At 38, Emma was a walking Which? guide to therapies: behaviourist, cognitive, hypnosis, family and psychiatry. For 18 years she had tried the lot in an increasingly despairing attempt to conquer her agoraphobia. So it was with considerable scepticism that she embarked last year on a new therapy - Eye Movement Desensitisation and Reprocessing (EMDR) - that was apparently achieving miracle cures across the United States. What made her even more wary was that it sounded as absurdly simple as it was bizarre.

The therapist sits in front of the patient, holds up a finger and flicks it back and forth in front the the patient's eyes. The patient's eyes must follow these movements and at the same time they must imagine whatever it is that has caused the feelings of panic or terror. And that's it. Sometimes within a few sessions, usually within a few months, the fears become manageable. In her first session Emma concentrated on her fear of flying. 'As I watched her hand move and thought about being trapped on the plane, I began to feel worse and worse, just on the edge of a major panic attack. But then, curiously, just as the panic peaked, it began to subside,' she says. Over three months other emotionally charged images, to do with her mother's anger and her own fear of sadness, surfaced but they all became bearable under the influence of the moving finger. Now she believes she will be able to lead a normal life and is planning a plane trip.

Emma is one of many converts to EMDR. It was first discovered in 1987 by a psychology student, Francine Shapiro, while she was walking in a park in California.

A diagnosis of cancer had sent her on an alternative therapy pilgrimage. While studying for her PhD at the age of 39, she noticed that her own disturbing memories seemed to dissolve when she spontaneously moved her eyes from side to side. She began experimenting with colleagues and ran a study a group of people who had, on average, been in therapy for six years and had suffered from flashbacks and nightmares for 23 years. After a single session all reported significant improvement.

Relentlessly she began to push her technique at seminars, conferences and in the press. Her big break came in 1988 when Dr Joseph Wolpe, one of America's most respected psychologists, endorsed it. 'There are certain cases in which this is the only known potent method,' he says. He developed the technique for dealing with phobias by bringing people gradually closer to the thing they fear.

To date, there are 4,000 practitioners in the US, Israel and Australia using EMDR and recently a few have tried it in the UK. Later this year, the first training session in EMDR techniques will be held in London.

One of the organisers of the London conference is John Spector, clinical psychologist at Watford General Hospital. 'I was sceptical when I heard about EMDR, but I tried it on one woman who was in shock after being raped and got impressive results. It is very good for uncovering the deeper fears that traumas often awaken.' In the United States, EMDR has had its most dramatic successes with people who are suffering from the after-

effect of traumatic experiences such as car crashes, rape or war. 'This technique has transformed the way we handle Vietnam vets,' says Steve Silver, a psychologist from the VA Centre in Coatesville, Pennsylvania. 'Helping these people to adjust is still a big problem. More Vietnam vets have committed suicide now than were killed in the war. About four years ago the best we could do was to have the clients talk. Today EMDR is the most effective thing we do. Some people get complete resolution of their difficulty with a particular memory in one session.'

Another supporter is the psychiatrist David McCann of Salt Lake City who achieved dramatic results with an engineer, badly burnt in a mining accident. The man suffered nightmares, endlessly relived the event and felt his scalp was burning. A week after one session of EMDR his symptoms had vanished. 'This operates according to principles we don't understand. It is like the early days of anti-depressants - it works but we don't know how,' he says. So how can flicking the eyes back and forth catapult someone into vividly reliving - and rapidly resolving - traumas that may have ruled their lives for 20 years? Supporters reason that if horrifying experiences can alter brain pathways in microseconds, why shouldn't they be healed as quickly?

Dr Shapiro says: 'Traumatic memories are like unlearnt lessons locked in the brain by the surge of neurochemicals that occur at times of great stress. These undigested experiences can remain for years tied up in their own biochemical package, impervious to later experiences. Somehow the eye movement unties the package and reconnects the isolated section to the rest of the brain.'

Some support for this idea comes from what is known about dreaming, which seems to be about processing information. While people dream their eyes flick back and forth, just like a patient watching the therapist's finger. But the theory is hardly conclusive. Dr Shapiro has obtained successful results by tapping her hands on the chair or playing alternating tones into the client's headphones.

Other psychologists claim that EMDR is only a modern version of the hypnotist's swinging watch. And there may be dangers. One critic is Professor Croydon Hammond at the University of Utah School of Medicine. He is one of several researchers who claim to have found no benefit from EMDR and warns that, used on patients with multiple personality disorders, it could make them worse.

Psychology is no less prone to fads than any other discipline. Behaviourism, primal screaming, and many other therapies have all been touted as the answer in the past. But somehow the miraculous early results are never duplicated and they end up being just one more method that works with some people and not with others. Whether EMDR will go that way is too early to tell. What is certain is that at the moment, it is hot.

For details about the conference, contact John Spector at Watford General Hospital (0923 244366)