Philip Bayly has spent years trying to figure out the best way to jiggle a brain.
The mechanical engineer is part of a team of researchers at Washington University studying how a jolt to the head can shake the brain — the kind of injury a football player suffers when crashing into an opponent. Using a specially-designed device that vibrates volunteers’ heads, they hope to better understand the effects of repeated brain injuries.
Many people think of the brain as a hard ball bouncing inside your head, Bayly said, but it’s more like soft pink Jello tethered to your skull.
“Your brain doesn’t just rattle around loosely,” he said. “It’s connected to the skull by a really intricate system of membranes. I liken it to a bungee jumper, where the cord protects you from a dramatic collision.”
The membranes offer some cushion to the brain, but even a seemingly minor bump on the head can twist and deform the delicate organ. Repeated head injuries can lead to serious neurodegenerative diseases, including chronic traumatic encephalopathy.
Researchers do not recreate brain injuries in the lab because that would be unethical and unsafe for patients. But they can collect data on how the brain moves in response to slight vibrations and use it build mathematical simulations of head trauma, which Bayly calls “virtual crash tests.”