A potential marker for schizophrenia manifests itself in key brain areas well before the debilitating disease that afflicts 1 percent of the world’s population begins, usually manifesting itself in young adulthood, according to a new study, published online Aug. 12 in the journal, JAMA Psychiatry, and reported in Bioscience Technology
. The Yale University study shows that schizophrenia is “associated with marked alterations in connections between the thalamus, a major relay system in the brain, and the frontal cortex, which is involved in higher-level cognitive functions."
Alan Anticevic, assistant professor of psychiatry and lead author of the paper, explained, “Up until this study, we did not know whether this pattern was a result of the disease or a potential byproduct of medication or some other factor. We show these same abnormalities already exist in people who are at higher risk for developing psychosis.”
According to Tyrone Cannon, professor of psychology and senior author of the study, while schizophrenia often develops late in adolescence or early adulthood, it is usually presaged by some early warning signs, including “mild suspicion, a perception that outside stimuli carry a special personal significance or hearing a voice calling the individual’s name.” If chronic schizophrenia is not treated, the symptoms get worse and can become debilitating. Scientists are uncertain about which brain mechanisms cause its onset.
The international multi-site study included whole-brain functional connectivity maps of 243 people who had early warning symptoms and 154 healthy subjects. They were followed for two years. Researchers discovered “a decrease in functional connectivity between the thalamus and prefrontal cortex regions in the at-risk group that was particularly pronounced in those who went on to develop full psychosis.” The at-risk group “had excess connectivity between thalamus and sensory areas of the brain.” The researchers explained that the pattern viewed during the early stages of heightened risk looked like the changes noted in more chronic patients.
While Cannon believes that additional research must be done to definitively cite disrupted functional connectivity between the thalamus and frontal cortex as a cause of schizophrenia, he said that the Yale research findings are in line with the concept that people who develop schizophrenia “experience an excessive reduction in synaptic connections between brain cells that normally occur during adolescence.”
Schizophrenia is a serious disorder of the mind and brain but it is also highly treatable. Although there is no cure for schizophrenia, the treatment success rate with antipsychotic medications can be high. If the appropriate level of investment is made in research, it had been estimated that a cure for schizophrenia could be found by 2013. However, schizophrenia has only received a small fraction of the amount of medical research dollars that go into other serious diseases and disorders, according to Schizophrenia.com