The human brain is getting bigger in size. Why this is good news for dementia patients

The human brain is expanding over time, research suggests. (Representational Image: Harvard Health)

Recent groundbreaking research suggests that our brains might be expanding over time, potentially offering a defense against age-related dementia. The study, led by scientists at UC Davis Health, unearthed compelling evidence pointing to a notable surge in brain volume and surface area among individuals born in the 1970s compared to those born in the 1930s.

Published in JAMA Neurology in March, these findings not only underscore the impact of genetics on brain size but also shed light on the pivotal role played by external factors such as health, social dynamics, culture, and education.

Charles DeCarli, professor of neurology at UC Davis and the study's lead author, told New York Post, "Genetics plays a major role in determining brain size, but our findings indicate external influences — such as health, social, cultural, and educational factors — may also play a role."

The research, drawing from data sourced from the Framingham Heart Study, examined brain scans spanning generations, offering insights into the evolution of brain morphology and its potential implications for cognitive health.

Analysing MRI scans from individuals born between 1925 and 1968, with an average age of 57, the study uncovered a striking pattern of incremental growth in brain volume and surface area. The results revealed a noteworthy surge in brain volume, with individuals born in the 1970s boasting a 6.6% higher volume and a remarkable 15% greater surface area compared to their counterparts from the 1930s.

Moreover, the study identified significant expansions in gray matter, white matter, and the hippocampus, a crucial region associated with learning and memory retention.

Explaining the significance of these findings, DeCarli elucidated, "Larger brain structures like those observed in our study may reflect improved brain development and enhanced brain health."

This augmentation in brain size potentially signifies a larger brain reserve, which could serve as a defense against the onset and progression of age-related neurodegenerative diseases, including Alzheimer's and related dementias.

With an aging global populace and the prevalence of neurodegenerative disorders on the rise, the prospect of harnessing the innate resilience of growing brain structures offers a glimmer of hope in the quest for effective interventions and treatments.