All I can say is that when I was working on the sports fields in Australia there was an official checklist of questions to ask a player after a knock like that to decide if they are thinking clearly or if they are suffering from a concussion. This included the usual questions like what is their name, the year, whose the prime minster, maybe a little maths. Though it is debatable if footballers could answer some of those questions even when uninjured you are supposed to administer the test to the team off the field to check what their normal level of response would be so you have something to compare it to.