Follow-aware
A study conducted by UC Davis Health researchers found that human brains increase in size over time.
The researchers discovered that the brain size of participants born in the 1970s was 6.6% larger, with a brain surface area approximately 15% larger, compared to those born in the 1930s.
“The decade in which someone is born appears to influence brain size and perhaps their long-term health,” said Charles DeCarli, the study’s first author. “Genetics plays a major role in determining brain size, but our findings suggest that external influences – such as factors… Health, social, cultural and educational – may also play a role.”
The researchers used magnetic resonance imaging (MRIs) data of the brains of participants in a study that began in 1948 in Framingham, Massachusetts, to analyze patterns of cardiovascular disease.
The study lasted for 75 years, and included 5,209 men and women between the ages of 30 and 62 years.
The study compared MRI images of people born in the 1930s with those born in the 1970s. Gradual but steady increases were found in several brain structures.
For example, a measurement that studied brain volume (the volume inside the skull) 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 about 6.6 percent larger in volume.
The cortical surface area (a measure of the brain’s surface) has increased more and more decade after decade. The average brain surface area of participants born in the 1970s was 2,104 square centimetres, compared to 2,056 square centimeters for participants born in the 1930s.
The researchers found that brain structures, such as white matter, gray matter and the hippocampus, also increased in size when comparing participants born in the 1930s to those born in the 1970s.
“Larger brain structures may reflect improved brain development,” DeCarli said. “Larger brain structures represent a greater reserve that may mitigate the late effects of age-related brain diseases such as Alzheimer’s disease and related dementias.”
The study was published in JAMA Neurology.
Source: Medical Express