Brain development

Continues into adulthood says new study

Biology News

Cross section of human brain showing white matter

Human brain development doesn't stop at adolescence, but continues well into our 20s, demonstrates recent research from the Faculty of Medicine & Dentistry at the University of Alberta.

It has been a long-held belief that the human brain stopped developing in adolescence. But now there is evidence that this is not the case, according to medical research conducted in the Department of Biomedical Engineering by researcher Christian Beaulieu, an Alberta Innovates – Health Solutions scientist, and by his PhD student, Catherine Lebel.

"This is the first long-range study, using a type of imaging that looks at brain wiring, to show that in the white matter there are still structural changes happening during young adulthood," says Lebel. "The white matter is the wiring of the brain; it connects different regions to facilitate cognitive abilities. So the connections are strengthening as we age in young adulthood."

The findings appear in the Journal of Neuroscience. For their research they used magnetic resonance imaging or MRIs to scan the brains of 103 healthy people between the ages of five and 32. Each study subject was scanned at least twice, with a total of 221 scans being conducted overall. The study demonstrated that parts of the brain continue to develop post-adolescence within individual subjects.

The research results revealed that young adult brains were continuing to develop wiring to the frontal lobe; tracts responsible for complex cognitive tasks such as inhibition, high-level functioning and attention.

In some people involved in the study, several tracts showed reductions in white matter integrity over time, which is associated with the brain degrading. The researchers speculated in their article that this observation needs to be further studied because it may provide a better understanding of the relationship between psychiatric disorders and brain structure. These disorders typically develop in adolescence or young adulthood.

"What's interesting is a lot of psychiatric illness and other disorders emerge during adolescence, so ... if certain tracts start to degenerate too soon, it may not be responsible for these disorders, but it may be one of the factors that makes someone more susceptible to developing these disorders," says Beaulieu.

"It's nice to provide insight into what the brain is doing in a healthy control population and then use that as a springboard so others can ask questions about how different clinical disorders like psychiatric disease and neurological disease may be linked to brain structure as the brain progresses with age."