LOS ANGELES: A recent study has revealed younger generations have bigger brains, and they are continuing to get larger, which could be reducing the risk of overall age-related dementia. The study was conducted by researchers at the American academic health centre UC Davis Health and published in the medical journal JAMA Neurology, found participants born in the 1970s had 6.6 per cent larger brain volumes and approximately 15 per cent larger brain surface area than those born in the 1930s.
Charles DeCarli, the study’s lead author, who is a professor of neurology and the director of the UC Davis Alzheimer’s Disease Research Centre, highlighted the significance of birth decade on brain size and long-term brain health. He emphasized that while genetics play a major role in determining brain size, external influences such as health, social, cultural, and educational factors may also contribute.
DeCarli explained that larger brain structures observed in the study may indicate improved brain development and overall brain health. This larger brain reserve could potentially buffer the late-life effects of age-related brain diseases like Alzheimer’s and related dementias.
MRI scans were conducted on participants born between the 1930s and the 1970s between 1999 and 2019. A total of 3,226 participants, with 53 percent female and 47 percent male, participated in the study, with an average age of 57 at the time of their MRI.
The results revealed consistent increases in several brain structures over successive decades. For instance, brain volume showed steady increases decade by decade. Participants born in the 1970s had an average volume of 1,321ml compared to 1,234ml for those born in the 1930s, marking a greater volume of 6.6 percent.
Similarly, cortical surface area, a measure of the brain’s surface, showed a substantial rise. Participants born in the 1970s had an average surface area of 2,104cm2 compared to 2,056cm2 for those born in the 1930s, representing an almost 15 percent increase. Additionally, brain structures such as white matter, grey matter, and the hippocampus, a brain region involved in learning and memory, also increased in size between the two groups.
