MAGGIE is crying. Sitting in a chair, a plastic bag of shopping at her feet, she is weeping for her husband, who died two years ago. She can speak of her feelings only in a whisper. The lump in her throat will not go away.

This is not a bereavement centre, but the weekly voice clinic at Queen Mary's Hospital in Sidcup, Kent, the only NHS facility of its kind in the country.

Janet can barely make herself heard. Five years ago she was involved in a horrific road accident in which another vehicle ended up on top of her car. As well, in recent years, four friends or relatives have died from throat cancer. For six weeks after the accident Janet lost her voice completely.

Both women are among the 10 per cent of patients treated at the clinic who require psychological counselling to help them to overcome their vocal difficulties.

In Janet's case, the focus of her anxiety became her throat. Before her voice can be restored, her psychological problems will have to be resolved.

Sarah Harris, a speech therapist, is part of the four-person team at Sidcup. She works with her husband, Mr Tom Harris, an ear, nose and throat consultant; Jacob Lieberman, a psychotherapist and osteopath; and Dinah Harris, a former opera singer who provides voluntary voice coaching.

Mrs Harris says that voice problems are never entirely physical. 'It is unusual to find a completely psychological voice loss; usually it's a complicated combination of the physical and the psychological,' she says.

Since speech is the major means of communication, any loss of voice causes severe stress and can, in turn, affect a patient's ability to recover. 'You can almost always see physical damage and find there is a psychological element as well,' Mrs Harris says.

In cases of psychosomatic illness, people build barriers around themselves, which prevent emotional anxieties from being released. This leads to physiological damage, which can take the form of indigestion, heartburn or ulcers, or can affect the voice. 'It's largely a matter of individual preference which site you choose to base your problems,' she says.

'In many cases, patients are convinced it's purely a physiological problem. They don't see that if they block emotional pain, it can come out as physical pain. I've got one patient who is convinced that if he could just get rid of the pain in his throat, everything else in his life would be all right. He can't link the pain in his throat with the pain in his life.'

Mr Harris agrees: 'You rarely see a hysterical aphonic - someone who is glad that they have lost their voice because it gets them attention. I would say that all of these patients have some psychological problems.

'Sometimes we start working with a patient who has physical problems only to discover that there are also deep-rooted psychological reasons for their voice damage - such as being abused as a child,' he says.

In this vicious circle of psychological and physical damage, patients often say that they cannot speak properly because they feel as if they have a lump in the throat. Often damage is caused to the delicate folds of muscle known as the vocal cords. Damage also can be caused by excessive wear and tear, causing scarring, nodules and hard tissue. Without realising it, people may not close their vocal cords properly, resulting in a hoarse voice or whisper.

Voice problems that are predominantly psychological can sometimes be spotted because the patient, caught unawares, may cough or laugh quite normally.

Mr Harris will look for the physical damage inside the patients' throats using a tiny camera that projects an image on to a video screen. Sometimes surgery will be needed to repair swollen folds, or to remove nodules that have become hard and fibrous.

Mr Lieberman provides more examples. 'I've just been talking to a man who is pubophonic - in other words, even though he is in his twenties, his voice hasn't yet broken. With work, he can produce a low, adult voice, but in certain stressful situations, his voice once again becomes high-pitched.

'After a few sessions with him, it has become clear that he has some unresolved difficulties growing up and growing away from his parents. Unconsciously, his parents do not want to see their son growing into a separate entity, so they encourage his childish side and frown upon any adult behaviour.

'This means he has become divided between what he calls the 'nice' childlike side of him, the side his parents are happy with, and the other, more grown-up side,' he says.

The clinic's latest development is an occasional weekend workshop run by the psychologist Phiroze Neemuchwala that encourages patients to search for the emotional causes of their vocal problems.

'It's no accident that when we talk about feeling upset, we use the expressions 'feeling choked up', or 'feeling like there is a lump in the throat'. These are physical symptoms of an emotional problem,' Mr Neemuchwala says.

'I've just started working with a female teacher who needs to be able to command respect and foster discipline, but who finds herself incapable of raising her voice. After much talking, it turns out that her mother died when she was 12, leaving this woman to take care of her father and four brothers. She got it into her head that she had to be the perfect substitute for mum, the perfect little angel, and that meant never shouting or being cross.

'This woman has been heart-broken for the past 15 years, but has never been able to express her grief or anger, with the result that she has a block against raising her voice.'

Mr Neemuchwala says that teachers, actors and singers - people whose livelihoods depend on their voices - are particularly at risk from psychosomatic disorders.

'Sometimes the pressure of performing will create emotional stress which will strangle the voice,' he says. 'Sometimes a subconscious fear of rejection will make an actor strangulate his voice. It's easier to say, 'I failed the audition because my voice was off' than, 'I failed because I wasn't good enough.' '

Louis, a 25-year-old actor who attended the weekend course, says he began to experience problems with his voice at drama college. 'It was a competitive atmosphere, very stressful, and I was always being told that my voice was too tense. Of course, that only made things worse. I even lost my voice completely at the technical rehearsal for the final year show.

'In the end the college referred me to Tom and Sarah Harris, who told me I had a scar on my vocal cords. I was put on the waiting list for an operation. I also started seeing Jacob Lieberman, who helped me to see that even though there was a physiological problem, this was a symptom of a far deeper distress, rooted in my traumatic relationship with my parents and family,' he says.

'I think it was the stress of those unexplored feelings that was constricting my larynx. If I had the operation without looking at the underlying emotions, my vocal problems would just come back again.'

But for every satisfied patient, there are innumerable others who never receive the help they need and suffer in wordless silence. 'It's a struggle to find funding,' Mr Harris says. 'Voice is not a life-and-death field, so we tend to get overlooked when it comes to handouts. Society refuses to pay for quality of life. But the people we see here are suffering terribly - and they are just the tip of the iceberg. Someone has to help them.'