Dutch researchers studying 80 children over a four-year period found that if hearing voices was treated as relatively "normal" and not strange or frightening, symptoms were likely to lessen.

The researchers Sandra Escher, Marius Romme and Alex Buiks are half-way through their study and will present their findings at mental health charity Mind's annual conference on Tuesday.

There have been few previous studies of children who hear voices, but only one has looked at the condition over a period of time.

It suggested that the severity of the disturbance caused by hearing voices worsened as the child got older.

However, the Dutch study says children in the second year of the research were more likely to have fewer symptoms and to need less psychiatric treatment.

The children are aged eight to 18.

Stress

The researchers said many of the voice-hearing experiences were triggered by stressful circumstances, such as sexual abuse, moving home or bereavement.

They believe that understanding the cause of the condition and dealing with it sensitively can reduce the symptoms dramatically.

They say the key to reducing symptoms appears to lie in whether the child and his or her parents try to "normalise" the condition and not make it seem frightening or strange.

According to Mind, 2% of children in all age groups hear voices, although there is very little research on the subject.

Accepting voices

It has traditionally been thought that hearing voices was a symptom of schizophrenia. Patients are usually prescribed tranquillisers.

However, Marius Romme, professor of social psychiatry at the University of Limburg, Maastricht, says: "We must accept that the voices exist. We must also accept that we cannot change the voices. They are not curable, just as you cannot cure left-handedness or homosexuality - human variations are not open to cure - only to coping.

"Therefore to assist people to cope we should not give them therapy that does not work. We should let people decide for themselves what helps or not. It takes time for people to accept that hearing voices is something that belongs to them."