The average volume of the human brain has increased from 1,234 milliliters to 1,321 milliliters in 40 years.
- The average brain volume increased from 1,234 milliliters to 1,321 milliliters in 40 years, according to a new study.
- The average cortical surface area of people born in the 1970s was almost 15% larger than that of people born four decades earlier, from 2,056 to 2,104 square centimeters.
- The study also found that the size of the hippocampus – which is strongly associated with learning and memory – also appears to increase from decade to decade, as do the volumes of white and gray matter in the brain. .
New research has revealed that the size of the human brain has been increasing since the start of the 20th century. To arrive at this observation, scientists examined the brain scans of 3,226 people participating in the Framingham Heart Study (FHS). Launched in 1948 in the United States, the FHS study adds new participants every decade and now includes the children and grandchildren of certain members of the original cohort.
A 6.6% expansion in the average volume of human brains
By examining scans that were taken between 1999 and 2019, the study authors sought to compare the brains of people born in the 1930s to those of people born in the 1970s. They found that the average volume of the brain increased from 1,234 milliliters to 1,321 milliliters during this 40-year period, representing an expansion of approximately 6.6%.
The size of the participants’ brains saw an even greater increase: the average cortical surface area of people born in the 1970s was almost 15 percent larger than that of people born four decades earlier, increasing from 2,056 to 2,104 square centimeters.
Importantly, the study also found that the size of the hippocampus – which is strongly associated with learning and memory – also appears to increase from decade to decade, as do the volumes of white matter and matter. gray in the brain.
Increase in the size of the human brain: what impact on our health?
The director of the study, Charles De Carli, commented on these results in a press release stating that: “the decade in which one is born appears to have an impact on brain size.” The researcher also estimated that “While genetics play a major role in determining brain size, our results indicate that external influences – such as health, social, cultural and educational factors – may also be influential.”
The exact impact of our expanding brains on our long-term well-being remains to be determined, although the researchers note in their report that adult brain volume is “an important predictor of changes in cognition over time. Larger brain structures, like those observed in our study, may reflect better brain development and brain health. That may also buffer the effects of age-related brain diseases, such as Alzheimer’s disease and related dementias. concludes Charles De Carli, author of the study published in the journal JAMA Neurology.
