Brain maps may trace early signs of disorder

NORTHWESTERN (US)—Computer-analyzed measurements of the brain’s topography—its unique dips, swells, and crevasses—may lead to early diagnosis of mental disorders, increasing the likelihood of effective treatment.

John Csernansky, chair of psychiatry and behavioral sciences at Northwestern University, says magnetic resonance imaging, or MRI, measurements that produce a map of the brain can provide the first scientific tool to gauge how brains of humans with and without mental disorders differ from each other and the time frame over which those differences develop.

In the past, comparing MRI brain maps was painstaking work. A technician would use a light pen to trace and manually measure the boundaries of brain structures.

“It was very laborious and you had to have an expert in your laboratory,” Csernansky explains. Now he is teaching computers to do the work, speeding the process and enhancing accuracy.

Currently, diagnosing psychiatric disorders is more art than science, says Csernansky. Unlike a heart attack, which can be identified with an EKG and a blood test for cardiac enzymes, psychiatric illness is diagnosed by asking a patient about his symptoms and history.

“That’s akin to diagnosing a heart attack by asking people when their pain came and where it was located,” Csernansky says. “We would like to have the same kinds of tools that every other field of medicine has.”

Schizophrenia usually starts in the late teens or early 20s and affects about 1 percent of the population. If the disease is caught early and treated with the most effective antipsychotic medications and psychotherapy, the patient has the best chance for recovery, but currently, treatment is only evaluated on whether the patients’ symptoms improve over several months.

Because psychotic and mood disorders are lifelong illnesses that require management throughout a person’s life, a longer view is necessary, Csernansky says.

“What we want to know is whether a few years later are you more able to work, are you better able to return to school?” he says. “If you take these medicines for years at a time, is your life better than if you had not taken them? We want to understand the effects of the medicines we give on the biological progression of the disease. We think that’s what ultimately determines how well someone does.”

Csernansky is recruiting 100 new subjects, half with early-stage schizophrenia and half who are healthy, to measure and map their brain topography and compare the differences and changes over two years as part of a study funded by the National Institutes of Health.

“The brain is very plastic and is constantly remodeling itself. Any changes we see in a disease has to be compared in a background of normal changes of brain structures,” he explains.

He notes that a brain map of schizophrenia would enable doctors to make the diagnosis with more confidence as well as catch it earlier.

“Like every other illness, psychiatric illnesses don’t blossom in their full form overnight. They come on gradually,” he says. “You don’t need a biomarker to tell you that you have breast cancer, if you can feel a tumor that is the size of a golf ball. But who wants to discover an illness that advanced? A biomarker of the schizophrenic brain structure would help us define it, especially in cases where the symptoms are mild or fleeting.”

Csernansky has previously shown that the brains of schizophrenic patients have abnormalities in the shape and asymmetry of the hippocampus, a part of the brain that is critical to spatial learning and awareness, navigation, and memory.

“Understanding what changes in brain structure occur very early in the course of schizophrenia and how medication may or may not affect these structures as time goes by will help us reduce the uncertainty of psychiatric diagnosis and improve the selection of treatments,” Csernansky explains.

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