Project Summary This proposal for an NINDS Diversity Administrative Supplement is to support Bluyé DeMessie, who is enrolled in the Einstein MD-PhD program. The supplement application includes a detailed plan for mentoring, training, and career development, ultimately leading to the achievement of the PhD, with a focus on human neuroscience in the area of sport-related brain injury. The mentoring and training program is centered on a supplementee research project, which is highly integrated with the parent R01 project, but explores novel aspects not addressed by the parent project aims, and in fact not addressed in the scientific field in general. Specifically, the project will (1) Determine how cerebral blood flow is changed by exposure to repetitive head impacts in sports (2) Assess how individual personal characteristics modify the relationship of repetitive head impacts with cognitive dysfunction. An additional key goal of this Supplement Proposal is for the supplementee to write and submit an F31 pre-doctoral NRSA Fellowship application to support his continued graduate work, culminating in the MD-PhD. Development of the F31 proposal is highly integrated into the timeline of the Supplement Proposal training plan.