More than 90 per cent of the acrophobics taking part in a study in California were reported to have reached self-assigned 'height goals'.
The technique, christened virtual therapy, opens up a new market for virtual reality systems in medicine, where at present they are used in training, allowing doctors to see inside 'virtual' patients.
The virtual environment in which the subjects were immersed showed a cafe with an elevated patio and a plank from the patio to a bridge. The panorama was created on a virtual reality system from the British company Division. Thirty-two volunteers donned the helmet display system, which tracks head movements and instantly displays the scene corresponding to each new head position. The sufferers had to leave the cafe and walk on to the patio, crossing the plank and exploring the bridge. The system allows them to operate much as in real life, looking over the edge of the plank or the bridge, for example.
Heart rate and blood pressure showed the acrophobics were experiencing the stress and acute anxiety associated with actual encounters with heights.
After the virtual encounter, the volunteers were given challenges in the real world, such as driving across a bridge or going up in a glass-sided lift while looking out at the surroundings. More than 90 per cent managed to complete these tasks. Ralph Lamson, from the department of psychiatry at the Kaiser-Permanente Medical Group in California, who carried out the study, believes virtual reality could be used to treat other phobias.
'Virtual therapy gives the individual an opportunity to approach the thing they are fearful of in a virtual environment. Being immersed in a virtual feared situation is very close to the real situation. After virtual therapy, participants feel they have already had a success. This appears to be a strong confidence builder,' he said.
A couple of years ago, researchers at Leeds University announced they had successfully treated arachnophobia, or fear of spiders, by exposing sufferers to 'virtual' spiders.
In another form of virtual therapy, a group at the University of Washington, Seattle, has succeeded in helping people with Parkinson's Disease, who often experience difficulty in initiating and sustaining walking. The researchers simulated an effect called kinesia paradoxa, in which normal walking is triggered by putting obstacles at the feet of Parkinson's patients. Although this effect is well known, it has not been a practical way of treating people. Virtual reality was used to simulate the physical obstacles without the problem of placing them in front of patients and risking tripping them up.