Researchers performed several experiments with egg yolks both inside and outside the shell to better understand the physics of soft matter deformation in order to learn more about concussions, finding that "decelerational rotational impact" may be most harmful to the brain, according to findings published in Physics of Fluids. "We hope to apply the lessons learned from it to the study of brain biomechanics as well as other physical processes that involve soft capsules in a liquid environment, such as red blood cells," said study author Qianhong Wu.