(July 7, 2015) Have
you ever wondered why the human brain evolved the way it did?
A new study by Northeastern physicist Dmitri Krioukov and
his colleagues suggests an answer: to expedite the transfer of information
from one brain region to another, enabling us to operate at peak capacity.
The paper, published in the July 3 issue of Nature
Communications, reveals that the structure of the human brain has an
almost ideal network of connections—the links that permit information to
travel from, say, the auditory cortex (responsible for hearing) to the motor
cortex (responsible for movement) so we can do everything from raise our
hand in class in response to a question to rock out to the beat of The 1975.
The findings represent more than a confirmation of our
evolutionary progress. They could have important implications for
pinpointing the cause of neurological disorders and eventually
developing therapies to treat them.
“An optimal network in the brain would have the smallest
number of connections possible, to minimize cost, and at the same time it
would have maximum navigability—that is, the most direct pathways for routing
signals from any possible source to any possible destination,” says
Krioukov. It’s a balance, he explains, raising and lowering his hands to
indicate a scale. The study presents a new strategy to find the connections
that achieve that balance or, as he puts it, “the sweet spot.”