Subjective Age and Brain Aging: How Feeling Younger Impacts Brain Health

Estimated reading time: 4 minutes

• What is Subjective Age (SA)?
• Key Findings: Subjective Age and Brain Aging
• How Was the Study Conducted?
• Why Does Subjective Age Matter?
• Limitations and Future Research
• Conclusion
• Call to Action

Have you ever felt younger or older than your actual age? Research shows that subjective age (SA)—how old you feel compared to your chronological age—can have a significant impact on brain health and cognitive function. A groundbreaking study involving 68 healthy older adults explored the link between subjective age and brain aging, revealing fascinating insights into how our perceptions of aging influence our neurobiological health.

In this article, we’ll dive into the key findings of this research, the methods used, and what it means for understanding the connection between subjective age and brain aging.

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What is Subjective Age (SA)?

Subjective age (SA) refers to how old individuals feel compared to their actual chronological age. For example, a 70-year-old who feels like they are 60 has a younger subjective age. SA is more than just a psychological concept—it has been linked to health outcomes, cognitive performance, and even brain structure.

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Key Findings: Subjective Age and Brain Aging

The study, conducted by researchers using MRI scans and machine learning techniques, revealed several important findings:

1. Younger Subjective Age, Healthier Brain:
   • Participants who felt younger than their actual age had larger gray matter volumes in key brain regions, such as the hippocampus and prefrontal cortex.
   • These individuals also had a younger predicted brain age, suggesting slower brain aging.
2. Older Subjective Age, Faster Brain Aging:
   • Those who felt older than their chronological age showed signs of accelerated brain aging, including reduced gray matter volume and older predicted brain age.
3. Cognitive Performance:
   • Younger SA was associated with better cognitive performance, particularly in working memory and recall tasks.
   • Older SA was linked to cognitive decline and increased depressive symptoms.
4. Interoceptive Hypothesis:
   • The study supports the interoceptive hypothesis, which suggests that awareness of age-related changes (e.g., physical or cognitive decline) influences how individuals perceive their age.

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How Was the Study Conducted?

The research involved the following steps:

1. Participants:
   • 68 healthy older adults from the Korean Social Life, Health, and Aging Project (KSHAP).
   • Participants were divided into three groups based on their subjective age: younger, same, or older than their actual age.
2. Cognitive Tests:
   • Tests included the Mini-Mental State Examination (MMSE), California Verbal Learning Test, and working memory tasks.
3. Brain Imaging:
   • MRI scans were used to analyze brain structure using voxel-based morphometry (VBM).
   • A machine learning model was developed to predict brain age based on MRI data.
4. Statistical Analysis:
   • Researchers compared brain structure and predicted brain age across the three SA groups.
   • They also examined the role of health, personality traits, and depressive symptoms as potential mediators.

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Why Does Subjective Age Matter?

1. Brain Health:
   • Feeling younger is associated with healthier brain structures and slower brain aging.
   • Feeling older may indicate accelerated brain aging and increased risk of cognitive decline.
2. Cognitive Function:
   • Younger SA is linked to better memory, attention, and executive function.
   • Older SA is associated with cognitive inefficiency and higher cognitive effort.
3. Psychological Well-being:
   • Subjective age influences emotional states and self-perceptions, which can impact overall well-being.
4. Lifestyle Choices:
   • Individuals with a younger SA may adopt more active lifestyles, further benefiting brain health.

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Limitations and Future Research

While the study provides valuable insights, it has some limitations:

• The age-prediction model had lower accuracy for older adults.
• The sample may over-represent healthy older adults, limiting generalizability.
• Subjective age was measured using a single question, which may not capture the full complexity of age perception.

Future research should:

• Explore the neural mechanisms behind subjective age.
• Conduct longitudinal studies to understand the temporal relationship between SA and brain aging.
• Investigate the role of social influences and cultural factors in shaping subjective age.

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Conclusion

The study highlights the profound connection between subjective age and brain aging. Feeling younger than your actual age may be a sign of healthier brain structures and better cognitive function, while feeling older could indicate accelerated brain aging and cognitive decline. These findings underscore the importance of self-perceptions of aging in maintaining brain health and overall well-being.

By understanding the link between subjective age and brain aging, we can develop strategies to promote healthy aging and improve the quality of life for older adults.

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Call to Action

Interested in learning more about brain health and aging? Follow the latest research and share this article with friends and family to spread awareness about the importance of subjective age in maintaining cognitive health!

Citation: Kwak, S., Kim, H., Chey, J., & Youm, Y. (2018). Feeling how old I am: Subjective age is associated with estimated brain age. Frontiers in aging neuroscience, 10, 168.