That's an important question. It was asked of me by the Brain Injury Association of Canada. The cause is preventable, mainly because if we had appropriate CSA-approved helmets, we could prevent what we now know are concussions that go on and on as people play a sport—they ski, toboggan, or whatever. They think they may be protected by current helmets on the market, but we now know those helmets could be as useful as wearing a toque for the amount of protection they give.
I know we've seen it in the case of Sidney Crosby when we've looked at hockey. Everyone used to think it was machismo not to wear a helmet, and we now know that this is a preventable injury. We know acquired brain injury has something to do with Alzheimer's. I do know that it is one of the etiological factors in epileptic seizures.