Comparing the human brain inside our skulls to a soft egg yolk floating around in an egg white might make our most vital organ seem unbearably fragile — but that's exactly what a group of scientists from the University of Pennsylvania has done.
In order to study what happens to the human brain during a traumatic brain injury or concussion, the team used an egg in place of the human brain, Science Alert reports.
The experiments — outlined in a study in Physics of Fluids — started with an idea born out of the kitchen: "critical thinking, along with simple experiments within the kitchen, led to a series of systematic studies to examine the mechanisms that cause egg yolk deformation," explained biomedical engineer Qianhong Wu from Villanova University in Pennsylvania.
Though the method was certainly unusual, the study helped the researchers gain a better understanding of the way soft matter, such as brain tissue, moves and deforms when influenced by outside forces.
Such knowledge can help to produce better safety gear for vehicles and can even help sports players avoid brain injuries.
Subjecting egg yolks to three types of impacts
Inside our skulls, the brain rests in a shock-absorbing fluid called cerebrospinal fluid.
In their experiments, the researchers started out by measuring the material characteristics of an egg yolk and its outer membrane, which they used as a stand-in for a real human brain.
This allowed them to measure the way the yolk reacted to impacts during their lab experiments.
The eggs were cracked open, and the yolks were placed in a clear container in which they were subjected to three types of impact as part of the experiments.
Adding to our knowledge of brain trauma
During the experiments, the team observed how the egg yolks deformed and stretched with a rotational impact, and how they barely changed with a direct blow to the plastic containers in which they were placed.
"We suspect that rotational, especially [decelerating] rotational, impact is more harmful to brain matter," said Wu.
The results of the test correlate with previous research involving crash tests and pendulum head impacts. The new findings add weight to the theory that the brain is more sensitive to rotational movement than it is to linear motion.
Of course, there is still a lot we do not know about brain injuries, and the way the brain reacts to trauma, and the researchers say linear motion is still an important metric that must be considered in future experiments.
In the meantime, this relatively simple experiment that has originated in the kitchen, adds to a growing knowledge that has the potential to help countless people affected by brain injuries.