Researchers in Medicine and Psychology Explore Uses of Virtual Reality
By FLORENCE OLSEN
Virtual reality, still viewed by many as an expensive high-tech toy, is gaining new respect from cognitive psychologists, clinicians, and therapists who say their experiments with the technology have produced surprising results. The technology is now moving out of computer-science research labs and into hospitals, where it is being used to treat pain in burn patients and to help veterans overcome chronic post-traumatic stress disorder.
Virtual reality creates three-dimensional virtual worlds through a combination of computer graphics, body-tracking devices, and head-mounted displays. Some academic researchers say they have found it to be effective for assessing cognitive abilities and, in some cases, for rehabilitating people with cognitive impairments.
Virtual reality gives the cognitive researcher flexibility and control in creating useful test scenarios, says Benjamin Watson, a visiting assistant professor of computer science at Northwestern University. "In the real world, you can't just make a building go away," he says. "In V.R., you can." He also says that virtual reality eliminates a degree of bias, or lack of uniformity, that is often difficult to control using traditional cognitive-assessment tools.
For all of its advances in the last five years, virtual reality "still isn't photorealistic, but it's good enough," Mr. Watson says. For example, he says, it can be useful for assessing impaired cognitive functions in patients with brain injuries or Alzheimer's disease.
Researchers at the University of Washington describe promising results they have obtained from using virtual reality to supplement narcotic drugs for burn patients who experience excruciating pain while receiving daily wound care. Distraction has long been known to be effective in reducing acute pain, says Hunter G. Hoffman, a research engineer in the university's Human Interface Technology Laboratory. "We've explored the use of immersive virtual reality for taking distraction to a new level," he says.
He says the idea for the experiments with burn patients came from watching kids experience virtual reality and seeing "how oblivious they were to the real world." Starting from a virtual-reality environment created for training fighter pilots, Mr. Hoffman added "a bunch of snow features" -- snowflakes falling, an icy river, a waterfall -- to create a "virtual-reality analgesic" that he calls Snow World. "The idea is to trick the patients into thinking they're in a cold place so that they reinterpret their pain," he explains.
To avoid a problem that V.R. researchers call "simulation sickness," Mr. Hoffman screened patients to eliminate those who were susceptible to nausea or motion sickness. He also took care to design Snow World to minimize nausea. Burn patients, he says, tend to have more problems with nausea than the average person does because so many of them are being given morphine, which causes nausea.
Mr. Hoffman says he has been surprised by the promising results he has observed in measuring patients' pain levels while they are in and out of virtual reality. He had not anticipated, for example, how highly motivated burn patients would be to enter virtual reality.
Following their initial successes, the Washington researchers say they are now looking for ways to maximize the effectiveness of virtual reality and expand its use in treating burn patients.
Mr. Hoffman notes that patients suffering from chronic -- rather than acute -- pain are probably not good candidates for virtual-reality therapy. "The other kind of pain is going to be more tricky to treat using virtual reality," he says.
In studies led by Larry F. Hodges, an associate professor in the Georgia Institute of Technology's College of Computing, researchers found that Vietnam-war veterans suffering from chronic post-traumatic stress disorder, or P.T.S.D., improved after a series of therapy sessions in virtual reality.
The idea, Mr. Hodges says, is to expose the patient gradually to the situation he or she fears most, until finally the person can be in that situation without experiencing overwhelming anxiety. "If your fear is driving, you might start by sitting in the car with the motor off," he says.
In working with veterans, the therapist tries to get the patient to tell his story -- and to retell it over and over again. "The idea is to reprocess his memory of this event," Mr. Hodges says.
Not all veterans find it easy to talk about what happened to them, however. In virtual-reality environments, some veterans who have been unable to talk at all about their war experience have become verbal and animated.
In a dramatic demonstration, Mr. Hodges plays a videotape in which a former tank commander -- his identity masked by a V.R. head-mount display, and his therapist seated nearby -- is pacing and pivoting, alternately talking to and shouting at his tank crew in a virtual reality crackling with mortar fire. The veteran had been the sole survivor when his tank crew was attacked by North Vietnamese soldiers.
After six months of virtual-reality therapy, eight veterans had improved enough that their conditions were upgraded from severe to moderate, Mr. Hodges says.
Because of the successes reported by academic researchers, two veterans hospitals -- one in Atlanta, the other in Boston -- have purchased V.R. systems to treat veterans with anxiety disorders. Mr. Hodges and his research partner have also formed a company, Virtually Better Inc., to create V.R. systems for clinics.
Because it is expensive to create virtual-reality environments, the Georgia Tech researchers have focused their efforts on creating V.R. experiences to support therapy for large patient populations, such as Vietnam veterans. More than 800,000 former combat soldiers, most of them veterans of Vietnam, suffer from chronic anxiety disorders. They make an ideal group to target in creating a virtual world, Mr. Hodges says, because nearly every veteran experienced what the V.R. simulates -- arriving or departing in a Huey helicopter in an open field surrounded by jungle.
"As the software tools get better and we can develop these things faster, we hope we can do more environments," he says.
Albert "Skip" Rizzo III, a research assistant professor at the University of Southern California's Integrated Media Systems Center, says he is using virtual-reality classrooms to evaluate children suspected of having attention-deficit hyperactive disorder. Because the diagnosis is such a controversial one, Mr. Rizzo says, it is important to find an accurate assessment tool for making the diagnosis.
Measuring a person's attentiveness in virtual-reality environments is a starting point for what Mr. Rizzo says he hopes will be extensive applications for virtual reality in measuring cognitive impairments.
Background articles from The Chronicle: