It moved across the brain like a forest fire, destroying more tissue as the disease progressed

Professor Paul Thompson, UCLA

However, in schizophrenics, they detected accelerated grey matter loss - over six years, the patients lost 10% in the parietal region.

In addition, this destructive process spread to other parts of the brain, with areas such as the temporal lobe, and areas which control the senses and movement - particularly eye movement, particularly affected.

The brain fields responsible for eye movement lost as much as 5% of their grey matter a year.

These findings would tally with many of the symptoms, such as involuntary eye movement, frequently felt by schizophrenics.

Professor Paul Thompson, at UCLA, said: "This is the first study to visualise how schizophrenia develops in the brain.

"Scientists have been perplexed about how schizophrenia progresses and whether there are any physical changes in the brain.

"It moved across the brain like a forest fire, destroying more tissue as the disease progressed."

Hope for early test

Patients who had the worst tissue loss also suffered the worst schizophrenic symptoms, and the doctors are excited about how this "time-lapse" MRI scanning has uncovered distinct physical changes which can be linked to the disease.

They say the knowledge might be used to help spot schizophrenia patients early so that treatment can be given.

However, at the moment, there are no medications which address the rapid loss of brain tissue.

The research was published in the journal the Proceedings of the National Academy of Sciences.