Doctors found evidence of brain damage, called chronic traumatic encephalopathy, that has been observed in retired players who've had many concussions. Unlike those older players, Henry was 26 when he died.
Later in the article, one researcher in the area cautions that no causal link has been established between chronic traumatic encephalopathy (CTE) and concussions from football. Establishing a causal link would probably be difficult because it would involve nailing down the chemistry by which concussions and recovery from concussions would result in the accumulation of Tau proteins involved in CTE.
Still, there are a number of cases of older former football players suffering from CTE. The main question is how Chris Henry's playing professional football might have resulted in early onset CTE.
What makes Henry's case especially ominous is that he played wide receiver rather than one of the "head-knocking positions" in football. At most, wide receivers would only get hit eight to ten times a game and might not get hit at all. play. To the contrary, offensive and defensive linemen can be seen as using their heads on almost every play--every running play anyway. They don't just use their heads in games either. Any kind of scrimmage or full-contact blocking drill would involve head use by linemen. The same with linebackers.
The big physical safeties use their heads as battering rams. Running backs and quarterbacks take a lot of hits to the head as well.
Football's a brutal game.
However, Wide receivers don't have passes thrown to them on most plays and therefore aren't being subject to being tackled on most plays. Likewise, where wide receivers are most susceptible to head injuries is catches over the middle of the field and my understanding is that Chris Henry was not primarily a middle of the field receiver. So, Chris Henry would have been even less likely to suffere concussions than other wide receivers.
As a result, the fact that Henry had early onset brain damage is very disturbing and raises the question of whether the game itself has become dangerous in a systematic way.