Head hits, not just concussions, may lead to CTE
A new study shows that hits to the head that do not cause a concussion can still lead to CTE.

By Joseph Scalise | 5 hours ago

A group of scientists from various U.S. universities have discovered that repeated blows to the head, not just concussions, can lead to the brain disease chronic traumatic encephalopathy (CTE).

This new research -- which shows the risks of younger athletes playing contact sports -- used two methods to reach its findings. The first was a postmortem examination of four teenage brains, and the second was a study of mice that revealed what changes happen to the brain immediately after trauma.

This study sheds new light on brain trauma, and reveals why roughly 20 percent of brains found to have CTE came from people who never had a concussion. It also calls into question current concussion protocols, and could have a wide range of applications for sports players, domestic abuse victims, and members of the military.

"There are going to be policy implications to this," study co-author Lee E. Goldstein, physician and associate professor at Boston University School of Medicine and College of Engineering, told USA Today. "This is concerning, particularly for kids who are not old enough to make other decisions legally on their own -- like to smoke, drink or drive a car. Just like we don't allow kids to do those activities, I think we have a moral obligation to protect them from harm."

The team reports that the only surefire way to limit the risk of CTE is to reduce the number of head impacts a person suffers. While most of the current focus is on concussion and symptomatic recovery, those do not directly address the base problem.

In the past, researchers believed that concussions were the main driver of CTE, a disease that can lead to impulsive behavior, depression, suicidal thoughts, irritability, sleep disorders, and short-term memory loss. However, the four teenage brains analyzed in the study showed that head hits were a much bigger factor.

The team compared the brains to four control subjects that were the same age and who did not have a history of head trauma. None of them showed signs of CTE.

To get a further look at that discrepancy, the scientists turned to mice to see if CTE could result in damaged blood vessels within the brain, which could then trigger brain inflammation and the development of proteins that are believed to play the key role in CTE. The team used aspecial device to give mice precise impacts that led to mild brain trauma. Scans of the rodents after the hits showed immediate changes to the electrical function of their brains.

Both trials could change the way scientists look at CTE. The team plans to continue their research to see what else they can figure out about how head hits and directly connected to the disease.

"We've had an inkling that subconcussive hits the ones that don't [show] neurological signs and symptoms may be associatedwith CTE," addedGoldstein, according to NPR. "We now have solid scientific evidence to say that is so."

The new research is outlined in the journal Brain

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