FILE - In this Sept. 23, 2012, file photo, Washington Redskins quarterback Robert Griffin III hits the turf after being sacked during the first half of an NFL football game against the

 

              FILE - In this Sept. 23, 2012, file photo, Washington Redskins quarterback Robert Griffin III hits the turf after being sacked during the first half of an NFL football game against the
FILE - In this Sept. 23, 2012, file photo, Washington Redskins quarterback Robert Griffin III hits the turf after being sacked during the first half of an NFL football game against the Cincinnati Bengals in Landover, Md. NFL executives want to change the culture of the league _ and all of football _ to reduce head injuries. (AP Photo/Alex Brandon, File)