Could the Surgeon General Warn: 'VR Is Hazardous to Your Health'?
Virtual reality causes nausea, bad judgment and anti-social behavior, say experts who have tracked the effects of simulators
Grasping reality through illusion -- absent its dangers, disease and costs -- has become the rallying call in the much-hyped field of virtual reality.
But VR, as it is known to the digerati, is beginning to look like it could be as dangerous as immersion in the real thing -- at least, so says NASA and the Department of Defense's chief adviser on the effects high-tech simulators have on the human body.
Nationwide, the list of reported maladies from prolonged immersion in computer-generated worlds continues to grow: vertigo, motion sickness, flashbacks, spontaneous seizures, excessively nerdy and antisocial behavior, even biological infections -- not to mention head lice -- from strapping on much-used equipment.
"Product liability is going to make [manufacturers] get smart very quickly," said Robert Kennedy, who for 15 years studied simulator sickness for two of its first, biggest users, the military and the space program.
From that experience, he notes that the ability to sue the government for simulator and virtual reality related injuries is limited -- in fact, he's not aware of a single instance of a successful suit in the military. But with its high-tech machinery and mission of patriotism, the rules are different than if Junior runs a car up a tree after a few hours at the arcade's virtual race track. In short, manufacturers won't be so lucky, says Kennedy.
As sophisticated simulation and virtual reality technology pioneered in the military becomes commonplace in video arcades, amusement parks, schools and businesses, will awareness of the potential dangers follow? Will restrictions be imposed, warning labels affixed and lawsuits filed?
So far, manufacturers of virtual reality equipment appear to have paid little attention to the problem. Those contacted for comment in this article did not return phone calls.
Says R. Bowen Loftin, a physics professor at the University of Houston and creator of many of the government's more sophisticated virtual reality environments: "I'm very concerned about people in casual uses."
For instance, controversial claims about cellular phones causing cancer provoked major headaches for cellular companies, even with scant scientific evidence.
At the moment, the VR field is operating with similar scientific uncertainty -- great for product-liability lawyers, and potentially worrisome for the public.
The potential dangers of VR go beyond the problem of nausea or disorientation. People prone to epileptic seizures -- approximately 1 percent of the population -- are subject to a condition called "flicker vertigo," which usually occurs when computer screens are not regenerated at least 15 times per second. With today's displays, that's generally not a problem.
But that figure applies mostly to smaller screens. As the field of vision expands, and brightness and clarity increases, the screen must regenerate itself more frequently to prevent the eye from detecting flicker.
That flicker, in turn, can conflict with the electrical frequency-output of the brain -- and in the case of those prone to epileptic seizures provoke an attack. For larger displays, where the head moves relative to the screen, only a frequency of 500 times per second would eliminate all flicker.
Other potential (and mostly unproven) potential problems include radiation emissions from head-display mounted devices in close contact with the eye. Virtual reality, in less prosaic terms, results from encoding a digital version of reality in a computer -- a kind of downloading of reality into silicon -- and allowing humans to interact with it.
That includes everything from more traditional forms of virtual reality, such as cockpit simulations for pilots in training, to donning data gloves and visors for a battle with a digitized warrior in a video arcade.
The main downside to virtual reality is this: the body tries to coordinate visual and inertial inputs. Combining signals from the eyes and various other body endorgans -- specialized structures at the end of nerve fibers having a sensory function -- allows an individual to maintain a sense of equilibrium. Throw the two out of sync -- or any set of sensory inputs, for that matter -- and the body begins to display characteristic symptoms.
For example, the appearance of movement -- seeing a road coming at you 100 miles per hour -- should be accompanied by the forces of inertia that act on a body moving at such a speed. Naturally, virtual reality can't transport a body at 100 miles per hour; it can only maintain the illusion of doing so.
Herein lies the source of VR-sickness, and experts say the problem may ultimately be unsolvable -- just as there is often no cure for chronic sufferers of seasickness. It's a take-at-your-own-risk kind of venture, like the high-powered VR-style rides at some of the nation's premier amusement parks.
The body does have the ability to adjust. Theoretically, it is possible to stimulate endorgans -- blowing a puff of air into the inner ear, for instance -- to provide sensory inputs needed to match a visual illusion of motion.
Studies at the Defense Department have shown that prolonged exposure to poorly designed simulators causes 50 to 70 percent of users to suffer some form of simulator or VR-sickness.
And even the best simulators prompt symptoms in 30 percent of users. A recent study Loftin did for NASA found that out of 105 prolonged virtual reality-users, 35 percent suffered from eye-strain or headaches, 20 percent from nausea and 12 percent from disorientation.
Pilots, following a session of two hours or more in a flight simulator, have reported flashbacks hours later -- in some cases nearly causing fatal car accidents. Those flashbacks occur in about 1 percent of all cases. That's why pilots aren't allowed to fly a real airplane for at least 48 hours after a session in the simulator.
"We have gone too fast technologically," says Kennedy, a vice president at Essex Corp. of Columbia, Md. "My caution would be to explore better the psycho-physical implications of these devices before we field them."
Kennedy, who has a doctorate in experimental psychology, began studying motion sickness while in the Navy, where he also got involved in early space-sickness work. For the last 15 years he has studied the impact of prolonged immersion by pilots -- for a half hour or more -- in simulators. Now he has turned his attention to virtual reality.
His studies have shown convincingly that "when you fool a sensory system, you run a risk." One famous study put glasses on an individual that turned his entire field of vision upside down. He was completely disoriented at first and unable to function. But within hours, he made a complete adjustment and was able to function normally. But he faced the same unpleasant readjustment when the time came to remove the glasses.
Thus disorientation necessarily accompanies an individual adapting from one reality to another, says Loftin.
Each individual's field of vision and point of focus is different -- and sensitive to changes within a millimeter. That focus, which results in an integrated image, is affected by the lighting and perspective of the outside world. Enter a virtual world, where lighting and perspective are often dramatically different, and an individual must readjust to maintain focus.
Other liabilities include head and neck injuries from prolonged use of poorly designed equipment, repetitive stress syndrome, "game-player thumb" from video games, even outright addiction and assorted other mental pathologies.
Chris Dede, a professor at George Mason University who studies the sociological impact of advanced computing technologies, put the challenge this way in an unpublished article: "Alfred Lord Tennyson's poem, 'The Lady of Shalott,' depicts the complexities of understanding the real world via vicariously experiencing its mirrored, magical reflections in a synthetic environment. His poem ends tragically; ultimately, its protagonist is unable to live either in the virtual or the real world."
Still, the dangers of virtual reality can be exaggerated, and have been in science fiction. People have been riding roller coasters for years. Reports that skin lice and other skin diseases have been transferred from user to user after using the same helmet-mounted display or data glove are anecdotal -- and are no different from hygenic risks people face in public restrooms.
Moreover, Kennedy points out that most virtual reality rides today, in addition to being expensive and often crude, rarely last more than a minute. VR sickness usually occurs after exposure of 30 minutes or more to extremely sophisticated, multi-million dollar virtual worlds.
Kennedy is finishing up what he calls a test of "posture disequilibrium" which measures head position before and after a virtual experience. He is adapting a version that would numerically equate a person's fitness to function in reality to alcohol breathalyzer tests.
And some manufacturers of VR equipment have seen the writing on the screen. Nintendo, for instance, puts a disclaimer on video-game packages warning people subject to epileptic seizures that they could be in danger when using the game.