Dale Earnhardt Jr. says he will donate his brain to concussion research after experiencing two concussions and missing two races in 2012.
Dale Earnhardt Jr. says he will donate his brain to concussion research after experiencing two concussions and missing two races in 2012. Mike McCarn AP
Dale Earnhardt Jr. says he will donate his brain to concussion research after experiencing two concussions and missing two races in 2012. Mike McCarn AP