A study in Science Translational Medicine found that retired contact‑sport athletes showed persistent blood–brain barrier leakiness years after play, and that barrier disruption correlated with worse cognitive outcomes. Researchers scanned 47 retired contact athletes and compared them with controls; greater leakiness associated with memory and cognitive test deficits, implicating chronic neurovascular dysfunction as a downstream consequence of repeated head impacts. Authors recommend longitudinal monitoring and further mechanistic work to link blood–brain barrier disruption with long‑term neurodegeneration. The results bear on clinical surveillance of former athletes and on trials testing interventions to stabilize the neurovascular unit.