Robert Griffin III attended a rookie seminar Monday morning at Redskins Park, according to backup quarterback Kirk Cousins.Griffin sustained a concussion in the third quarter of Sundays 24-17 loss to the Falcons and did not return to the game.He seems fine, Cousins said. He seems in good spirits. He appears to be doing well.Asked if he believes Griffin will be ready to play next week against the Vikings, Cousins shrugged.I dont know, he said. I havent been told anything. It really wouldnt change my approach if I find out Sunday morning or I find out right after Im done talking to you. So well see what happens, but obviously I hope he gets back quickly and is healthy.Griffin was not permitted to speak to reporters after Sunday's loss per NFL rules. His next media availability is following practice on Wednesday, though it's possible Coach Mike Shanahan will provide an update on Griffin's status at 3 p.m. Monday.