The greater the volume of gray matter in certain brain regions, the more intelligent the person is, suggests a study published online in NeuroImage.
Researchers from UC Irvine College of Medicine have correlated gray matter volume to intelligence. They reached this conclusion after analysing the structural images of the brain of 47 healthy adults. The participants also had to take standard IQ tests. the volume of gray matter was calculated based on a methodology known as voxel-based morphometry; these findings were then correlated with IQ scores.
We often hear of how big brains are indication of intelligence. Previous studies have found weak links between large brains and higher IQ. However, none of this actually constitute confirmation of this theory. The new study, on the other hand, is the first to show how gray matter located in specific brain regions, as opposed to overall size, is related to IQ.
Furthermore, many other regions are linked to IQ, and different combinations of these spots can also be the reason for IQ scores. This would mean that intelligence would depend on the individual pattern of gray pattern in one’s brain. Also, these areas are found throughout the brain, and thus, one “intelligence centre” is most likely not the actual case. This would adequately explain why two people having the same IQ might be good at different things: for instance, one might be good at maths, and not at spelling, while the situation would be the opposite for another person, while they both score the same for IQ.
Another interesting finding is that only around 6% of the gray matter present in the brain seems to be correlated with IQ. So, the efficiency of few structures would be related to intelligence, while the more gray matter, the more intelligent the person would be.
Why would some people have more gray matter than others, though? Sadly, the findings do not cover this relevant question. It might be a matter of genetics, as has hinted other studies: for instance, previous research suggests that the regional distribution of gray matter might be inheritable.