The smarter the person, the faster information zips around the brain, a UCLA study finds. The study, published in the Journal of Neuroscience, looked at the brains and intelligence of 92 people. All the participants took standard IQ tests. Then the researchers studied their brains using a technique called diffusion tensor imaging, or DTI.via NPR
DTI is a variant of magnetic resonance imaging (MRI) that can measure the structural integrity of the brain's white matter, which is made up of cells that carry nerve impulses from one part of the brain to another. The greater the structural integrity, the faster nerve impulses travel.
The team was able to figure this out because the 92 people in their study were all twins. Some were identical twins, who share all the same genes. Others were non-identical twins, who share only certain genes.
By comparing the groups, the researchers were able to tease out genes associated with the structural integrity of white matter. And it turned out many of these genes were also associated with intelligence.