By now, it's pretty well-established that playing tackle football can lead to long-term mental problems.
But as part of ongoing research, scientists are increasingly finding that younger players' brains are especially vulnerable to concussions.
The latest piece of evidence for this idea is a new study, published today in the journal Neurology. Researchers from Boston University's CTE Center looked at retired NFL players with memory problems and found that those who started tackle football before the age of 12 had more severe problems than those who picked up the sport later on.
This doesn't necessarily mean that playing football as a child makes everyone more prone to mental problems — but it does suggest there's something especially harmful about childhood head trauma.
There's still a lot of work to be done in this area — and in answering the bigger question of how repetitive brain trauma may lead to the degenerative brain disease Chronic Traumatic Encephalopathy (CTE). But this finding, along with previous ones, backs up the emerging idea that boys shouldn't play tackle football until entering high school, at the earliest.
What the new study found
The research is part of the broader DETECT Study, a Boston University program involving retired NFL players and other athletes that aims to someday figure out a way to diagnose CTE in a living person (right now, the diesease can only be definitively diagnosed during an autopsy).
For this latest paper, the researchers looked at 42 former players culled from the broader study who all experienced memory and thinking problems. Half had begun playing tackle football before the age of 12, and half had started afterward. But the two groups had, on average, played the same total number of years of football, experienced the same number of reported concussions, and were roughly the same age when evaluated.
The researchers found that those players who had picked up the sport earlier on performed significantly worse on cognition and memory tests. The tests measured the players' ability to spot patterns in sets of symbols and remember a list of words they'd learned 15 minutes earlier — both widely used to diagnose mental decline. On the whole, the players who'd started tackle football before the age of 12 performed 20 percent worse than the others.
The researchers note that this data doesn't mean those players will develop debilitating cases of CTE later on. It also doesn't mean that all players who pick up the game at younger ages are more likely to develop mental problems.
But it does indicate that the timing of concussions and other head trauma could be particularly important in the development of these long-term cognitive issues. And the worst time to sustain head trauma on the field, it seems, is as a child.
It's still not certain why, but one possible clue is that concussions and even repeated, more mild brain injuries have been shown inflict permanent damage to the brain's white matter over time. It's theorized that hits to the still-developing brains of children could cause especially high levels of damage.
What we know about football, concussions, and the brain
Over the past decade or so, several prominent former NFL players have committed suicide after suffering from years of emotional and memory problems. When doctors examined their brains afterward, they found evidence of a long-term disease called chronic traumatic encephalopathy, or CTE.
Although the symptoms may appear during a patient’s lifetime, a definitive diagnosis can only be made after death, when doctors have the chance to examine the brain and look for telltale signs of the disease. In postmortem exams, heavy depositions of a protein called tau in the brain are one sign of CTE.
At least 50 retired NFL players have been diagnosed with CTE so far, but hundreds more are probably living with it undiagnosed. Scientists have found it can cause a range of problems — headaches, difficulty concentrating, erectile dysfunction, depression, increased anger and aggression, reduced impulse control, and eventually, severe dementia — which often don't appear until years after a player has retired.
Scientists still don’t really understand how repetitive brain trauma causes CTE. Some believe that damage to the brain's white matter (called diffuse axonal injury) is to blame, while others hypothesize that hits disrupt the blood-brain barrier (the lining that prevents molecules in your bloodstream from entering your brain), potentially causing undetectable long-term damage.
The most disturbing news might be the mounting evidence that mild, routine hits — which present no immediate symptoms and are generally categorized as sub-concussions, rather than concussions — might also lead to CTE. This could be a big problem because a lot of football players (especially offensive and defensive lineman) experience these sorts of hits over and over throughout a game as a matter of routine. If CTE is as common as some scientists believe, the NFL could have an epidemic on its hands.
What the NFL is doing about it
For years, the NFL tried its best to cover up evidence about football and brain trauma. The league's committee on players’ health, released findings that were deeply inconsistent with those of other neurologists, telling players that there was no problem with a concussed player returning to a game and no long-term health issues associated with the injuries.
Then, in 2009 — after Congress grilled NFL commissioner Roger Goodell during hearings — the league abruptly changed course, finally abruptly changed course. Since, it's donated money for concussion and CTE research, offered money for improved helmets, made some rule changes to reduce the number of concussions suffered by players, and put new protocols in place to ensure that concussed players stay away from the game longer, to reduce their risk of second concussion.
Still, lots of people are skeptical that tackle football can ever really be safe. It's difficult to tell if the rule changes have reduced concussions so far, and there's also the possibility that mild, sub-concussive hits can cause CTE over time. If that's the case, it seems that tackle football will inextricably lead to long-term brain problems — especially for players who pick up the sport as children.
Further reading: We lost our son to football and brain disease. This is our story.