While some signs can suggest if a person is at risk for developing schizophrenia, a definitive diagnosis is not determined until the fist psychotic episode occurs. But neuroscientists have now discovered an abnormal brain pattern that is linked to the development of schizophrenia.
Schizophrenia is a brain disorder that produces hallucinations, delusions, and cognitive impairments. The disorder usually becomes evident during adolescence or young adulthood. The new research is expected to fuel studies that test use of cognitive behavioral therapy and neural feedback as early interventions to combat the symptoms of schizophrenia.
In the new study, MIT neuroscientists working with researchers at Beth Israel Deaconess Medical Center, Brigham and Women’s Hospital, and the Shanghai Mental Health Center have now identified a pattern of brain activity correlated with development of schizophrenia.
The researchers believe the discovery of the abnormal brain pattern be used as a marker to diagnose schizophrenia earlier.
“You can consider this pattern to be a risk factor. If we use these types of brain measurements, then maybe we can predict a little bit better who will end up developing psychosis, and that may also help tailor interventions,” said Dr. Guusje Collin, lead author of the paper.
The study, which appears in the journal Molecular Psychiatry, was performed at the Shanghai Mental Health Center.
Researchers explain that before an individual experiences a psychotic episode — characterized by sudden changes in behavior and a loss of touch with reality — people can experience milder symptoms such as disordered thinking.
This kind of thinking can lead to behaviors such as jumping from topic to topic at random, or giving answers unrelated to the original question. Previous studies have shown that about 25 percent of people who experience these early symptoms go on to develop schizophrenia.
The researchers followed 158 people between the ages of 13 and 34 who were identified as high-risk because they had experienced early symptoms. The team also included 93 control subjects, who did not have any risk factors.
At the beginning of the study, the researchers used functional magnetic resonance imaging (fMRI) to measure a type of brain activity involving “resting state networks.” Resting state networks consist of brain regions that preferentially connect with and communicate with each other when the brain is not performing any particular cognitive task.
“We were interested in looking at the intrinsic functional architecture of the brain to see if we could detect early aberrant brain connectivity or networks in individuals who are in the clinically high-risk phase of the disorder,” Whitfield-Gabrieli says.
One year after the initial scans, 23 of the high-risk patients had experienced a psychotic episode and were diagnosed with schizophrenia. In those patients’ scans, taken before their diagnosis, the researchers found a distinctive pattern of activity that was different from the healthy control subjects and the at-risk subjects who had not developed psychosis.
The researchers discovered that in most people, a part of the brain known as the superior temporal gyrus — involved in auditory processing — is highly connected to brain regions involved in sensory perception and motor control.
However, in patients who developed psychosis, the superior temporal gyrus became more connected to limbic regions, which are involved in processing emotions. This could help explain why patients with schizophrenia usually experience auditory hallucinations, the researchers say.
Meanwhile, the high-risk subjects who did not develop psychosis showed network connectivity nearly identical to that of the healthy subjects.
Researchers believe this type of distinctive brain activity could be useful as an early indicator of schizophrenia, especially since it is possible that it could be seen in even younger patients.