The prevailing explanation for the brain’s crenellations is that they increase computational capacity by packing a large surface area into a small space. Exactly how this works is a matter of speculation, but abnormalities have been linked to disorders like autism and depression.
In a paper published online Monday in the Journal of Biomechanics, researchers simulated the effects of trauma on three-dimensional computer models of normal and wrinkle-free brains. In the smooth models, almost every brain structure, from brain stem to frontal lobe, was more vulnerable to damage. Our brains appear to have a built-in crumple zone.
The results should improve models of traumatic impacts used to design protective headgear and investigate injury. In the meantime, the protective effect of the wrinkles, known technically as sulci, doesn’t mean cognitive explanations are incorrect. The two features are complementary, a testament to the exquisite piece of evolutionary engineering that is the brain.