In a recent study, investigators from the University of Missouri discovered that brain scans, coupled with behavioral data, could provide markers for diagnosing psychosis risk.
Moreover, the researchers discovered that improving how well people at risk for psychosis learn from positive and negative feedback could potentially help mitigate psychotic symptoms.
Psychotic disorders such as schizophrenia and bipolar disorder often involve delusions or hallucinations in which people lose touch with reality.
Researchers hope findings will help mental health professionals to understand how to better treat their patients with psychoses and prevent its onset.
“Around the time Nobel Prize winner John Nash first developed psychosis he turned down an endowed chair at the University of Chicago because he said he believed he was going to become the emperor of Antarctica, despite the population of Antarctica being zero,” said Dr. John G. Kerns, a professor of psychological sciences.
“How a genius like John Nash could develop a delusion has long baffled clinicians and scientists. We wanted to examine whether dysfunction in a brain region called the striatum and a disruption in feedback-based learning were related to risk for psychosis.”
Investigators discovered feedback-based learning helps learners raise their awareness of strengths and weaknesses and identify actions to be taken to improve.
This learning technique is heavily dependent on varying levels of dopamine, a neurotransmitter that sends signals to other nerve cells in a part of the brain called the striatum.
Dopamine in the striatum provides an important teaching signal that increases or decreases the chance that certain thoughts and actions occur again in the future.
In research conducted at the Mizzou Brain Imaging Center and using a feedback-based learning task, Kerns and his team found that people at risk for psychosis are impaired when they need to rely on feedback to learn.
Using functional magnetic resonance imaging (fMRI), the team found that people at risk for psychosis failed to activate the striatum when they received feedback.
“Current research suggests that people like John Nash develop delusions in part because they have problems learning from feedback, like a car driving without a brake,” Kerns said.
“Our research is also consistent with other research that people with psychosis have an increased level of dopamine in the striatum. However, for the first time we have linked psychosis risk to both a behavioral impairment, poor feedback learning, as well as striatum dysfunction.”
It is also hoped that this research will be useful in detecting risk for psychosis, Kerns said.
Measuring dopamine in the striatum is both invasive and expensive and cannot be done in routine clinical assessment.
However, Kerns found that non-invasive measures can be used in everyday clinical practice to effectively detect striatal dysfunction. Ultimately, Kerns believes this research will help professionals both detect risk and prevent psychosis, which could mean decreased suffering for many people and their families.
The study appears in the Schizophrenia Bulletin.
Source: University of Missouri