Human Brain Size Increase May Have A Shocking Result
Compared to individuals who served in World War II and those who awaited their return, recent research indicates that the average human brain size has increased by 6.6%. Additionally, modern brains exhibit approximately a 15% increase in surface area.
These findings suggest a potential advantage for contemporary humans in combating neurodegenerative diseases like dementia, which often correlate with brain shrinkage.
The study, conducted by a team at UC Davis, analyzed brain changes over 75 years across generations. Dr. Charles DeCarli, the director of the UC Davis Alzheimer’s Disease Research Center, notes that larger brain structures observed in the study may signify enhanced brain development and health, potentially serving as a buffer against age-related brain diseases.
Published in JAMA Neurology, the study utilized brain magnetic resonance imaging (MRIs) from participants in the Framingham Heart Study conducted between 1999 and 2019. This ongoing study, initiated in 1948, examines cardiovascular and other diseases among participants spanning multiple generations.
Dr. DeCarli highlights the impact of birth decade on brain size and long-term health, stating that life choices, such as those related to health, social activity, and education, may influence brain size.
The study, involving 3,226 participants with an average age of around 57 at the time of the MRI, revealed consistent increases in several brain structures over time. For instance, individuals born in the 1970s exhibited a 6.6% greater brain volume compared to those born in the 1930s. Moreover, cortical surface area increased by nearly 15% over the same period.
Despite the growing elderly population in the United States, the incidence of Alzheimer’s disease is decreasing, which may be partly attributed to improved brain health and size. A prior study reported a 20% reduction in dementia incidence per decade since the 1970s.
I really want to know what caused this change. Hopefully they will do more research on it. Also, I would expect that bigger brains would make you smarter. Unfortunately, I can’t say I have seen any real-life evidence for that… 😉