Researchers say the brain doesn’t just change in youth and older age. Their study may have implications in mental health treatments.
Researchers can now accurately estimate your age by looking at an image of your brain.
That’s according to a recent study published in the journal Frontiers in Human Neuroscience.
By analyzing brain scans of healthy adult volunteers, scientists in China found that significant changes occur in the brain from early to middle adulthood.
This research contradicts the long-held theory that the brain structure remains relatively stable during this period.
While most neuroscientific research has focused on the rapid changes in the brain that occur in early and later life, this study concludes that our brains continue to change throughout our lifespans.
The brain and age
Images showing these structural changes provided the researchers a model for age estimation.
This was based on identification of specific brain regions where changes occur that are highly correlative with age.
The researchers hope to access results of a long-term study, as the brain images they used were only snapshots of individual brains taken at a single moment.
Even so, they determined that the brain regions that showed the earliest changes had previously been associated with cognitive decline in old age, such as decreased reaction times, reasoning abilities, and memory.
That our brains continue to change throughout early adulthood may have ramifications for attitudes about drug use — namely, that drug use during this stage of life could still negatively affect brain development.
Marijuana use, for instance, can affect brain development for adults as old as 25 —particularly in individuals prone to mental illness.
“Individuals are most vulnerable to developing major disorders such as schizophrenia between 16 and 25,” Dr. Heather Whalley, a researcher at the Center for Clinical Brain Sciences, at the University of Edinburgh, told Healthline. “Individuals with a propensity for schizophrenia are more likely to be ill if they smoke marijuana. This period of early adulthood is a vulnerable time with the brain developing, including the development of higher-order cognitive regions. If that development is interrupted, the eventual maturity is different than if the individual hadn’t taken the drugs.”
The effects of illness
Additional research into the structures of adult brains could also provide insight into the effects of illness on the brain and hopefully determine causation vs. consequence.
Currently, brain images can show evidence of mental illness, but not time of onset.
“In terms of depression, we’re seeing changes in the brain structure, but not when they happen,” Whalley said. “The changes themselves could be causing the depression, conversely, depression could be causing damage to the brain structure.”
“What we need to do is have larger studies and collect longitudinal data to see scans of individuals’ brains a couple years apart and how these correspond to symptoms or mood changes,” Whalley added. “But imaging is very expensive, so it’s difficult to do significantly large studies to find something clinically useful.”
Still, studies like this one can advance the understanding of mental illness, and potentially prevention and treatment.
“We know that some parts of the brains in individuals with depression are aging faster than those of their well counterparts,” Whalley said. “With the aging of the brain comes a decline in cognition, slowed processing — with various diseases associated with age like dementia as the extreme. But this decline also feeds into depression.”
“It’s useful to know from a disease perspective whether someone’s biological age is better or worse than their chronological age,” she added. “This study could help determine what the norm of the brain should be at a certain age, so we could then understand how a diseased brain deviates from that norm. Or we could see a positive deviation and look into what’s helping them age successfully.”
The scans the researchers analyzed were captured using Diffusion Tensor Imaging (DTI), an MRI-based imaging technique that makes it possible to estimate the location, orientation, and anisotropy (a change in physical property based on direction) of the brain’s white matter tracts.
“The biggest application of DTI is to look at the organization of the brain, how the structures change with age, and how things change in disease,” Dr. Stephan Maier, a professor of radiology and image processing at Gothenburg University in Sweden, told Healthline. “How the brain is organized was known before but only through autopsy. But nothing was possible to do in vivo before DTI.”