As a Social Worker in a nearby hospital, I have dealt directly with patients who have suffered traumatic brain injury, so I am particularly sensitive to the subject.   It is known that those with traumatic brain injury (TBI) may experience a wide range of affects including explosive anger, irritability as well as possible changes in personality, understanding and confusion.  Moreover, it can be subtle and may not be known until much later.  While I have known soldiers with TBI returning from Iraq and Afghanistan, there are those who can get TBI from a car accident, such as one of my current clients, who has memory and processing issues.

In terms of sports, such as skiing, or football, this is purely a voluntary activity which carries the risk of injury and it is well known that helmets do not protect the brain, but rather the skull.  While I did not hear President Obama's comments about football and his likely followup on the issue of brain injury, I assume that he takes a rather paternalistic position on this issue.   While I see the effects of TBI,  I do not believe that we can regulate people's free will to willingly participate in something that may cause them to become injured.