According to an international team led by neuroscientists from the University of Pittsburgh School of Medicine and Maastricht University in the Netherlands, subtle differences in brain shape present in adolescence are associated with the development of psychosis .
In the results published today in JAMA Psychiatry, the differences are too subtle to be detected in an individual or used for diagnostic purposes. But the findings could contribute to ongoing efforts to develop a cumulative risk score for psychosis that would allow for earlier detection and treatment, as well as targeted therapies. The discovery was made with the greatest pooling of brain scans in children and young adults determined by psychiatric assessment to be at high risk for developing psychosis.
“These results were, in a sense, disappointing,” said Maria Jalbrzikowski, Ph.D., assistant professor of psychiatry at Pitt. “On the one hand, our data set includes 600% more high-risk youth who have developed psychosis than any existing study, which allows us to see statistically significant findings on brain structure. is so small that it would be impossible to see a difference at the individual level. More work is needed to translate our results into clinical care. “
Psychosis is an umbrella term for a constellation of serious mental disorders that make people have a hard time figuring out what is real and what is not. Most often, people have hallucinations where they see or hear things that others cannot see. They can also have deeply held beliefs or delusions, even when most people don’t believe them. Schizophrenia is only a disorder associated with psychosis, and psychotic symptoms can occur in other psychiatric disorders, such as bipolar disorder, depression, body dysmorphic disorder, or post-traumatic stress disorder. In people who are diagnosed with psychosis, there is great heterogeneity of results over time.
Diagnosis typically occurs in late adolescence and early adulthood, but more often symptoms begin to appear in adolescence, when clinicians can use psychological assessments to determine risk for a person to develop full-fledged psychosis.
Jalbrzikowsi and Dennis Hernaus, Ph.D., Assistant Professor in the School of Mental Health and Neurosciences at Maastricht University, are Co-Chairs of the Enhancing Neuro Imaging Genetics Through Meta-Analysis (ENIGMA) Clinical High Risk Clinical Working Group for Psychosis. This group pooled structural magnetic resonance imaging (MRI) scans of 3,169 volunteer participants with an average age of 21 years who were recruited from 31 different institutions. About half – 1,792 of the participants – were judged to be “at high clinical risk for developing psychosis.” Of these high-risk participants, 253 developed psychosis within two years. The Co-Chairs stressed that this study would not be possible without the collaborative efforts of the more than 100 researchers involved.
Looking at all the scans together, the team found that people at high risk for psychosis had significantly less cortical thickness, a measure of the thickness of the gray matter in the brain. In high-risk youth who later developed psychosis, a thinner cortex was more pronounced in several temporal and frontal regions.
Everyone goes through a process of cortical thinning as they become adults, but the team found that in younger participants between the ages of 12 and 16 who developed psychosis, thinning was already present. These high-risk youth who developed psychosis also progressed at a slower rate than in the control group.
“We don’t yet know exactly what that means, but adolescence is a critical time in a child’s life – it is a time of opportunity to take risks and explore, but also a time of vulnerability.” , Jalbrzikowski said. “We could see the result of something that happened even earlier in brain development, but doesn’t start to influence behavior until this stage of development.”
Hernaus pointed out that these findings underscore the importance of early detection and intervention in people who have risk factors for developing psychosis, including hearing the whispering voices that are not there and a family history of psychosis. .
“So far, researchers have mainly studied how the brains of people at high clinical risk for psychosis differ at any given time,” Hernaus said. “An important next step is to better understand changes in the brain over time, which may provide new clues about the underlying mechanisms relevant to psychosis.”
This research received the support of many donors listed in the JAMA Psychiatry manuscript. Jalbrzikowski received support from National Institute of Mental Health grant K01 MH112774.