The complex link between brain size and intelligence - The Listener
People have long been tempted to link brain size and cognition. The intuitive notion that a “big brain” means “more intelligent” was first threatened some time. Nov 22, There is a commonly expressed view that mental abilities are linked to brain size in humans. Such a view is partially supported by gradual. stated that there is no relationship between brain size and intelligence in modern man, although a causal relationship when dif- ferent species are compared is.
Why are people's brains different sizes?
But that growth comes in myriad possible forms—growth from zygote to neonate to adult, growth in size or stature, growth of an entire species. Another form, growth in brain size, has long been linked to success.
A recent study in the Proceedings of the Royal Society B appears to suggest that, in a sampling of wild animals, average brain size—measured from craniums of museum specimens collected from urban and rural animals over the last century or so—is correlated with living around people. Both the city mouse of the white-footed variety and city vole of the meadow variety had larger cranial capacities than their rural cousins. The notion that brain size indicates cognitive prowess is, of course, flattering for us.
And the cranial capacity of two shrew species short-tailed and masked and two bats little brown and big brown grew bigger over the decades in rural, but not urban, settings. People have long been tempted to link brain size and cognition.
Perhaps it is the brain size relative to body size that makes our brains the biggest. Though humans come out well there, too, this measure is biased toward birds and other small animals that have relatively large brains for their bodies.
Consider, though, the strange case of that growing child. But one could argue that it is when this intense brain growth ends that the real growth of the child qua individual begins.
The next phase of brain development occurs in large part through an increase in synaptic pruning: Brain size, or the size of brain parts, can be a reasonable indicator of skill, to be sure. That hasn't stopped researchers from drawing conclusions, though.
Inpsychologist Michael McDaniel evaluated studies that used brain-imaging and standard intelligence tests and found that unequivocally, bigger brains correlated with smarter people [source: Since males have the bigger brains, they must have the smarts, right?
Brain Size and Intelligence: Does Size Matter? - Brain Size and Intelligence | HowStuffWorks
In one study, scientists converted the SAT scores ofand year-olds to a corresponding IQ score and found that males averaged 3. The study, did, however, use about 10, more females than males, which may have affected the average, but the study's authors believe that the greater the brain tissue, the greater the ability for cognitive processing [source: Remember those studies with twins on the last page?
In one study, after the scientists drew conclusions about the role of genetics in brain matter, they gave the twins intelligence tests. They found a link between intelligence and the amount of gray matter in the frontal lobes.
Neuroscience and intelligence - Wikipedia
Since frontal lobes appeared to be controlled by genetics, the results indicate that parents pass along the potential for genius. But should gals just throw up their arms, curse their parents and refuse to make sense of nuclear physics? You've got to go out and shake what your momma gave you. These areas may just lay the groundwork for intelligence down the line or indicate the potential for genius if a person works hard. Albert Einstein may be a perfect example that it may not be overall size that matters, but size of certain sections beyond just the frontal lobe.
It's also worth noting that the strangest things seem to increase brain size. Scientists have found that the brains of London's cab drivers enlarge and change as they learn complicated routes. Cab drivers who have been navigating the streets for years had significant structural changes, as they exhibited a larger posterior hippocampus and a slightly smaller front hippocampus [source: