It doesn’t take a concussion for head hits to harm young brains

Most head impacts while playing football do not cause concussions. Yet even lesser impacts take a toll in young athletes, scans of their brains show.

It doesn’t take a concussion for head hits to harm young brains

American football is a rough game, even at the middle-school level. A new study finds that the heads of young players can get hit hundreds of times each season. And those hits can leave their mark on a young player’s brain, researchers now report.

The hits causing changes do not even have to be hard enough to cause a concussion, a type of traumatic brain injury.

Jillian Urban is a biomedical engineer at Wake Forest University in Winston-Salem, N.C. Her team attached devices to the padding inside helmets worn by 195 boys who play football. Most of the kids ranged in age from 10 to 14. Sensors in their helmets recorded changes in the rate and direction of their heads’ movements. These data showed how many times each kid’s head had sustained a hit during play, along with where and how hard each hit had been.

Urban’s group tallied these data over five years. About one in four kids had played football at least two years in a row. And these 47 players together logged a total of more than 41,000 head impacts!

The average number per boy in each season ranged from 296 to 323. Most hits took place during practice. Luckily, few of the head hits were severe enough to cause concussions. Those head traumas can lead to headaches, dizziness, forgetfulness — even unconsciousness.

Urban’s team reported its findings in August’s Journal of Neurosurgery: Pediatrics.

These images show abnormal areas in two football players’ brains after playing two seasons. Changes reflect comparisons with brains of athletes in non-contact sports. Pink highlights areas found after the season with more head hits per practice. Blue shows abnormal areas found in the other season. Green shows areas of overlap from both seasons.M. Kelley et al., Journal of Neurosurgery: Pediatrics, 2021. Copyright American Association of Neurosurgeons.

Looking into the brain

The researchers also imaged the brains of 19 football players before and after each of two back-to-back seasons of play. This magnetic resonance imaging focused on the brain’s white matter.

“I think of [white matter] as communications highways in the brain,” Urban says. It sends signals “from one area of the brain to another.” This white matter contains fibers known as axons. They extend out from cells called neurons. Myelin, a fatty material, covers many of these nerve fibers and gives white matter its color.

Explainer: What is a neuron?

Elizabeth Davenport at the University of Texas Southwestern in Dallas also worked on the new study. This biomedical engineer likens white matter to rubber garden hoses. Think of the axon and information flowing through it as a garden hose carrying water, she says. As with a hose, she explains, “if you break the outer [myelin] layer, the information isn’t going to get where it needs to go as efficiently.”

The researchers also took MRI scans of the brains of 16 young athletes who played non-contact sports, such as swimming, track and tennis. These athletes formed a control group against which the football players were compared.

a team of football players lines up to start a play
Although helmets provide some protection, a new study links even mild, helmeted impacts to changes in the brain.Tetra Images – Erik Isakson/Brand X Pictures.

Urban’s group tallied how many points in the white matter of the football players’ brains differed from what was typical for the control group. “The more points where the white matter was different, the higher their score,” Davenport says. Players with higher scores had, on average, sustained more frequent hits per practice session.

In a separate study, Urban and others looked at the frequency and force of head impacts in soccer. Eight girls, aged 14 to 15, wore mouthpieces with sensors during practices and games. In two seasons, the girls had more frequent head hits during practice. But head impacts during games were generally more forceful.

Graduate student Stewart Pritchard, at Wake Forest, talked about the work at the American Academy of Neurology’s Sports Concussion Conference on July 30.

What do the findings mean?

“Right now, all we know is that the brain is changing,” says Davenport — and not in a good way. That correlation, she says, “tells us that just hitting your head, even without a concussion, can cause changes.”

She and others don’t know what the long-term effects of those white-matter changes might be.

During adolescence, “We know that there are there’s lot of [brain] development going on,” says Ravi Menon. He’s a medical biophysicist at Canada’s Western University in London, Ontario. The brain constantly prunes neurons and connections as it moves toward adulthood, he notes. At the same time, young people are going through puberty, learning new things and forming important social bonds.

Anything that disrupts all of this is “really not good,” he says.

a group of girl rugby players mid-action on the field
Head impacts also happen in girls’ and women’s sports. One 2020 study found changes in brain tissue of college rugby players.creativephoto/iStock/Getty Images Plus.

Menon did not work on the new study. His group has, however, done studies on athletes who get repeated hits to the head. One focused on college women who played rugby, another contact sport. Changes emerged in the white matter of their brains, too. His team’s findings appeared in the July 28, 2020 Neurology.

“We don’t want to scare people,” Menon says, because in most athletes, “the brain seems to recover.” This plasticity, he says, is the brain’s way of rewiring itself. However, he adds, changes are clearly showing up on those MRI scans. And, he adds, “We know it’s damage.”

Will too many hits to the noggin make recovery harder from other problems that may happen years from now? “We basically don’t know,” Menon says. “The benefits of exercise,” he adds, “outweigh all the risks that we know of right now.” But over time and repeated head hits, he says, “contact sports do have some unquantifiable risk.”

“The good news is that the less you hit your head, the fewer changes we see,” Davenport says.

Practice is where most head hits occurred, she points out. And “practice takes up a lot more time than games. So by modifying practice drills,” she says, “we could significantly reduce the number of head impacts.” And that would allow players to still enjoy their favorite sports.

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Racism lurks in many plant and animal names. That’s now changing.

Racist legacies linger in everyday lingo for birds, plants and other organisms. Some scientists now see the chance to change that.

Racism lurks in many plant and animal names. That’s now changing.

With lemon and black feathers, Scott’s oriole flashes about the desert like a flame. But this bird’s name has a violent history that Stephen Hampton can’t forget. Hampton is a birder and a citizen of the Cherokee Nation. He often saw Scott’s orioles when he lived in California. Now that he lives outside the bird’s range, “I’m kind of relieved,” he says.

The bird was named after Winfield Scott, a U.S. military commander in the 1800s. Scott drove Hampton’s ancestors and other Native Americans from their land during a series of forced marches. These marches came to be known as the Trail of Tears. The journey killed more than 4,000 Cherokee and displaced as many as 100,000 people.

“So much of the Trail of Tears is already erased,” Hampton says. “There’s a few historical sites. But you’d have to be an archaeologist to figure out where [they] were.” Linking Scott’s legacy to a bird “is just adding to the erasure” of this violence. 

Scientists are now thinking about renaming the oriole. It’s just one of dozens of species that may be renamed because of racist or other offensive history.

Racist relics exist in both scientific and common names for species. Scientific names used around the world are written in Latin. But common names vary by language and region. They have a smaller reach than scientific names. In theory, that could make them simpler to change. But some common names become formally recognized by scientific societies. That can lend more credibility to names with ugly legacies.

Advocates for change argue that some of these names make science less inclusive. The names may also distract from the organisms themselves. But those advocates aren’t just focused on the negatives. They also see positive opportunities in renaming.

Insect name changes

“We can choose language that reflects our shared values,” says Jessica Ware. She’s an entomologist — someone who studies insects. She works at the American Museum of Natural History in New York City. Ware is also president-elect of the Entomological Society of America, or ESA. Name changes are nothing new, she says. Scientific and common names both shift as scientists learn more about a species. ESA updates its list of English common names for insects each year.

In July, ESA removed the term “gypsy” from its common names for two insects. That’s because many consider this word a slur for Romani people. That left a moth (Lymantria dispar) and an ant (Aphaenogaster araneoides) in need of new common names. ESA is currently inviting suggestions from the public. In the meantime, the insects will go by their scientific names.

The Entomological Society of America is seeking public input on a new common name for the moth Lymantria dispar. In July, the society retired the name “gypsy moth,” which contained a pejorative for Romani people.Heather Broccard-Bell/E+/Getty Images

“This is a moral, necessary and long-overdue change,” says Margareta Matache. She’s a Roma rights activist and scholar at Harvard University in Boston, Mass. It’s a “small yet historic” step, she argues, to correct portrayals where “Roma have been denied humanity or depicted as less than human.”

ESA has also launched the Better Common Names Project. It forbids insect names based on negative stereotypes. The society welcomes public input about which names to change next. So far, more than 80 insensitive names have been identified. Over 100 name ideas for the moth L. dispar have streamed in. It’s a “bottom-up swelling of names” to choose from, Ware says. “Everybody is included.”

Bird by bird

Racist legacies lurk in lingo for many kinds of species. Some scorpions, birds, fishes and flowers are known by the label Hottentot. This is a term of abuse for Indigenous Khoikhoi people in southern Africa. Likewise, the Digger pine tree contains a slur for the Paiute people. This tribe is native to the western United States. Its people were once derisively called diggers by white settlers.

The bird world, in particular, has been reckoning with hurtful legacies. Many bird species identified in the 19th century were named after people. Today, 142 North American bird names are verbal monuments to people. Some names pay tribute to people who participated in genocide, like Winfield Scott. Other names honor people who defended slavery. One example is Bachman’s sparrow. “Blacks and Native Americans would have always been opposed to these names,” Hampton says.

Since 2020, the grassroots campaign Bird Names for Birds have pushed for a solution. Supporters of this effort propose renaming all birds that were named after people. The birds’ new names should describe the species. “It’s not a be-all-end-all solution” to making birding more inclusive, says Robert Driver. But it’s one gesture of “consideration for everyone who’s out there with binoculars.” Driver is an evolutionary biologist at East Carolina University. That’s in Greenville, N.C.

In 2018, Driver proposed renaming a brownish-gray bird called McCown’s longspur. This bird was named after a Confederate general. The American Ornithological Society originally rejected Driver’s idea. But in 2020, the murder of George Floyd sparked nationwide reflection on racism. As a result, some Confederate monuments were removed from public places. Sports teams began rebranding their teams with less offensive names. And the ornithology society changed its bird-naming policies. The society may now remove someone from a bird’s name if they played a role in “reprehensible events.” The McCown’s longspur has since been renamed the thick-billed longspur. 

Driver wants Scott’s oriole to be next. But for now, English bird-name changes have paused. They’re on hold until the society comes up with a new name-changing process. “We are committed to changing these harmful and exclusionary names,” says Mike Webster. He’s president of the society and an ornithologist at Cornell University in Ithaca, N.Y.

Building back better

Removing harmful terms could help species names stand the test of time, Ware says. With thoughtful criteria, scientists and others can craft names built to last. “So it might be uncomfortable now,” Ware says. “But hopefully, that only happens once.”

Let’s learn about bias

As for Hampton, he doesn’t see Scott’s oriole anymore. His new home in Washington State is outside the bird’s range. But he still can’t escape these types of names. Sometimes while birding, he spies Townsend’s solitaire. It’s named after John Kirk Townsend, an American naturalist. Townsend collected Indigenous people’s skulls in the 1830s to measure their size. Those measurements were used to justify bogus ideas about some races being better than others.

But there’s a lot more to these little gray birds than their name’s ugly history. For instance, they love juniper berries. “Every time I see one [of the birds], I’m thinking, ‘That should be juniper solitaire,’” Hampton says. In the same way, Hampton imagines calling the Scott’s oriole the yucca oriole. That would honor the birds’ fondness for foraging on yucca plants. “I can’t wait for those [names] to be changed,” he says.

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