There have been a lot of articles in the newspapers about concussions recently. A concussion happens when you hit your head, hard. For instance, if you run into a tree on the playground, or if someone hits you in the head when you’re playing a sport, or if you fall down and hit your head hard on the ground you can get a concussion.
That’s why in many sports, you must wear a helmet. Helmets can often help prevent a concussion.
Sometimes people go unconscious (black out) when they get a concussion but sometimes they don’t. Research shows that people who have just been hit in the head usually don’t know when they have a concussion.