- 300 brain MRIs mapped against Allen Brain Atlas.
- Supercomputer analysis finds thinner cortex and myelin in adolescent brains.
- Brain maps find genetic links to schizophrenia.
Think of your brain as an airport terminal. Electrical impulses, hormones, blood, oxygen, and thoughts stream through like the thousands of passengers teeming at Heathrow, O'Hare, or JFK.
Some airports serve larger distribution patterns; others travel only locally or from a small hub to a larger regional hub. So, too, your brain, says Kirstie Whitaker, neuroimaging researcher at the University of Cambridge.
Since many of the first bouts of depression, anxiety, and psychosis occur during the teenage years, Whitaker and a team from the Neuroscience in Psychiatry Network (NSPN) led by Ed Bullmore set out to understand brain development in adolescence.
“We seek to provide meaningful insights that will improve treatment and prevention interventions for the millions of young people who experience psychiatric disorders,” says Whitaker.
Supplementing our knowledge about the origins of mental disease can only serve to relieve the public health burden, she adds.
To understand the biological underpinnings of mental health disorders, Bullmore's team looked at 300 subjects between the ages of 14 and 24. Using magnetic resonance imaging (MRI) scans, they built a network showing the strength of connectivity between various hubs in the brain.
The scientists then compared the MRIs with the four terabytes of brain map data available in the Allen Brain Atlas, a one-of-a-kind, central repository for anatomic and genomic brain information. To complete their analysis, they looked to the Darwin supercomputer at Cambridge.
As the team reports in the Proceedings of the National Academy of the Sciences (PNAS), these hubs are still not permanently established in adolescence.
Knowing what happens in the run-up to the emergence of mental health disorders gives us the chance to build interventions and treatments that might prevent them in the future. ~Kirstie Whitaker.
The outer layer of the brain (cortex) continues to thin until the middle of the third decade of life, and the insulation around nerve connections (myelin) is also still being layered on during this segment of life. Myelin strengthens and speeds the ability to transmit nerve signals between hubs.
“Linking our MRIs with the heroic work that the Allen Institute has performed measuring the expression of 20,000 genes at hundreds of regions across the brain gives us a result that simply couldn’t have happened if the Allen data weren’t available for open use,” says Petra Vertes, postdoctoral researcher in the Brain Mapping Unit (BMU) at Cambridge University and study co-author.
More importantly, these still evolving regions hold genes linked to a risk of schizophrenia. Comparing MRIs of people who have been diagnosed with schizophrenia would be a logical next research step, says Vertes.
The NSPN now looks to explore changes in individual brains over time. They’ve asked their volunteers to come back for a second MRI a year after their first to see if differences in brain development relates to their life experiences.
The NSPN team is also inviting people who are at high risk of developing depression to come in for MRI scans.
“Our next big question will be whether we can identify differences in their brain structure and function before symptoms of depression occur,” Whitaker says. “Knowing what happens in the run-up to the emergence of mental health disorders gives us the chance to build interventions and treatments that might prevent them in the future.”
In all, Whitaker and her team are pleased with their findings and have made them publically available. Their MRI data can be found here.
“We’ve benefited from the work of others,” says Whitaker. “We’re excited to see the innovations that will occur as a result of researchers taking a look at what we did and extending it with their own ideas.”