Monday, February 13, 2012

Virtual reality and phobias

For Veronica Jones, the last straw was canceling her anniversary trip to Cancun. A 32-year-old attorney, Jones (a pseudonym) had always been a fearful flyer, but she'd managed to travel the world anyway: Doping herself up on Benadryl, she says, helped lessen her panic.
But over the years her fears worsened, and eventually over-the-counter remedies were no longer enough to overcome them. On a two-leg trip from her home near Washington, D.C., to Argentina to visit her in-laws, she'd nearly insisted her husband leave her at the airport in Miami. In the end she got on the plane, but the experience was so traumatic she vowed not to fly again.
So when her husband surprised her with tickets to Cancun--and a reservation at the Ritz-Carlton--she reluctantly asked him to cancel the trip.
"That's when I knew I needed to deal with this," she says. "When it started to affect not just me, but also my marriage."
For help, she turned to Curt Buermeyer, PhD, a psychologist who helps clients overcome phobias and other anxiety disorders. Buermeyer and his colleague Keith Saylor, PhD, use traditional cognitive-behavioral therapy methods, but with a high-tech twist. Their practice in the suburbs of Washington, D.C., is one of about 30 around the country that use virtual reality--3-D computer graphics that simulate environments in the real world--to help clients confront their fears.
For Jones, that meant she could take "virtual" flights--via a video screen in a helmet and a vibrating chair--in the safety of Buermeyer's office before stepping foot on a real plane.
"The important thing to realize is that virtual reality is a tool in cognitive-behavioral therapy," Saylor says. "It's not the answer in and of itself."
It is, though, proving to be a useful tool--dozens of studies over the past decade have shown that virtual reality can help people overcome fear of spiders, heights, storms, flying and even public speaking.
And recently, researchers have been investigating ways to make virtual reality even more "real" and the therapy even more effective.
Virtual history
Clinicians have used cognitive-behavioral therapy to treat phobias since the 1950s. In this type of therapy, patients learn to identify the thoughts that are causing the feelings or behaviors they want to overcome, and then learn how to replace those thoughts with more helpful ones.
Exposure--introducing clients to controlled amounts of the thing they fear--is a key component of most cognitive-behavioral therapy. For years, therapists had two types of exposure to choose from: real, in vivo exposure or guided imagery in which the patient imagined his or her fear.
In the early 1990s, a few psychologists began to imagine a middle ground--using the newly available virtual reality technology to give patients an experience that was more realistic than imagery, but more convenient than in vivo exposure.
In 1995, psychologist Barbara Rothbaum, PhD, of Emory University, and computer scientist Larry Hodges, PhD, now at the University of North Carolina at Charlotte, published the first study examining the effectiveness of virtual reality therapy. In a paper in the American Journal of Psychiatry (Vol. 152, No. 4, pages 626-628), they found that virtual reality helped patients overcome acrophobia, or the fear of heights.
The next year, psychologists Albert Carlin, PhD, and Hunter Hoffman, PhD, of the human interface technology laboratory at the University of Washington, published a study in the journal Behavior Research and Therapy (Vol. 35, No. 2, pages 153-158) that demonstrated that virtual reality could help patients with a debilitating fear of spiders--including a woman they nicknamed "Ms. Muffet," who was so afraid of spiders that she duct-taped closed the doors and windows of her bedroom each night.
In 1996, Rothbaum and her colleagues set up a company called Virtually Better to commercially develop and distribute their virtual reality software and equipment to clinicians. A Spanish company, Previsl, sells a similar system in Europe. The two companies provide virtual environments including an airplane, elevator and thunderstorm to nearly 60 psychologists and other therapists in 13 countries, says Virtually Better CEO Ken Graap.
Why virtual reality?
Two of Virtually Better's clients are Saylor and Buermeyer. At first glance, the set-up in Saylor's office is unprepossessing. A regular office chair sits on a small, gray-carpeted platform a few inches high. The headgear--sort of like an oversized bicycle helmet with earphones and a flip-down screen--is attached to Saylor's desktop computer.
Inside the contraption, the view is more impressive. In the airplane scenario, for example, clients see an image of the inside of an airplane on the screen. Sensors in the helmet pick up any head movement, so when the user turns his head he can look anywhere from out the window to across the aisle. Over the earphones he hears the sound of flight attendants and the pilot making announcements, and the platform rumbles and shakes to simulate the feel of engines, turbulence or descending landing gear.
Overall the experience is convincing but still cartoon-like; there's no mistaking this for a real flight. But, Saylor says, for most people with phobias that doesn't matter--it's real enough to elicit their fears.
And the advantages of virtual reality, Saylor explains, are numerous. First, he can carefully control the amount of exposure in each session. For fear of flying, for example, he can slowly take clients through the steps of a flight--from takeoff to landing--over many sessions, waiting at each step and working with them until they feel comfortable and habituated.
"For some people, we might not even get off the runway for several sessions," he says.
Also, he explains, there is the convenience and confidentiality factor: "I could take someone with a fear of elevators onto a real elevator, but this way they don't have to worry about running into people and explaining who this guy with them is." And, of course, it would be impossible to arrange a trip on a real airplane for each therapy session.
Finally, says Hoffman, it's easier to get people with phobias to agree to exposure therapy when it's begun virtually, rather than in vivo. "In vivo [exposure therapy] is very effective, but you have to convince people to try it," he says. "By definition, someone with a phobia wants to avoid what they're afraid of."
Of course, virtual reality has some disadvantages as well. First, there is the cost: A Virtually Better system sells for more than $6,000 and requires a monthly licensing fee. That price tag doesn't put it out of reach for most therapists, says Saylor, but it is a significant investment.
Also, the therapy does not work for everyone--and it works better for some people than for others. Some studies have found, for example, that people who are more hypnotizable or more easily able to block out distraction and be absorbed in an activity like reading are also more likely to benefit from virtual reality exposure therapy.
"There are people who try it and it just doesn't work," says Saylor. "They say, 'I'm not really on a plane.' But that's not true for most people."
The goal, of course, is to eventually move all clients from the virtual to the real world--Saylor and Buermeyer expect their flight-phobic clients to book at least one airplane trip by halfway through their course of treatment.
Veronica Jones has done better than that. She's experienced 34 real takeoffs and landings since beginning her work with Buermeyer--and this year, she'll be flying to Montreal to celebrate her anniversary.
New research directions
One of the keys to effective virtual reality treatment is "presence," or making the user feel completely immersed in the virtual world, says Brenda Wiederhold, PhD, a psychologist and the executive director of the Virtual Reality Medical Center in California.
"We're always looking at how we can improve presence," she explains. The improvements don't have to be high-tech: "Some studies have shown that thousands of dollars worth of better graphics don't help, but things like a $10 fan blowing on your face do."
For example, Hoffman and his colleagues have recently begun to experiment with having patients touch a fake furry tarantula while visually immersed in the virtual "Spider World." In a 2003 study in the International Journal of Human-Computer Interaction (Vol. 16, No. 2, pages 283-300), they reported that this combination of tactile and visual experience was twice as effective as therapy with visual stimulation alone.
Barbara Rothbaum's research has gone in a different direction. She's begun working with neuroscientist Michael Davis, PhD, to investigate whether administering the drug D-Cycloserine (DCS) before virtual reality treatment can enhance treatment effectiveness. Research has shown that DCS--which is now used mainly to treat tuberculosis--binds to neurotransmitter receptors in the amygdala, the seat of fear in the brain, and can extinguish fear in rats. In a study published last year in the Archives of General Psychiatry (Vol. 61, No. 11, pages 1,136-1,144), Rothbaum, Davis and their colleagues found that giving people a dose of DCS before two sessions of virtual reality therapy increased the effectiveness of that therapy.
"The great thing is that this is a drug that's already been approved for other uses, and it has pretty much zero side effects," says Rothbaum.
Overall, virtual reality treatment--with or without pharmaceutical intervention--provides a new hope for patients like Jones, whose fears interfere with daily life.
"This whole experience has been one of the best investments--of time and money--I've ever made," she says.

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