The NFL just got a little safer. Commissioner Roger Goodell sent out a memo to all 32 clubs on Wednesday stating that players who sustain head injuries should not return to game play if they show certain symptoms, including inability to remember assignments or plays, memory gaps, and persistent dizziness or headaches. Players removed for the rest of a game could not return until a normal neurological examination, neurological testing, and clearance from both a team physician and independent neurological consultant. The previous concussion rule, set in 2007, simply said that players who lost consciousness could not return to the same game. The memo also encouraged players "to be candid with team medical staffs and fully disclose any signs or symptoms that may be associated with a concussion." An Associated Press survey of 160 NFL players found that almost one-fifth had concealed or played down a concussion.