Schizophrenia is elusive. In spite of decades of using brain scans, computer models and other sophisticated tools, there are many questions to be answered. How does it evolve? What does the brain look like when it functions abnormally? What is the relationship between structure and function? What other factors - age, disease, injury and so on - might contribute to schizophrenia?
An international team of scientists has discovered structural brain abnormalities in patients with schizophrenia, offering clues as to how the disease could develop and respond to treatment modalities. In analyzing brain MRI scans from 2,028 schizophrenia patients and 2,540 healthy controls, these scientists performed the biggest structural brain meta-analysis yet for schizophrenia. The study was conducted at more than a dozen U.S. and European locations.
Published in Molecular Psychiatry, the results come from the Schizophrenia Working Group in the Enhancing Neuroimaging Genetics through Meta-Analysis (ENIGMA) project, which is co-chaired by Jessica Turner, associate professor of psychology and neuroscience at Georgia State, and Theo van Erp, assistant professor of psychiatry and human behavior at the University of California, Irvine (UCI). The scientists found that individuals with schizophrenia had smaller hippocampus, amygdala, thalamus, accumbens and intracranial volumes than control participants. They also determined that people with schizophrenia had larger pallidum and ventricle volumes than the controls. These brain areas are responsible for memory, emotion and reward.
ENIGMA, which started in 2009, brings together brain researchers from 33 countries to study the brain. The organization's purpose is to share the huge amounts of brain scan data that are too big for one scientist to analyze alone and examine them to determine which genes or medications influence neurodegenerative and severe mental illnesses. The ENIGMA project collaborations include working groups for other mental disorders such as major depression, ADHD, autism, bipolar disorder and addiction.
Van Erp, who earned his Ph.D. from the University of Utrecht in Utrecht, The Netherlands, in 2007, stated that the next steps are to compare structural data across disorders to identify which brain region is most affected in each and to determine the effects of various factors. As he said, "This collaborative work of 58 researchers marks a new era of open team science in applying neuroimaging methods to address questions in severe mental illness, such as schizophrenia," van Erp said.
Van Erp added that the next step is to compare structural data across disorders to identify which brain region is the most affected in which disorder, to determine the effects of genetic variation, environmental factors, age and medication and the similarities in symptoms between disorders. "Ultimately, our advances in knowledge must lead to better treatment outcomes for patients, their families, and society as a whole," he said.