Schizophrenics who are taught to put their delusions to the test go on to make speedier recoveries from acute psychosis than patients receiving more established therapies, according to a study co-authored by the professor of psychology at Birmingham University.
Max Birchwood said the findings of his study fly in the face of traditional thinking on treatment regimes for patients with severe psychosis.
He said: "When I did my training I was taught that it was not only unhelpful but also dangerous to speak to people about their psychotic symptoms because it would upset some inner equilibrium. We were told to give medication and wait. But we have challenged this idea."
In two papers published in the British Journal of Psychiatry, Professor Birchwood and his colleagues from Northern Birmingham Mental Health Trust describe a study of 69 patients who received treatment for acute psychotic thinking.
Of the half who received cognitive therapy, 95 per cent reported no hallucinations at a nine-months follow-up, compared with 44 per cent of the control group. Moderate or severe residual symptoms were shown by 5 per cent of the recipients of cognitive therapy versus 56 per cent of the other group.
And the Birmingham research suggests that old symptoms are not substituted by new ones, though treatment-resistant symptoms may persist.
Professor Birchwood believes that cognitive therapy works because "people with psychosis are trying to understand their chaotic mental life and want to talk about it desperately."
Cognitive therapists aim to identify with a patient's distress, taking their psychotic experiences at face value, discussing them without prejudice and breaking them down into smaller, more manageable bits - though the bits rarely add up.
The objective is to convince the patient to devise an empirical formula that will put his or her delusions to an unequivocal test.
For example, Professor Birchwood persuaded one patient who was convinced that the destiny of all British finances from the stock market to the price of milk lay in her hands, to take responsibility for the collapse of the economy by collecting supermarket receipts for milk purchases for two weeks. When prices did not change, she dropped her belief.
"Far from creating more problems we were surprised by how well received cognitive therapy was," said Professor Birchwood. He added: "Trust is the essence of this approach. We never turn round and say: 'I told you so, you're psychotic'."