This Faculty Early Career Development Program (CAREER) award supports a research and education program that improves the understanding of how head impacts and traumatic events cause brain injury in humans and animals. Traumatic brain injury is a major cause of long-term disability and economic burden in the United States. However, brain injuries often occur at microscopic scales that cannot be seen in living humans, limiting efforts to understand and prevent them. This project will develop detailed digital models of human and animal brains to examine how features such as brain shape, folding patterns, and nerve fiber pathways influence where injuries occur and how they spread through the brain. The project will advance scientific understanding of brain injury and help inform the development of more effective protective strategies for the general population. It will also support the design of animal studies that better reflect human injury, reducing the need for new animal testing in alignment with current efforts by United States science agencies and regulators. The project includes educational activities that use brain models, public exhibits, and teacher training to engage learners, support workforce development in science and engineering, and promote broad access to scientific knowledge. The goal of this project is to determine how structural differences in brains across species, influence mechanical responses and injury thresholds under head loading. The research advances fundamental biomechanics and mechanobiology by explicitly linking brain structure to tissue-level deformation and injury mechanisms. The project will develop high-resolution, species-specific computational brain models that capture regional anatomy, cortical folding, and white-matter fiber architecture derived from medical imaging data. These models will be validated and used to simulate head impacts from controlled animal experiments as well as reconstructed or recorded human head impacts.