Information flows in brain like well-defined travel routes

Just as most of the world's air travel passes through a few major hubs, the majority of information in the brain flows through similarly well-travelled routes, a team led by an Indian-origin researcher from Indiana University has found.

According to the team, 70 percent of all information within cortical regions in the brain passes through only 20 percent of these regions' neurons.

"The discovery of this small but information-rich subset of neurons within cortical regions suggests this sub-network might play a vital role in communication, learning and memory," said Sunny Nigam, Ph.D. candidate in the IU Bloomington College of Arts and Sciences' Department of Physics and lead author on the study.

These high-traffic "hub neurons" could play a role in understanding brain health since this sort of highly efficient network is also more vulnerable to disruption.

"The brain seems to favour efficiency over vulnerability," said John M. Beggs, associate professor of biophysics in a paper appeared the journal Neuroscience.

To conduct the study, scientists recorded small electrical impulses from up to 500 neurons from a part of the brain responsible for the sense of touch.

"This is the first study to combine such a large number of neurons with such high temporal resolution," Nigam added.

The experiments, conducted in live and tissue samples, were based in rodents.

Similar high-traffic zones in the cortex have been shown to exist in more advanced mammals, including primates and adult humans.

Understanding how the brain maintains good "air traffic control" between information-rich and information-poor neurons will be the next step in unraveling the mystery of hub neurons.

"If we ever want to understand how these types of neurons keep information in our heads flowing smoothly, we really need to learn a lot more about how they work together," Nigam noted.