There are diffetent levels of concussions. Mine were mild and I never knew I had one until the massive hesdache the next day. It was then I went to the doctor. Steve Young got a concussion against Utah State and engineered the winning TD drive. On the last play he tried to hurdle a USU player who was down in front of him. As Steve went up, the guy pushed off the ground. Steve landed with one foot on the guy's back, pushed off and made it to the end zone. Later , during an interview he said he couldn't remember the last drive, let alone stepping on that guy. O did have a friend who got hit in a Rugby game. He couldn't remember our names or how to play rugby. After about the third time he asked me what he was supposed to do, I ran to the sideline and told the coach and took the guy out. So, every concussion is different.