Though treatment can control the illness in more than half of patients, little is known about what actually causes the disorder - which affects about one in every 100 persons
worldwide - and how it affects the mind.
UCLA researchers may have just unraveled part of the mystery. Using magnetic resonance imaging, or MRI, and a new analysis technique, they have created the first images showing the toll the disease takes on the brain. The results are reported in the Proceedings of the National Academy of Sciences.
Throughout the five-year study, the researchers performed brain scans every two years on a group of 34 teenagers. The study population was made up of clinically diagnosed schizophrenics taking antipsychotic medications, another group of patients taking the same medications for mood disorders, and normal teens. The schizophrenic patients were diagnosed with the illness before adolescence, an unusual group that represents about 5 percent of all schizophrenic patients.
The images that resulted from the study "stunned" the scientists, according to lead researcher Paul Thompson. Rather than small, gradual changes, Thompson and his colleagues noted a dramatic wave of destruction of the gray matter in brain tissue of schizophrenic patients. Thompson described the wave as moving across the brain "like a forest fire."
While the healthy teens lost an average of 1 percent of gray matter per year, the schizophrenic patients lost up to 5 percent a year, with loss greatest among individuals with the most severe symptoms.
Study Important, But No Direct Therapy Yet
Additionally, the movement of tissue loss across the brain seemed to be in sync with the appearance of disease symptoms that would originate in those parts of the brain.
Starting off in the brain's logic center, the parietal cortex, tissue loss continued at a dramatic rate into the auditory part of the brain and then onto motor areas. Thompson says this sequence corresponds with the typical course of the disease. The first signs include confused or illogical thinking. As the illness progresses, more bizarre symptoms such as psychosis (unusual perceptions) and hallucinations occur.
"The study represents another step forward in our understanding of schizophrenia," says Dr. Steve Lamberti, associate professor of psychiatry at the University of Rochester Medical Center.
Lamberti says the strength of the study is the detail on the nature of deterioration and progression of the illness in young people, and the evidence that brain changes were not related to antipsychotic medications but to the disease process itself.
Though experts acknowledge the importance of the study's findings, they say it is limited for now. "Though there is no direct therapy application at this point ... there is a window of hope here." says Dr. Robert Freedman, Chairman of the Department of Psychiatry and the University of Colorado Health Sciences College.
"Most of us thought the damage was done in utero," says Freedman, but "the study suggests the changes can possibly be observed during adolescence."
Freedman calls the study groundbreaking as it has "opened up a window to a very complicated piece of biology that none of us completely understand." Yet, he says, "A lot of work still has to be done." 
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