In a new study, researchers took a “birds-eye view” into the brain to examine how its large-scale systems interact with one another, in order to gain a better understanding of the causes and symptoms of severe mental disorders including bipolar disorder, schizophrenia and depression.
The findings, published in the Proceedings of the National Academy of Sciences, shed new light on the similarities and differences in these three mental illnesses.
Lead researcher Justin T. Baker, M.D., Ph.D., scientific director of the McLean Institute for Technology in Psychiatry explains that the work is based on connectomics, the concept of “measuring all connections in the brain at the same time.”
“For most studies, illnesses are studied in isolation, but evidence strongly suggests that distinct psychiatric diagnoses are not separated by clear neurobiological boundaries,” said Baker.
“The approach we’ve taken is to look at the whole brain so you can see not only how individual systems like the visual system and motor system are functioning, but how higher order systems like cognitive systems are functioning in the brain to see if there are correlations.”
For the study, researchers from McLean Hospital in Massachusetts and Yale University looked at functional magnetic resonance imaging (fMRI) data from more than 1,000 individuals, including patients who had been diagnosed with bipolar disorder, schizophrenia and depression.
Information was collected through rest scans, in which participants were asked to simply lie in a scanner with their eyes open, allowing researchers to capture data about spontaneous fluctuations in the brain.
This approach allowed for “brain fingerprinting” to address “what changes in the brain are shared across illnesses and what aspects might be specific to different illnesses,” said Baker. “This work points to evidence at a high level that there are very pronounced changes in the brain that could start to serve as an objective biomarker.”
The findings are significant, said Baker, as there are no objective measures of psychiatric illnesses that can verify a patient’s reports regarding their symptoms.
Previous research suggests there is a significant genetic risk for schizophrenia and bipolar disorder and that these conditions affect certain parts of the brain. But this study highlights how one system is affected or disrupted as a function of how severe the illness is, irrespective of whether it is psychosis or depression.
The researchers plan to build on this work through studies into the functioning of large-scale brain systems related to OCD and trauma and longer-term investigations.
“We want to see if there is a fingerprint for different conditions and then use that information and apply it to the individual,” said Baker. “We are conducting studies that follow individuals over time to look at the brain to see how symptoms are changing.
“We’re trying to go from the snapshot view of these biomarkers to something that is much more dynamic and captures changes and nuances.”
Source: McLean Hospital