I agree that high level cognitive activity should be moderated and self discipline is required.

The example I gave happened in 2005. I had seven more similar falls after that and I recovered within a week each time with adequate rest. Except for this last one where I overdid-it. And I had many falls before that. So the conclusion I am making is based on many head injuries, unfortunately.

One of the reasons I brought up overdoing-it is because it is so easy to do. Most people don't realize the difference between low-level and high-level cognitive activity. Even if they do understand, people have responsibilities and obligations that are hard to get out of. Or teens may be too stubborn to admit they might have injured their head. So preventing PCS requires more awareness.