Soccer headers may hurt women’s brains more than men’s

Damage occurs in both sexes but is more extensive in women

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In a head-to-head comparison, soccer balls appeared to damage women’s brains more than men’s.

Henry Huey/Flickr (CC BY-NC 2.0)

Heading soccer balls seems to take a greater toll on women than on men. That’s the conclusion of a new study. It focused on the brains of amateur soccer players.

Head knocks — such as hitting a soccer ball with your head — can really rattle the brain. Female athletes tend to suffer more symptoms than males do after brain injuries, the study’s authors note. But until now, no one had directly compared damage in men and women after heading balls.

Michael Lipton is a brain-imaging expert. He works at the Albert Einstein College of Medicine in New York City. From 2013 to 2016, he was part of a group that recruited 98 soccer players from amateur teams (including college teams). The players estimated how often they had headed a ball in the past year. The researchers then compared men and women who had reported similar numbers of headers.

The median estimate among men was 487 headers. For women, the median was 469 headers. (The median is the middle number when all the player’s counts were put in order from fewest to most.)

The researchers then pored over the brain scans of each player looking for microscopic signs of damage. They used a type of scan known as diffusion tensor imaging. It’s a form of magnetic resonance imaging. This type of MRI scan can highlight changes in the brain’s white matter. Bundles of fibers make up that white matter. These fibers, called axons, carry electrical signals from nerve cells in one part of the brain to those in another. So damage to white matter risks limiting how well the brain works.

The scans turned up more widespread brain damage in the female players, Lipton’s team now reports. In women, eight regions showed potential damage linked to frequent headers. In men, only three regions did. Overall, these white-matter changes affected some five times more of the brain’s volume in women than in men.

The brain changes studied here weren’t big enough to cause symptoms of concussion or other types of brain damage. But repeated blows to the brain can contribute to memory loss, depression and other problems. One concern is CTE, short for chronic traumatic encephalopathy (En-seff-uh-LAH-puh-thee). This disorder can develop in football players, soldiers and others whose brains had suffered repeated head trauma. CTE can lead to confusion, trouble remembering things and emotional outbursts.

Researchers don’t know why women’s brains appear at greater risk. Differences in their heads and necks may play a role. So might genetics and hormones, the authors noted July 31 in Radiology. They add that greater vulnerability that they found in women points to why it is important to study both sexes.

In men’s brains, three regions (blue) showed possible damage linked with heading a soccer ball. Women fared worse, with eight regions (blue) showing signs of header-linked damage. Each sex had one region (red) that showed stronger connections between brain areas after more frequent headers.
Todd Rubin/Albert Einstein College of Medicine

Laura Sanders is the neuroscience writer at Science News. She holds a Ph.D. in molecular biology from the University of Southern California.

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