Our brains do change from early to mid-adulthood

August 21, 2017, Frontiers
Credit: copyright American Heart Association

Scientists in China have found that significant microstructural changes occur in the brain from early to mid-adulthood, allowing them to accurately estimate an individual's age from their brain structure. The findings are striking, because until now scientists thought that brain structure was relatively stable during this period of adulthood.

Researchers have known for a while that our brains change as we age. From their initial maturation during childhood to their decline in old-age, numerous studies have demonstrated that our brains change over our lives in terms of their structure and activity.

Scientists have mostly focused on the rapid and profound brain changes that occur in early and late life and have largely neglected to study changes from early to mid-adulthood, assuming that our is relatively stable during this period.

"The changes in brain structure and function from early to mid-adulthood are largely unknown," explains Lixia Tian of the Beijing Jiaotong University, and an author on the study, which was recently published in Frontiers in Human Neuroscience. "The motivation for this study was to add to our knowledge about the changes in brain structure throughout the lifespan."

Because scientists have been unaware of how our brains change during this period of life, they don't routinely account for this when studying the brain, which could lead them to misinterpret their results. "In brain studies including adult subjects and covering a large age-span, scientists should consider possible age effects carefully. Otherwise, they could produce spurious results, possibly reflecting age effects, rather than the effect under investigation," explains Tian.

The team analyzed a publicly available dataset of brain scans from a group of healthy volunteers who had undergone , a specialized type of . Diffusion tensor imaging allows scientists to image and map structures in the brain and to measure parameters such as fractional anisotropy, a measurement based on the diameter, density and connectivity of nerve fibers in specific brain regions.

The researchers analyzed a sample of scans from 111 volunteers in early to mid-adulthood (18-55 years old). They found that fractional anisotropy significantly decreased with age, and identified specific brain regions where the earliest age-related changes occurred. The changes were so highly correlated with age that the researchers could estimate the age of an individual simply by analyzing their brain scan. This is striking, considering that prior to this, scientists had thought that the brain structure of healthy adults was relatively stable before old-age.

So, what do these changes mean? "Researchers have linked decreases in to degeneration of the human brain with disease or in old-age," says Tian. Although the structural changes were subtle compared with those previously reported in elderly people, the brain regions that showed the earliest changes have been associated with cognitive decline in old-age, such as decreased reaction times, reasoning abilities and memory.

The team did not directly investigate if the changes were linked to cognitive decline in these adults. These changes may represent some of the very first signs of the aging brain, but it is unclear if they coincide with the beginning of age-related .

One of the limitations of the study was that it provided just one snapshot of differences in brain structure over adulthood. The researchers would like to conduct a long-term study following the same people from early to mid-adulthood. "Such a longitudinal study may more accurately show microstructural changes in the human brain from early to mid-adulthood," explains Tian.

Explore further: Brain connectivity after 30 may predict psychological problems

More information: Lixia Tian et al, Microstructural Changes of the Human Brain from Early to Mid-Adulthood, Frontiers in Human Neuroscience (2017). DOI: 10.3389/fnhum.2017.00393

Related Stories

Brain connectivity after 30 may predict psychological problems

July 17, 2017
Underdevelopment of the brain network underlying inhibition—the ability to concentrate on a particular stimulus and tune out competing stimuli—after 30 years of age is associated with self-reported psychological problems, ...

Elderly yoginis have greater cortical thickness

July 13, 2017
Scientists in Brazil have imaged elderly female yoga practitioners' brains and found they have greater cortical thickness in the left prefrontal cortex, in brain areas associated with cognitive functions like attention and ...

Tiny molecule has big effect on brain's ability to learn

August 7, 2017
Prenatal brain development is a crucial period, and as new research has found, even small alterations to the way brain cells develop can have significant effects later in life.

Study describes changes to structural brain networks after radiotherapy for brain tumors

June 26, 2017
Researchers compared the thickness of brain cortex in patients with brain tumors before and after radiation therapy was applied and found significant dose-dependent changes in the structural properties of cortical neural ...

Poor adolescent diet may influence brain and behavior in adulthood

June 19, 2017
Adolescent male mice fed a diet lacking omega-3 fatty acids show increased anxiety-like behavior and worse performance on a memory task in adulthood, according to new research published in The Journal of Neuroscience. The ...

Study finds gray matter density increases during adolescence

May 26, 2017
For years, the common narrative in human developmental neuroimaging has been that gray matter in the brain - the tissue found in regions of the brain responsible for muscle control, sensory perception such as seeing and hearing, ...

Recommended for you

A peek into the interplay between sleep and wakefulness

July 20, 2018
Sleep is an autonomic process and is not always under our direct, voluntary control. Awake or asleep, we are basically under the regulation of two biological processes: sleep homeostasis, commonly known as 'sleep pressure', ...

Paralyzed mice with spinal cord injury made to walk again

July 19, 2018
Most people with spinal cord injury are paralyzed from the injury site down, even when the cord isn't completely severed. Why don't the spared portions of the spinal cord keep working? Researchers at Boston Children's Hospital ...

Neural inflammation plays critical role in stress-induced depression

July 19, 2018
A group of Japanese researchers has discovered that neural inflammation caused by the innate immune system plays an unexpectedly important role in stress-induced depression. This insight could potentially lead to the development ...

Scientists uncover the role of a protein in production and survival of myelin-forming cells

July 19, 2018
The nervous system is a complex organ that relies on a variety of biological players to ensure daily function of the human body. Myelin—a membrane produced by specialized glial cells—plays a critical role in protecting ...

Understanding the neuroscience of binge drinking

July 19, 2018
A new study from researchers at Columbia University Irving Medical Center found that binge drinking impairs working memory in the adolescent brain. The study, in mice, explains why teenagers who binge drink are 15 times more ...

Neurons can carry more than one signal at a time

July 18, 2018
Back in the early days of telecommunications, engineers devised a clever way to send multiple telephone calls through a single wire at the same time. Called time-division multiplexing, this technique rapidly switches between ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.