Well, certainly I think everybody knows about Muhammad Ali and his Parkinson's disease, which is felt to be as a result of repeated blows to the head. We do know from the boxing studies that there are, as I mentioned, potential long-term effects from repeated blows to the head. This includes anything from memory loss to personality changes to movement disorders, which Parkinson's is part of, and Alzheimer-like symptoms, quite apart from the mental health issues that have been associated with severe head injuries, such as depression, behavioural changes, and those sorts of things.
We know some of that from the boxing literature. Again, as we've said, we don't have the studies for mixed martial arts at this time, but we feel that there may well be similar potential injuries.