Does Brain Size Matter?
More money, bigger houses, and faster cars. We live in a world where bigger is better. At least for most things.
When it comes to brains, we may make the same connection. Bigger brains equals more power.
You can bet this is the type of question that scientists would throw some funding at. As it turns out, the answer isn’t as clear cut as you might think.
So does brain size matter? More specifically, is brain size related to intelligence? Let’s take a look at what they’ve uncovered.
Size and Intelligence
A team of researchers, led by the University of Vienna, decided to take a stab at this question.
Using current brain imaging technology they performed a meta-analytic review. Basically, a study that collected and analyzed results from other research . In all, the data included over 8,000 different subjects.
They found that the association between brain volume and IQ was weak. Even when they adjusted for factors like age and gender. If you’re curious about the details, their findings have been published in the journal Neuroscience and Biobehavioral Reviews.
Yes and No
You could say, technically, that there is a statistical association. Even though it is weak.
Jakob Pietschnig is one of the lead authors on the paper. He had this to say:
“The presently observed association means that brain volume plays only a minor role in explaining IQ test performance in humans. Although a certain association is observable, brain volume appears to be of only little practical relevance.”
So what does matter?
It appears there might be a couple of other factors that give us humans our cognitive prowess. Jakob continues:
“Rather, brain structure and integrity appear to be more important as a biological foundation of IQ, whilst brain size works as one of many compensatory mechanisms of cognitive functions.”
Size and Structure
What is Jakob talking about here?
Looking simply at brain size doesn’t give us the whole story.
Let’s compare our brains against other species. By pure size, the sperm whale wins out. When looking at ratio of body to brain size, it’s the shrew.
Anthropologists have even found that the Neandertal brain was about 10% bigger than our modern brains.
When comparing brain size among the genders, males have been found to have bigger brains. But when you compare global IQ scores between men and women there is no difference.
However, when you look at the structure of the brain you begin to see differences. Findings from other research have pointed out that IQ is more heavily related to gray matter in certain areas. Specifically, it’s gray matter volume itself and volume in the frontal lobes that may give us greater intelligence.
There is also evidence between intelligence and white matter. The integrity of our white matter allows our brain regions to communicate with one another. The efficiency of those connections has been linked with upticks in intelligence.
The Real Question
So does brain size matter?
From an intelligence point of view, no. Not really. There’s a weak association, but it seems that our real cognitive abilities come from the structure of our brain and how well it communicates.
There’s also something to be said about how we use our brains. People sometimes over-emphasize the importance of large IQ.s. Even intelligent people are subject to cognitive biases, blunders, and errors in logic.
So the more important question is this:
What are you doing with the brain power you have?