image: Brain structural (MRI) scans from a selection of individuals from the Lothian Birth Cohort 1936 taken during Wave 2 (when all participants were about 73 years old). Panel A shows global atrophy (brain volumetric shrinkage) ordered from least (top left) to most (bottom right). Panel B shows total white matter hyperintensity volume (increasing from top left to bottom right). Panels A and B are reproduced from Cox and Deary (2022) in Brain Aging, 2, 100032 (74); this article is an open access article distributed under the terms of the Creative Commons CC BY 4.0 license and the figure is reproduced here, with thanks, under that
license. Panel C shows white matter pathways of a middle-aged male adult, identified using diffusion MRI. Views from left to right: superior, lateral, anterior, inferior.
Credit: Ian J. Deary
Edinburgh, Scotland, 7 November 2024 – A groundbreaking 25-year research program has unveiled key insights into how our brains age and what factors influence cognitive performance throughout life. The findings, published on 7 November 2024 in Genomic Psychiatry, draw from the Lothian Birth Cohorts (LBC) studies, which uniquely tracked participants' cognitive abilities from childhood through their eighth decade of life.
Professor Ian Deary and Dr. Simon Cox from the University of Edinburgh present remarkable discoveries that challenge conventional wisdom about brain aging. Their research reveals that approximately half of the variance in intelligence test scores in older age can be traced back to childhood cognitive ability – a finding that raises intriguing questions about the nature versus nurture debate in cognitive development.
"What's particularly fascinating is that even after seven decades, we found correlations of about 0.7 between childhood and older-age cognitive scores," explains Professor Deary. "This means that just under half of the variance in intelligence in older age was already present at age 11."
Key findings include:
• Brain aging varies dramatically between individuals of the same age
• DNA methylation patterns can predict mortality risk
• Higher childhood intelligence correlates with better survival rates
• Genetics influences intelligence differently in childhood versus older age
The study's unique strength lies in its use of the Scottish Mental Surveys of 1932 and 1947, which tested almost every child born in 1921 and 1936 in Scotland. This comprehensive baseline allowed researchers to track cognitive changes across entire lifespans, revealing patterns previously hidden from science.
Some of the most intriguing findings relate to brain structure and function. Using advanced imaging techniques, the researchers demonstrated substantial variations in brain health among people of the same age. This raises important questions about what factors contribute to these differences and whether they might be modifiable through lifestyle interventions.
The research also challenges several preconceptions about cognitive aging. "We've learned that what we often assume are 'causes' of cognitive decline in older age are sometimes actually 'outcomes' of earlier cognitive differences," notes Dr. Cox. "This fundamentally changes how we think about brain health interventions."
The findings point to several crucial areas for future investigation:
• How does early-life cognitive ability influence lifestyle choices that affect brain health?
• What role do environmental factors play in maintaining cognitive abilities?
• Can interventions in midlife help preserve cognitive function in later years?
The full Genomic Psychiatry peer-reviewed article “Lessons we learned from the Lothian Birth Cohorts of 1921 and 1936,” is available on 7 November 2024 in Genomic Psychiatry. The article is freely available online at https://url.genomicpress.com/546yyhuy.
About Genomic Psychiatry – Genomic Psychiatry: Advancing Science from Genes to Society (ISSN: 2997-2388) represents a paradigm shift in genetics journals by interweaving advances in genomics and genetics with progress in all other areas of contemporary psychiatry. Genomic Psychiatry publishes peer-reviewed papers of the highest quality from any area within the continuum that goes from genes and molecules to neuroscience, clinical psychiatry, and public health.
Method of Research
Literature review
Subject of Research
People
Article Title
Lessons we learned from the Lothian Birth Cohorts of 1921 and 1936
Article Publication Date
7-Nov-2024
COI Statement
The authors have confirmed that no conflict of interest exists.