New insights on how early intelligence predicts brain ageing
In the latest publication from Genomic Psychiatry, scientists at the University of Edinburgh present the results of long-term research on brain ageing, spanning 11 to 82. These findings significantly alter our understanding of genetics' role in this process.
The research uncovered notable differences in the way individuals' brains age, both structurally and functionally. More than half of the variability in intelligence among older adults is due to genetic predispositions, reflecting differences already evident in childhood.
Prof. Ian Deary, the author of the study, highlights, "What's particularly fascinating is that even after seven decades, we found correlations of about 0.7 between childhood and older-age cognitive scores." This implies that slightly less than half of the variation in intelligence in older age was already apparent at age 11.
The researchers also observed that genes operate differently in childhood compared to old age. Individuals who are more intelligent in their youth tend to live longer, and the risk of mortality is connected to changes in the activity of specific genes.
Scottish research challenges previous beliefs
The project drew upon data from unique Scottish studies carried out in 1932 and 1947, encompassing nearly all children born in 1921 and 1936. This extensive database allowed researchers to track cognitive changes throughout the participants' lives, uncovering patterns previously inaccessible to science.
The study's findings prompt consideration of which factors influence brain ageing and whether they can be modified through lifestyle interventions. Scientists plan to explore how cognitive abilities in childhood impact lifestyle choices, the role of environmental factors in maintaining cognitive abilities, and whether interventions during middle age can help preserve cognitive function in later life.
Dr. Simon Cox says we have learned that what we often perceive as causes of cognitive decline in older age is actually the result of earlier differences. This fundamentally changes our approach to brain health interventions.
