A new study conducted by researchers at the University of California Davis Health (USA) reveals that human brain It’s getting bigger and bigger. The researchers hypothesis is that increased brain size may lead to increased brain reservepotentially reducing the overall risk of age-related dementias.
Specifically, study participants born in the 1970s had 6.6 percent more brain volume and almost 15 percent more brain surface area than those born in the 1930s.
“The decade in which you are born appears to influence brain size and, potentially, long-term brain health,” said the first author of the study, Charles DeCarli, which has been published in the journal ‘JAMA Neurology’.
DeCarli is a professor of neurology and director of the UC Davis Alzheimer’s Disease Research Center. “Genetics plays an important role in determining brain size, but Our findings indicate that external influences – such as health, social, cultural and educational factors – can also influence“added the specialist.
Researchers used magnetic resonance imaging (MRI) of the brains of participants in the Framingham Heart Study (FHS). This community study began in 1948 in Framingham, Massachusetts, to analyze patterns of cardiovascular and other diseases.
The original cohort consisted of 5,209 men and women between 30 and 62 years old. The research has continued for 75 years and now includes the second and third generations of participants.
The MRIs were performed between 1999 and 2019 with FHS participants born between the years 1930 and 1970. The brain study consisted of 3,226 participants (53% women, 47% men) with an average age of around 57 years at the time. of magnetic resonance imaging.
Increased brain size
The research, led by UC Davis, compared MRI scans of people born in the 1930s with those born in the 1970s. Gradual but steady increases were seen in several brain structures. For example, one measure looking at brain volume (intracranial volume) showed steady increases decade after decade.
For participants born in the 1930s, the average volume was 1,234 milliliters, but for those born in the 1970s, the volume was 1,321 milliliters, or 6.6 percent more volume.
Cortical surface area – a measure of the brain’s surface area – showed an even greater increase decade after decade.
Participants born in the 1970s had an average surface area of 2,104 square centimeters, compared to 2,056 square centimeters for participants born in the 1930s – almost 15 percent more volume.
Researchers found that brain structures such as white matter, gray matter, and the hippocampus (a brain region involved in learning and memory) They also increased in size when comparing participants born in the 1930s with those born in the 1970s..
Bigger brain may mean lower incidence of dementia
According to the Alzheimer’s Association, about 7 million Americans currently suffer from Alzheimer’s disease. That number is expected to rise to 11.2 million by 2040.
Although the numbers are increasing with the aging of the American population, the incidence of Alzheimer’s – the percentage of the population affected by the disease – is decreasing. A previous study found a 20 percent reduction in the incidence of dementia per decade since the 1970s.
“Larger brain structures, such as those observed in our study, may reflect better brain development and health. A larger brain structure represents greater brain reserve and may buffer the late effects of age-related brain diseases, such as Alzheimer’s and other related dementias,” says DeCarli.
One of the study’s strengths is its design, which allows researchers to examine brain images from three generations of participants with birth dates spanning nearly 80 years. One limitation is that non-Hispanic white participants make up the majority of the FHS cohort, which is not representative of the US population.
Source: EUROPA PRESS
