Summary: People often say you are only as old as you feel. This may be the case for the aging brain. Researchers say older people who feel younger than their age have increased gray matter volume in key brain regions, fewer signs of brain aging and performed better on cognitive tests than those who felt their actual age.
While everyone gets older, not everyone feels their age. A recent study finds that such feelings, called subjective age, may reflect brain aging. Using MRI brain scans, researchers found that elderly people who feel younger than their age show fewer signs of brain aging, compared with those who feel their age or older than their age. Published in open-access journal Frontiers in Aging Neuroscience, this study is the first to find a link between subjective age and brain aging. The results suggest that elderly people who feel older than their age should consider caring for their brain health.
We tend to think of aging as a fixed process, where our bodies and minds change steadily. However, the passing years affect everyone differently. How old we feel, which is called our subjective age, also varies between people — with many feeling older or younger than their actual age.
But is subjective age just a feeling or attitude, or does it reflect how our bodies are actually aging? This question intrigued Dr Jeanyung Chey of Seoul National University in Korea.
“Why do some people feel younger or older than their real age?” asks Chey. “Some possibilities include depressive states, personality differences or physical health. However, no-one had investigated brain aging processes as a possible reason for differences in subjective age.”
People frequently experience some cognitive impairment as they age. In fact, the brain shows a variety of age-related changes that are reflective of declining neural health, including reductions in gray matter volumes. Recently developed techniques can help researchers to identify brain features associated with aging, to provide an estimated brain age.
Chey and her colleagues applied these techniques to investigate the link between subjective age and brain aging. They performed MRI brain scans in 68 healthy people whose ages ranged from 59-84 years and looked at gray matter volumes in various brain regions. The participants also completed a survey, which included questions on whether they felt older or younger than their age and questions assessing their cognitive abilities and perceptions of their overall health.
People who felt younger than their age were more likely to score higher on a memory test, considered their health to be better and were less likely to report depressive symptoms. Critically, those who felt younger than their age showed increased gray matter volume in key brain regions. The researchers used the MRI data to calculate estimated brain ages for the participants.
“We found that people who feel younger have the structural characteristics of a younger brain,” said Chey. “Importantly, this difference remains robust even when other possible factors, including personality, subjective health, depressive symptoms, or cognitive functions, are accounted for.”
The researchers hypothesize that those who feel older may be able to sense the aging process in their brain, as their loss of gray matter may make cognitive tasks more challenging.
However, at present the researchers do not know for sure if these brain characteristics are directly responsible for subjective age and will need to carry out long-term studies to understand this link further.
One intriguing possibility is that those who feel younger are more likely to lead a more physically and mentally active life, which could cause improvements in brain health. However, for those who feel older, the opposite could be true.
“If somebody feels older than their age, it could be sign for them to evaluate their lifestyle, habits and activities that could contribute to brain aging and take measures to better care for their brain health,” said Chey.
The research is part of a special article collection on assessment of brain aging across the lifespan.
Funding: This work was supported by the National Research Foundation of Korea, Korean Ministry of Education, Science and Technology, AMOREPACIFIC Foundation.
Source: Emma Duncan – Frontiers
Publisher: Organized by NeuroscienceNews.com.
Image Source: NeuroscienceNews.com image is in the public domain.
Original Research: Open access research for “Feeling How Old I Am: Subjective Age Is Associated With Estimated Brain Age” by Seyul Kwak, Hairin Kim, Jeanyung Chey and Yoosik Youm in Frontiers in Aging Neuroscience. Published June 7 2018.
Feeling How Old I Am: Subjective Age Is Associated With Estimated Brain Age
While the aging process is a universal phenomenon, people perceive and experience one’s aging considerably differently. Subjective age (SA), referring to how individuals experience themselves as younger or older than their actual age, has been highlighted as an important predictor of late-life health outcomes. However, it is unclear whether and how SA is associated with the neurobiological process of aging. In this study, 68 healthy older adults underwent a SA survey and magnetic resonance imaging (MRI) scans. T1-weighted brain images of open-access datasets were utilized to construct a model for age prediction. We utilized both voxel-based morphometry (VBM) and age-prediction modeling techniques to explore whether the three groups of SA (i.e., feels younger, same, or older than actual age) differed in their regional gray matter (GM) volumes, and predicted brain age. The results showed that elderly individuals who perceived themselves as younger than their real age showed not only larger GM volume in the inferior frontal gyrus and the superior temporal gyrus, but also younger predicted brain age. Our findings suggest that subjective experience of aging is closely related to the process of brain aging and underscores the neurobiological mechanisms of SA as an important marker of late-life neurocognitive health.