Vin Ferrara’s first brush with concussions was in the seventh grade, when a head injury ended his season in youth football. He endured lesser hits to the head as he ascended football’s ranks, his career culminating as star quarterback for ­Harvard University in the 1990s.

But it was not until years later, as he was finishing medical school, that Ferrara saw sports concussions in a new light. He was watching an old clip of a notorious hit on hockey star Eric Lindros, whose stellar NHL career was undermined by a series of concussions.