For 10 years Claire* heard voices shouting and telling her she was no good, as well as ordering her to buy alcohol and cigarettes.
"When I was hearing voices I just didn't like myself at all, or like my life, I hated my life," Claire told the BBC.
"I wanted to end it, I wanted to kill myself. I mean if I could have got a gun I think I would have shot myself, it was so bad."
The medication Claire was prescribed made life bearable but the voice did not stop. Three years of psychotherapy didn't silence it either. In fact, Claire wondered if talking about the voice actually made it worse.
Claire had run out of conventional options for dealing with her voice when she was put in contact with Professor Julian Leff from University College London.
Professor Leff, who worked with patients with schizophrenia for 37 years, had come up with a new method for helping patients with voices.
He planned to ask patients to build avatars of their tormentors, selecting voices and faces using customised software.
"The idea was that if we give the invisible entity a human face then it can be much easier for the patient to converse with it," Professor Leff told the BBC.
"The point is that because you created it you know it can't harm you. And therefore, you can say things to it that you wouldn't dare to say back to the voice."
Via a computer link, Professor Leff spoke to patients from another room entirely. Over the course of up to six therapy sessions Professor Leff played the role of both the avatar and the therapist.
When speaking as the avatar, Professor Leff's custom-built software altered his voice.
"In the first session the avatar has to identify itself in the patient's mind with the voice. So it starts saying the horrible things," Professor Leff explained.
In his normal voice he can then support the patient to stand up to the voice.
"I encourage the patient, saying you mustn't put up with this, you must tell the avatar that what he or she is saying is nonsense, you don't believe these things, he or she must go away, leave you alone, you don't need this kind of torment.
"In the next few sessions the avatar gradually changes to saying alright I'll leave you alone, I can see I've made your life a misery, how can I help you?"
By the end of their treatment, patients who completed the therapy reported that they heard the voices less often or were less distressed by them.
Levels of depression and suicidal thoughts also decreased; a particularly relevant outcome-measure in a patient group where one in 10 will attempt suicide.
For Claire, avatar therapy did not stop the voice entirely but it is now much quieter and her life has improved in many ways.
"I feel more at peace with myself obviously, and I'm not self-harming, my self-esteem has risen quite a lot. I can live more of a normal life now."
Claire's story of ineffective medication and therapy is not uncommon; one in four patients with schizophrenia find that their symptoms do not respond to medication.
And the auditory hallucinations can be one of the most debilitating symptoms of schizophrenia.
The voices can be bullying and unkind, telling patients to hurt themselves or, less commonly, to hurt other people.
Currently, cognitive-behaviour therapy (CBT) is the recommended treatment in the UK for patients with schizophrenia. For patients who hear voices, a short course of CBT includes showing them a variety of coping skills such as relaxation and methods for distracting themselves when the voice is present.
But Dr Rufus May, a clinical psychologist who specialises in hearing voices, says that ignoring the voices is missing the point.
He advocates entering into a dialogue with voices as well as patients.
"The voices are kind of ambassadors for emotional conflicts in people's lives," he said.
"We may succeed in silencing them with vast amounts of medication but we're actually then missing this opportunity for integration."
Mounting evidence suggests that childhood traumas, bullying and neglect are often the root cause of voice hearing.
Dr May emphasises the need to address those causes and understand why someone might be hearing voices.
Talking to the voices
For decades the doctrine from the professional psychiatric community was that voices like Claire's should be suppressed by medication and dismissed.
Professor Thomas Craig, from Kings College London Institute of Psychiatry, is a collaborator of Professor Leff, and will lead the large-scale trial of avatar therapy which begins next month at South London and Maudsley's Sharp clinic.
He remembers a time when even acknowledging the existence of the voices was seen as validation for something which was an invention of the mind.
"When I trained in psychiatry I was told you did not discuss in any great detail the content of people's voices and delusions.
"And that's radically changed with the new therapies now. The new cognitive therapies are all saying these people's experiences are real"
Avatar therapy is just one of those new therapies.
Dr Rufus May suggests that avatar therapy could open the gateway to other approaches involving a dialogue with voices.
But he urges caution about developing therapy which requires sophisticated equipment which may not be widely available.
"We've been doing such things, role plays, in hearing voices groups. And that seems a lot more cost effective.
"You can use puppets, you can use chairs, or you can directly interview the voice with the person acting as the spokesperson."
*Name changed to protect identity.