Scientists have already shown that female soccer players are at a greater risk of concussion than male players. A new study indicates that the problem may encompass lesser injuries, as well — specifically, the “sub-concussive injuries” caused by soccer’s signature move, the header.
The new study, published in the journal Radiology, examined the “white matter” in the brains of amateur soccer players who frequently headed the ball. It used MRI imaging to compare the brains of 49 men and 49 women, each of whom had an opposite-sex counterpart with similar characteristics such as age and frequency of heading.
The lead author, a neuroscientist and neuroradiologist at the Albert Einstein College of Medicine in New York, compared the brain’s “white matter” to the fiber optic cables used to network computers. Similar to fiber optic cable, white matter is made up of thread-like axon fibers connecting the neurons to one another. It is encased in a protective covering called myelin.
Heading the ball doesn’t cause any immediate problems for the player, but it does appear to disorganize the white matter. Previous research indicates that this disorganization is associated with poorer cognitive function, including attention and memory issues. Therefore, the minor but repeated impact of heading the ball could potentially cause longer-term problems.
According to the lead author, scientists are looking to define what happens to people who suffer mild head traumas but experience no symptoms of injury. This could give insight into diseases like chronic traumatic encephalopathy (CTE), which appears to be caused by serial concussions. It could also stave off problems if it is discovered that very light head traumas can cause cumulative injuries.
“The most important finding here,” says the lead author, “is that we see that in women’s brains, actually looking at brain tissue, there seems to be a greater sensitivity to repetitive, very low-level injury relative to men.”
While this study is small, it is the first to contribute concrete facts on the question of whether women’s brains are essentially more sensitive than those of men. Women tend to report concussion symptoms more often than men do, but this could have been due to a greater willingness to admit injury.
Should this study prompt women to stop heading the ball — or stop playing soccer altogether? It’s too early for that, says the study’s lead author. More research needs to be done, and there are many brain-related benefits to be had by getting and staying physically active. For now, “[r]ather than ban heading altogether-which probably isn’t realistic-we’d like to get a better handle on how many headers will get players into trouble. What is important about this study is that men and women may need to be looked at differently.”