When you think about it, virtual reality is such a step change in immersion, mediums like TV and video games seem abstract by comparison. What we're not asking enough, is what impact this might have in the long run.
This is virtual reality's second coming; we've been tinkering with the idea since Morton Heilig built the Sensorama in the 1960s, but it wasn't until the 90s that VR got its first "boom". Sadly Hollywood's promises of breathtaking alternate universes were beyond what the technology of the era could reach, dooming it to failure. But even back then, people had concerns about what long-term exposure to VR could do to the human mind. A study carried out at Michigan State University concluded that VR rewired the brain, but was unable to determine if longer term effects were possible.
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Now we're in 2017, VR is back (again), and still we've done little to interrogate whether our brains are even ready for this next level of human-machine interfacing. But it's coming: various researchers have revealed to Wareable that work is underway to look further into the impact virtual reality could have on our brains and eyes.
The smoking gun
The Michigan State study from 1999 revealed evidence of temporary changes to the brain from long-term VR exposure, but it left a question dangling over whether more permanent changes could come about - and if they could be harmful, or even positive.
A study by neuroscientists at the UCLA published in 2014 showed a concerning reaction from the brain to virtual reality. Researchers built an immersive VR simulation in which rats were placed in harnesses and sat on top of a ball in an cinema-like room - as they moved, the scenes around them did too, creating the illusion that they were navigating through this virtual world. "It was like a fully surrounding IMAX," Mayank Mehta, the study's senior author, tells us. "Including under the feet, which is why it was very compelling."
The rats were fooled, even trying to touch objects in the virtual world and, perhaps most interestingly of all, taking naps only where the scientists "placed" rewards of sugar water - even though these spots were no more comfortable than any other part of the virtual world. The researchers found was that while the rats were in the virtual world, neurons in the hippocampus - the region of the brain associated with forming memories and maps, and which has been linked to conditions including Alzheimer's, strokes and schizophrenia - behaved extraordinarily differently. "When we looked at the neurons in this part of the brain, 60% of neurons shut down in virtual reality - which is a big deal," Mehta tells us. Not only that, but the maps created in the remaining 40% were corrupted.
"We didn't expect this, nobody expected this. A couple of scientists had looked at VR before us and concluded everything is fine. We are the only lab which has done this head-to-head comparison - same rate, same neurons, same visual scene."
We need to see what happens when people use VR not just for half an hour but for hours on end for years
So why did it happen? Their best guess is that because while the virtual alternate reality was compelling, a lack of proximal cues - like smell and touch - created a disassociation in the brain. These cues would usually help the brain form a "map", but in virtual reality they're missing, which causes this neural network to go haywire. Furthermore, says Mehta, "What we found is that the activity pattern you see in VR in normal rats resembles the activity pattern people have seen in mice with Alzheimer's in the real world. Which begs the next obvious question: what could it mean for longer-term exposure in humans?
"That's the key question and that's something that needs to be researched," says Mehta, who tells us his team is currently at work on a new project to build on these earlier findings, to be published in the coming months. "This needs to be investigated carefully. We need to see what happens when people use VR not just for half an hour but for hours on end for years."
The thing is, very few people are using VR for hours on end. Compelling games are still thin on the ground, while other side effects like motion sickness and dizziness prevent many people from immersing themselves for long periods of time. Plus, as Skip Rizzo, director of the Medical Virtual Reality Institute for Creative Technologies at USC, flags, getting a large population study of users immersing themselves for eight hours a day would be unethical.
VR being used to treat post-traumatic stress disorder
But Rizzo believes research needs to be done, and that the time is now. "We're in a renaissance of VR but there's a lot of money being wasted, being thrown at things that are redundant or ill-conceived" he says. "If some of that money was earmarked into a pot to study these kinds of things, then maybe we would not only know what we were facing for the long run, but also find ways to reduce any negative impact so that some of these companies don't have the inevitable lawsuit. I'm sure that, whether the damage exists or not, someone's going to claim it."
You're embodying someone in novel environments and that typically has a positive impact on the brain
Rizzo isn't immediately worried about catastrophic, psychophysiological effects of VR, and is more excited by the positive impact virtual reality is already showing - including in the treatment of post-traumatic stress disorder and brain injuries. In fact, he predicts we'll find brain enhancements with prolonged usage, though he still calls on deeper research to be done. He admits he has some concerns that hours on end spent in virtual simulations could have other effects, like altering our hierarchy of responses to real-world situations.
"I think VR is going to have an effect because you're embodying someone in novel environments and asking them to participate in some activity. That usually has some impact on the brain, typically in a positive way. But will it mean people learn things in VR that don't transfer in a positive way to reality when they're outside of it?"
For example, he proposes, if a kid is in a virtual kung fu dojo for several hours a day and then finds themselves in an altercation with another person in the real world, would their response be any different? "Is your first strategy going to be to kick him in the head? Or are you going to try to negotiate?"
A sight for sore eyes
The relationship between VR and the brain holds many questions, but the impact on our eyes also needs to be looked at more carefully. Martin Banks, professor of optometry and vision science at the University of California, Berkeley, says that, again, we just don't know what impact VR could have in the long term, and that there's only one red flag he sees for now.
"There is increasing evidence that doing what we call near-work - reading, looking at your cell phone, playing video games on your cell phones - causes children to become near-sighted, and that is a healthy concern because when you become older, it puts you at greater risk for some retinal diseases."
Before you throw off that headset, it's important to know the difference between optical and physical distance. While the display sits just inches from the eye, it's where the eye focuses that's important. In most headsets that's over an arm's length away, which is better than looking at a smartphone up close for extended periods - and which is probably why the participants in a recent Beijing Institute of Technology study showed less impact from VR than tablets. It concluded that VR can improve the eyesight of pre-teen users.
So while we often query whether children, whose sight and mind are still developing, could be more exposed to dramatic effects, Banks wonders if the opposite case could be true: "Kids are usually more adaptable, so I can make the opposite argument that we should be less concerned about kids. That they are more able to adapt anything you give them."
Right now our eyes can't adjust their focus naturally on objects at different distances as they do in the real world, something that's called the vergence-accommodation conflict. This leads some people to feel sick, while also breaking the illusion of virtual reality. Oculus told us that it is working to solve this conflict using a trick to "bend" light as it hits the eye, and this should make for more comfortable VR experiences with less eye fatigue. All the while though, that focal distance must remain far enough away to not cause any damage.
Stay safe with VR
Banks is now planning a new set of research with Jenny Read, professor of vision science at Newcastle University, to build on her 2014 study into the effects 3D TV had on viewers. "We plan on having 600 people, and for one year, so that's the kind of thing you need to do to feel confident. They're going to be given video games and entertaining stuff."
Banks says he wants to do this long-term, large population study so they can "look for any issues people should be worried about".
Which is where we stand with all of this - we just don't know enough yet. In these nascent days of virtual reality, it can be easy to dismiss any potential long-term effects when only a small subset of people are using the technology extensively. But as it gets more immersive and more compelling, the more time we can expect be spending in these virtual worlds - which is why it's crucial we start digging deeper into the consequences - good and bad - that VR may bring.