get the training they need when men would? Will teen and young university students struggle with VR assignments because they're girls?
There's talk at the moment about how things like VR porn aren't tailored to a female audience in terms of content. But the hardware clearly needs to be built so everyone can use it, including women, first otherwise it won't matter what they're seeing. Without a more mindful approach to the female experience at every stage of the process, tech companies risk alienating them. Of course motion sickness does still affect men, but it's important these issues are addressed so the benefits of VR aren't skewed towards men, whether it's at home, at work or anywhere else.
Although motion sickness is the bane of some people's existence (*puts arm in air defiantly*), it's usually shrugged off by many—or masked by medication—because it's experienced during travel. And as unpleasant as that can be, many see it as an unnecessary evil to get from A to B. But we put on VR headsets for to be entertained, to be impressed and for an escape. It's meant to be fun. That means it's much harder to shrug off a feeling of nausea when you're inflicting it on yourself.
So with the fun factor, the potential for upgraded headsets and the fact it's possible to make the experience more enjoyable, we're looking forward to seeing what the big VR companies improve to stop people from feeling sick with their headsets on.
And let's remember this isn't a case of selling as many headsets as possible (though there will surely be a correlation). With VR set to become a huge part of all aspects of our lives, more needs to be done to make this groundbreaking, finally realised technology - which at its core allows anyone to experience anything regardless of background - accessible and comfortable for everyone.
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