Former Kansas City Chiefs players and Army leaders say a change in culture about the risks of concussions is possible but must start at the top levels in sports and the military.
The comments came during a forum Wednesday at Fort Leavenworth on traumatic brain injuries.
Pro Football Hall of Fame linebacker Willie Lanier said he learned the lessons early on.
Lanier, who played from 1967 through 1977, serves on an NFL player safety panel studying ways to make the game safer.
Lanier suffered numerous concussions in rookie season including one that didn't manifest until a week later. Lanier says he changed his playing technique as a result.
The military has been looking at the impact of traumatic brain injuries as soldiers return from combat.