Researchers at the Harvard University including an Indian-origin scientist have replicated a folding human brain in 3D, revealing for the first time a simple mechanical framework for how it folds.

Understanding how the brain folds could help unlock its inner workings and unravel brain-related disorders as function often follows form.

It shows that while many molecular processes are important in determining cellular events, what ultimately causes the brain to fold is a simple mechanical instability associated with buckling.

Highly folded brains are seen only in a handful of species including some primates, dolphins, elephants and pigs.

In humans, folding begins in fetal brains around the 20th week of gestation and is completed only when the child is about a year and a half.

“We found that we could mimic cortical folding using a very simple physical principle and get results qualitatively similar to what we see in real fetal brains,” said L. Mahadevan, professor of applied mathematics, organismic and evolutionary biology and physics from Harvard John A. Paulson School of Engineering and Applied Sciences.

The number, size, shape and position of neuronal cells during brain growth all lead to the expansion of the gray matter, known as the cortex, relative to the underlying white matter.